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Zhou Y, Gong X, You Y. Prediction of high-intensity focused ultrasound (HIFU)-induced lesion size using the echo amplitude from the focus in tissue. Phys Eng Sci Med 2024:10.1007/s13246-024-01449-2. [PMID: 38822970 DOI: 10.1007/s13246-024-01449-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 05/21/2024] [Indexed: 06/03/2024]
Abstract
In the realm of high-intensity focused ultrasound (HIFU) therapy, the precise prediction of lesion size during treatment planning remains a challenge, primarily due to the difficulty in quantitatively assessing energy deposition at the target site and the acoustic properties of the tissue through which the ultrasound wave propagates. This study investigates the hypothesis that the echo amplitude originating from the focus is indicative of acoustic attenuation and is directly related to the resultant lesion size. Echoes from multi-layered tissues, specifically porcine tenderloin and bovine livers, with varying fat thickness from 0 mm to 35 mm were collected using a focused ultrasound (FUS) transducer operated at a low power output and short duration. Subsequent to HIFU treatment under clinical conditions, the resulting lesion areas in the ex vivo tissues were meticulously quantified. A novel treatment strategy that prioritizes treatment spots based on descending echo amplitudes was proposed and compared with the conventional raster scan approach. Our findings reveal a consistent trend of decreasing echo amplitudes and HIFU-induced lesion areas with the increasing fat thickness. For porcine tenderloin, the values decreased from 2541.7 ± 641.9 mV and 94.4 ± 17.9 mm2 to 385(342.5) mV and 24.9 ± 18.7 mm2, and for bovine liver, from 1406(1202.5) mV and 94.4 ± 17.9 mm2 to 502.1 ± 225.7 mV and 9.4 ± 6.3 mm2, respectively, as the fat thickness increases from 0 mm to 35 mm. Significant correlations were identified between preoperative echo amplitudes and the HIFU-induced lesion areas (R = 0.833 and 0.784 for the porcine tenderloin and bovine liver, respectively). These correlations underscore the potential for an accurate and dependable prediction of treatment outcomes. Employing the proposed treatment strategy, the ex vivo experiment yielded larger lesion areas in bovine liver at a penetration depth of 8 cm compared to the conventional approach (58.84 ± 17.16 mm2 vs. 44.28 ± 15.37 mm2, p < 0.05). The preoperative echo amplitude from the FUS transducer is shown to be a reflective measure of acoustic attenuation within the wave propagation window and is closely correlated with the induced lesion areas. The proposed treatment strategy demonstrated enhanced efficiency in ex vivo settings, affirming the feasibility and accuracy of predicting HIFU-induced lesion size based on echo amplitude.
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Affiliation(s)
- Yufeng Zhou
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, 1 Medical College Road, Chongqing, 400016, China.
- Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China.
- Key Laboratory for Quality Evaluation of Ultrasonic Surgical Equipment, National Medical Products Administration (NMPA), Donghu New Technology Development Zone, 507 Gaoxin Ave, Wuhan, 430075, Hubei, China.
| | - Xiaobo Gong
- National Engineering Research Center of Ultrasound Medicine, Chongqing, 401120, China
| | - Yaqin You
- National Engineering Research Center of Ultrasound Medicine, Chongqing, 401120, China
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Miao K, Basterrechea KF, Hernandez SL, Ahmed OS, Patel MV, Bader KB. Development of Convolutional Neural Network to Segment Ultrasound Images of Histotripsy Ablation. IEEE Trans Biomed Eng 2024; 71:1789-1797. [PMID: 38198256 DOI: 10.1109/tbme.2024.3352538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
OBJECTIVE Histotripsy is a focused ultrasound therapy that ablates tissue via the action of bubble clouds. It is under investigation to treat a number of ailments, including renal tumors. Ultrasound imaging is used to monitor histotripsy, though there remains a lack of definitive imaging metrics to confirm successful treatment outcomes. In this study, a convolutional neural network (CNN) was developed to segment ablation on ultrasound images. METHODS A transfer learning approach was used to replace classification layers of the residual network ResNet-18. Inputs to the classification layers were based on ultrasound images of ablated red blood cell phantoms. Digital photographs served as the ground truth. The efficacy of the CNN was compared to subtraction imaging, and manual segmentation of images by two board-certified radiologists. RESULTS The CNN had a similar performance to manual segmentation, though was improved relative to segmentation with subtraction imaging. Predictions of the network improved over the course of treatment, with the Dice similarity coefficient less than 20% for fewer than 500 applied pulses, but 85% for more than 750 applied pulses. The network was also applied to ultrasound images of ex vivo kidney exposed to histotripsy, which indicated a morphological shift in the treatment profile relative to the phantoms. These findings were consistent with histology that confirmed ablation of the targeted tissue. CONCLUSION Overall, the CNN showed promise as a rapid means to assess outcomes of histotripsy and automate treatment. SIGNIFICANCE Data collected in this study indicate integration of CNN image segmentation to gauge outcomes for histotripsy ablation holds promise for automating treatment procedures.
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Mustafa W, Hall S, Huynh L, Mannasse R, Luleburgaz S, Vlaisavljevich E, Yuksel Durmaz Y. Investigation of Optimum Production Conditions and the Stability of β-Cyclodextrin-Perfluorocarbon Nanocone Clusters for Histotripsy Applications. Mol Pharm 2024; 21:2383-2393. [PMID: 38551360 DOI: 10.1021/acs.molpharmaceut.3c01178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
Nanocone clusters (NCCs) have been developed as clusters with inclusion complexes of FDA-approved β-cyclodextrin (βCD) and perfluorocarbons (PFC) (i.e., perfluoropentane (PFP) and perfluorohexane (PFH)) and have shown promise in nanoparticle-mediated histotripsy (NMH) applications owing to their lowered cavitation threshold, ease of production, and fluorocarbon quantification. However, there is still a lack of information on the best conditions of the synthesis of NCCs as a product that can have a maximum determinable fluorocarbon content and maintain the stability of the NCC during synthesis and when used as histotripsy agents or exposed to physiological conditions. These concerns about the stability of the clusters and the best possible formulation are investigated in the current work. The cluster formation potential was tested taking into consideration the nature of both PFCs and βCD by employing different synthesis conditions in terms of solution and environmental parameters such as concentration of solvent, stoichiometry between βCD and PFCs, temperature, pH, solvent type, etc. The best route of synthesis was then translated into various batch sizes and investigated in terms of the PFC loading and yield. These studies revealed that preparing NCCs in double-distilled water in an ice bath at the optimized solution concentration gave the highest yields and optimal PFC loading, as determined from gas chromatography. Furthermore, the stability of the clusters with different stoichiometries was scrutinized in varying concentrations, mechanical disruption times, pH levels, and temperature conditions, showing effects on each cluster's particle size in dynamic light scattering, visualized in transmission electron microscopy, and cavitation behavior in agarose gel tissue phantoms. These studies revealed stable clusters for all formulations, with PFH-containing NCCs emerging to be the most stable in terms of their cluster size and bubble formation potential in histotripsy. Finally, the shelf life of these clusters was investigated using DLS, which revealed a stable cluster. In conclusion, NCCs have shown high stability in terms of both synthesis, which can be replicated in gram-level production, and the cluster itself, which can be exposed to harsher conditions and still form stable bubbles in histotripsy.
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Affiliation(s)
- Waleed Mustafa
- Department of Biomedical Engineering, Istanbul Medipol University, Istanbul 34810, Turkey
| | - Sarah Hall
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Laura Huynh
- Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Rachel Mannasse
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Serter Luleburgaz
- Department of Chemistry, Istanbul Technical University, Istanbul 34469, Turkey
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Yasemin Yuksel Durmaz
- Department of Biomedical Engineering, Istanbul Medipol University, Istanbul 34810, Turkey
- Research Institute of Health Science and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Turkey
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Zhu H, Zeng Y, Cai X. Passive Acoustic Mapping for Convex Arrays With the Helical Wave Spectrum Method. IEEE TRANSACTIONS ON MEDICAL IMAGING 2024; 43:1923-1933. [PMID: 38198274 DOI: 10.1109/tmi.2024.3352283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Passive acoustic mapping (PAM) has emerged as a valuable imaging modality for monitoring the cavitation activity in focused ultrasound therapies. When it comes to imaging in the human abdomen, convex arrays are preferred due to their large acoustic window. However, existing PAM methods for convex arrays rely on the computationally expensive delay-and-sum (DAS) operation limiting the image reconstruction speed when the field-of-view (FOV) is large. In this work, we propose an efficient and frequency-selective PAM method for convex arrays. This method is based on projecting the helical wave spectrum (HWS) between cylindrical surfaces in the imaging field. Both the in silico and in vitro experiments showed that the HWS method has comparable image quality and similar acoustic cavitation source localization accuracy as the DAS-based methods. Compared to the frequency-domain and time-domain DAS methods, the time-complexity of the HWS method is reduced by one order and two orders of magnitude, respectively. A parallel implementation of the HWS method realized millisecond-level image reconstruction speed. We also show that the HWS method is inherently capable of mapping microbubble (MB) cavitation activity of different status, i.e., no cavitation, stable cavitation, or inertial cavitation. After compensating for the lens effects of the convex array, we further combined PAM formed by the HWS method and B-mode imaging as a real-time dual-mode imaging approach to map the anatomical location where MBs cavitate in a liver phantom experiment. This method may find use in applications where convex arrays are required for cavitation activity monitoring in real time.
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Kutlu AZ, Minesinger GM, Laeseke PF, Speidel M, Wagner MG. A target containing phantom for accuracy assessment of cone-beam CT-guided histotripsy. J Appl Clin Med Phys 2024; 25:e14329. [PMID: 38497567 PMCID: PMC11087156 DOI: 10.1002/acm2.14329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 02/13/2024] [Accepted: 02/29/2024] [Indexed: 03/19/2024] Open
Abstract
PURPOSE Histotripsy is a nonionizing, noninvasive, and nonthermal focal tumor therapy. Cone-beam computed tomography (CBCT) guidance was developed for targeting tumors not visible on ultrasound. This approach assumes cavitation is formed at the geometrical focal point of the therapy transducer. In practice, the exact location might vary slightly between transducers. In this study, we present a phantom with an embedded target to evaluate CBCT-guided histotripsy accuracy and assess the completeness of treatments. METHODS Spherical (2.8 cm) targets with alternating layers of agar and radiopaque barium were embedded in larger phantoms with similar layers. The layer geometry was designed so that targets were visible on pre-treatment CBCT scans. The actual histotripsy treatment zone was visualized via the mixing of adjacent barium and agar layers in post-treatment CBCT images. CBCT-guided histotripsy treatments of the targets were performed in six phantoms. Offsets between planned and actual treatment zones were measured and used for calibration refinement. To measure targeting accuracy after calibration refinement, six additional phantoms were treated. In a separate investigation, two groups (N = 3) of phantoms were treated to assess visualization of incomplete treatments ("undertreatment" group: 2 cm treatment within 2.8 cm tumor, "mistarget" group: 2.8 cm treatment intentionally shifted laterally). Treatment zones were segmented (3D Slicer 5.0.3), and the centroid distance between the prescribed target and actual treatment zones was quantified. RESULTS In the calibration refinement group, a 2 mm offset in the direction of ultrasound propagation (Z) was measured. After calibration refinement, the centroid-to-centroid distance between prescribed and actual treatment volumes was 0.5 ± 0.2 mm. Average difference between the prescribed and measured treatment sizes in the incomplete treatment groups was 0.5 ± 0.7 mm. In the mistarget group, the distance between prescribed and measured shifts was 0.2 ± 0.1 mm. CONCLUSION The proposed prototype phantom allowed for accurate measurement of treatment size and location, and the CBCT visible target provided a simple way to detect misalignments for preliminary quality assurance of CBCT-guided histotripsy.
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Affiliation(s)
- Ayca Z. Kutlu
- Department of RadiologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Grace M. Minesinger
- Department of Medical PhysicsUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Paul F. Laeseke
- Department of RadiologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Michael Speidel
- Department of Medical PhysicsUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
- Department of MedicineUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Martin G. Wagner
- Department of RadiologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
- Department of Medical PhysicsUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
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Siedel S, Gu T. Toward a complete understanding of quasi-static bubble growth and departure. Proc Natl Acad Sci U S A 2024; 121:e2317202121. [PMID: 38602913 PMCID: PMC11032486 DOI: 10.1073/pnas.2317202121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 02/29/2024] [Indexed: 04/13/2024] Open
Abstract
The distortion by gravity of a quasi-static bubble attached on an upward facing surface in a quiescent liquid is investigated. The contact angle evolution during the growth of such a bubble is studied, and the consequences on the motion of the contact line between the solid and the interface are discussed. From the initial case of a bubble attached to the rim of a nucleation site, the contact line can move inside the cavity for a highly wetting fluid, causing premature departure. For a higher wettability, the contact can either remain attached to the rim of the cavity or spread out of the cavity, depending on the cavity size and geometry. For the latter case, the bubble growth is investigated taking into account a contact angle hysteresis. Finally, a comprehensive map detailing various geometrical characteristics of bubbles is presented, ranging over several orders of magnitude of Bond numbers and normalized volumes. The map aims at being used as a tool for investigating bubble growth in a similar situation.
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Affiliation(s)
- Samuel Siedel
- EPM Group, SIMaP Laboratory, CNRS, Grenoble-INP, University Grenoble Alpes, Grenoble, France38402
| | - Tianle Gu
- EPM Group, SIMaP Laboratory, CNRS, Grenoble-INP, University Grenoble Alpes, Grenoble, France38402
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Iqbal MF, Shafique MA, Abdur Raqib M, Fadlalla Ahmad TK, Haseeb A, M. A. Mhjoob A, Raja A. Histotripsy: an innovative approach for minimally invasive tumour and disease treatment. Ann Med Surg (Lond) 2024; 86:2081-2087. [PMID: 38576932 PMCID: PMC10990312 DOI: 10.1097/ms9.0000000000001897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 02/26/2024] [Indexed: 04/06/2024] Open
Abstract
Histotripsy is a noninvasive medical technique that uses high-intensity focused ultrasound (HIFU) to treat liver tumours. The two main histotripsy methods are boiling histotripsy and cavitation cloud histotripsy. Boiling histotripsy uses prolonged ultrasound pulses to create small boiling bubbles in the tissue, which leads to the breakdown of the tissue into smaller subcellular fragments. Cavitation cloud histotripsy uses the ultrasonic cavitation effect to disintegrate target tissue into precisely defined liquefied lesions. Both methods show similar treatment effectiveness; however, boiling histotripsy ensures treatment stability by producing a stable boiling bubble with each pulse. The therapeutic effect is ascribed to mechanical damage at the subcellular level rather than thermal damage. This article discusses the mechanisms, treatment parameters, and potential of histotripsy as a minimally invasive procedure that provides precise and controlled subcellular damage.
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Affiliation(s)
| | | | | | | | - Abdul Haseeb
- Department of Medicine, Jinnah Sindh Medical University
| | | | - Adarsh Raja
- Department of Medicine, Shaheed Mohtarma Benazir Bhutto Medical College, Karachi, Pakistan
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Landry TG, Brown JA. Ultrasound imaging guided precision histotripsy: Effects of pulse settings on ablation properties in rat brain. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:2860-2874. [PMID: 38682916 DOI: 10.1121/10.0025832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/10/2024] [Indexed: 05/01/2024]
Abstract
A high-frequency 6 MHz miniature handheld histotripsy device with an endoscopic form factor and co-registered high-resolution ultrasound imaging was developed. This device could allow precision histotripsy ablation during minimally invasive brain tumor surgeries with real-time image guidance. This study characterized the outcome of acute histotripsy in the normal in vivo rat brain using the device with a range of histotripsy pulse settings, including number of cycles, pulse repetition frequency, and pressure, as well as other experimental factors. The stability and shape of the bubble cloud were measured during ablations, as well as the post-histotripsy ablation shape in ultrasound B-mode and histology. The results were compared between histological images and the ultrasound imaging data to determine how well ultrasound data reflected observable damage in histology. The results indicated that while pulse settings can have some influence on ablation shape, sample-to-sample variation had a larger influence on ablation shape. This suggests that real-time ablation monitoring is essential for accurate knowledge of outcomes. Ultrasound imaging provided an accurate real-time indication of ablation shape both during ablation and post-ablation.
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Affiliation(s)
- Thomas G Landry
- School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
- Division of Surgery, Nova Scotia Health, Halifax, Nova Scotia, Canada
| | - Jeremy A Brown
- School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
- Division of Surgery, Nova Scotia Health, Halifax, Nova Scotia, Canada
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Lin X, Chen S, Su Y, Wu Y, Huang L, Ye Q, Song J. Ultrasound Activated Nanobowls with Deep Penetration for Enhancing Sonodynamic Therapy of Orthotopic Liver Cancer. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306301. [PMID: 38247202 PMCID: PMC10987158 DOI: 10.1002/advs.202306301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 12/07/2023] [Indexed: 01/23/2024]
Abstract
Owing to the high penetration ability and the safety of ultrasound (US) of sonodynamic therapy (SDT), it has gained significant attention in tumor treatment. However, its therapeutic efficiency depends on the performance of the sonosensitizers. The hypoxic microenvironment and abnormal stromal matrix restrict the full potential of sonosensitizers. In this study, a US-activated bowl-shaped nanobomb (APBN) is designed as a novel sonosensitizer to enhance the SDT effect through various means. This enhancement strategy combines three major characteristics: relieving tumor hypoxia, amplifying bubble cavitation damage, and US-movement-enhanced permeation. The unique bowl-shaped structure of APBN provides more favorable attachment sites for the generated oxygen gas bubbles. Thus, when catalase-like APBN catalyzes endogenous hydrogen peroxide to produce oxygen, bubbles accumulate at the groove, preventing the dissipation of oxygen and increasing the number of cavitation nuclei to improve the acoustic cavitation effect. This approach differs from traditional SDT strategies because it couples the sonodynamic effect with reactive oxygen species generation and bubble cavitation damage rather than a single action. Additionally, the asymmetric bowl-shaped structure generates a driving force under the US field, improving the distribution of sonosensitizers in the tumors. Using US and photoacoustic imaging for dual localization, these sonosensitizers can improve the accuracy of orthotopic liver tumor treatment, which presents a promising avenue for the treatment of deep tumors.
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Affiliation(s)
- Xiahui Lin
- School of Medical ImagingFujian Medical UniversityFuzhouFujian350122P. R. China
| | - Shan Chen
- College of Geography and OceanMinjiang UniversityFuzhou350108P. R. China
| | - Yina Su
- School of Medical ImagingFujian Medical UniversityFuzhouFujian350122P. R. China
| | - Ying Wu
- College of ChemistryBeijing University of Chemical TechnologyBeijing10010P. R. China
| | - Linjie Huang
- School of Medical ImagingFujian Medical UniversityFuzhouFujian350122P. R. China
| | - Qin Ye
- Department of UltrasoundUnion HospitalFujian Medical UniversityFujian Institute of Ultrasonic MedicineFuzhou350108P. R. China
| | - Jibin Song
- College of ChemistryBeijing University of Chemical TechnologyBeijing10010P. R. China
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Verma Y, Perera Molligoda Arachchige AS. Revolutionizing brain interventions: the multifaceted potential of histotripsy. Neurosurg Rev 2024; 47:124. [PMID: 38509320 DOI: 10.1007/s10143-024-02353-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/26/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024]
Abstract
Histotripsy, a non-thermal ultrasound technique, holds significant promise in various applications within the realm of brain interventions. While its use for treating brain tumors is somewhat limited, focused ultrasound technology has been extensively investigated for a wide range of purposes within the brain, including disrupting the blood-brain barrier, supporting immunotherapy, addressing conditions like essential tremor, Parkinson's disease, Alzheimer's disease, epilepsy, and neuropathic pain. Research findings indicate that histotripsy can reduce tumor cells with fewer pulses, minimizing the risk of bleeding and cellular injury. The use of MRI sequences such as T2 and T2* enhances the evaluation of the effects of histotripsy treatment, facilitating non-invasive assessment of treated areas. Furthermore, histotripsy displays promise in creating precise brain lesions with minimal edema and inflammation, particularly in porcine models, suggesting considerable progress in the treatment of brain lesions. Moreover, studies confirm its feasibility, safety, and effectiveness in treating intracerebral hemorrhage by safely liquefying clots without causing significant harm to surrounding brain tissue., opening exciting possibilities for clinical applications. The development of transcranial MR-guided focused ultrasound systems based on histotripsy represents a significant breakthrough in overcoming the limitations associated with thermal ablation techniques. Histotripsy's ability to efficiently liquefy clots, minimize skull heating, and target shallow lesions near the skull establishes it as a promising alternative for various brain treatments. In conclusion, histotripsy offers diverse potential in the field of brain interventions, encompassing applications ranging from tumor treatment to the management of intracerebral hemorrhage. While challenges such as accurate monitoring and differentiation of treatment effects persist, ongoing research efforts and technological advancements continue to expand the role of histotripsy in both neurology and neurosurgery.
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Affiliation(s)
- Yash Verma
- Norfolk and Norwich University Hospital, Norwich, UK
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Gong L, Wright AR, Hynynen K, Goertz DE. Inducing cavitation within hollow cylindrical radially polarized transducers for intravascular applications. ULTRASONICS 2024; 138:107223. [PMID: 38553135 DOI: 10.1016/j.ultras.2023.107223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/31/2023] [Accepted: 12/12/2023] [Indexed: 04/02/2024]
Abstract
Thrombotic occlusions of large blood vessels are increasingly treated with catheter based mechanical approaches, one of the most prominent being to employ aspiration to extract clots through a hollow catheter lumen. A central technical challenge for aspiration catheters is to achieve sufficient suction force to overcome the resistance of clot material entering into the distal tip. In this study, we examine the feasibility of inducing cavitation within hollow cylindrical transducers with a view to ultimately using them to degrade the mechanical integrity of thrombus within the tip of an aspiration catheter. Hollow cylindrical radially polarized PZT transducers with 3.3/2.5 mm outer/inner diameters were assessed. Finite element simulations and hydrophone experiments were used to investigate the pressure field distribution as a function of element length and resonant mode (thickness, length). Operating in thickness mode (∼5 MHz) was found to be associated with the highest internal pressures, estimated to exceed 23 MPa. Cavitation was demonstrated to be achievable within the transducer under degassed water (10 %) conditions using hydrophone detection and high-frequency ultrasound imaging (40 MHz). Cavitation clouds occupied a substantial portion of the transducer lumen, in a manner that was dependent on the pulsing scheme employed (10 and 100 μs pulse lengths; 1.1, 11, and 110 ms pulse intervals). Collectively the results support the feasibility of achieving cavitation within a transducer compatible with mounting in the tip of an aspiration format catheter.
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Affiliation(s)
- Li Gong
- Department of Medical Biophysics, University of Toronto, Canada; Physical Sciences Platform, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada.
| | - Alex R Wright
- Physical Sciences Platform, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada
| | - Kullervo Hynynen
- Department of Medical Biophysics, University of Toronto, Canada; Physical Sciences Platform, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - David E Goertz
- Department of Medical Biophysics, University of Toronto, Canada; Physical Sciences Platform, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada
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Simon A, Edsall C, Maxwell A, Vlaisavljevich E. Effects of pulse repetition frequency on bubble cloud characteristics and ablation in single-cycle histotripsy. Phys Med Biol 2024; 69:025018. [PMID: 38041873 DOI: 10.1088/1361-6560/ad11a1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 12/01/2023] [Indexed: 12/04/2023]
Abstract
Objective. Histotripsy is a cavitation-based ultrasound ablation method in development for multiple clinical applications. This work investigates the effects of pulse repetition frequency (PRF) on bubble cloud characteristics and ablative capabilities for histotripsy using single-cycle pulsing methods.Approach.Bubble clouds produced by a 500 kHz histotripsy system at PRFs from 0.1 to 1000 Hz were visualized using high-speed optical imaging in 1% agarose tissue phantoms at peak negative pressures,p-, of 2-36 MPa.Main results.Results showed a decrease in the cavitation cloud threshold with increasing PRF, ranging from 26.7 ± 0.5 MPa at 0.1 Hz to 15.0 ± 1.9 MPa at 1000 Hz. Bubble cloud analysis showed cavitation clouds generated at low PRFs (0.1-1 Hz) were characterized by consistently dense bubble clouds (41.7 ± 2.8 bubbles mm-2at 0.1 Hz), that closely matched regions of the focus above the histotripsy intrinsic threshold. Bubble clouds formed at higher PRFs measured lower cloud densities (23.1 ± 4.0 bubbles mm-2at 1000 Hz), with the lowest density measured for 10 Hz (8.8 ± 4.1 bubbles mm-2). Furthermore, higher PRFs showed increased pulse-to-pulse correlation, characteristic of cavitation memory effects; however, bubble clouds still filled the entire volume of the focus due to their initial density and enhanced bubble expansion from the restimulation of residual nuclei at the higher PRFs. Histotripsy ablation assessed through lesion analysis in red blood cell (RBC) phantoms showed higher PRFs generated lesions with lower adherence to the initial focal region compared to low PRF ablations; however, no trend of decreasing ablation efficiency with PRF was observed, with similar efficiencies observed for all the PRFs tested in this study.Significance.Notably, this result is different than what has previously been shown for shock-scattering histotripsy, which has shown decreased ablation efficiencies at higher PRFs. Overall, this study demonstrates the essential effects of PRF on single-cycle histotripsy procedures that should be considered to help guide future histotripsy pulsing strategies.
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Affiliation(s)
- Alex Simon
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States of America
| | - Connor Edsall
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States of America
| | - Adam Maxwell
- Department of Urology, University of Washington, Seattle, WA, United States of America
| | - Eli Vlaisavljevich
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States of America
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Thim EA, Kitelinger LE, Rivera-Escalera F, Mathew AS, Elliott MR, Bullock TNJ, Price RJ. Focused ultrasound ablation of melanoma with boiling histotripsy yields abscopal tumor control and antigen-dependent dendritic cell activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.02.552844. [PMID: 37732205 PMCID: PMC10508728 DOI: 10.1101/2023.09.02.552844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Background Boiling histotripsy (BH), a mechanical focused ultrasound ablation strategy, can elicit intriguing signatures of anti-tumor immunity. However, the influence of BH on dendritic cell function is unknown, compromising our ability to optimally combine BH with immunotherapies to control metastatic disease. Methods BH was applied using a sparse scan (1 mm spacing between sonications) protocol to B16F10-ZsGreen melanoma in bilateral and unilateral settings. Ipsilateral and contralateral tumor growth was measured. Flow cytometry was used to track ZsGreen antigen and assess how BH drives dendritic cell behavior. Results BH monotherapy elicited ipsilateral and abscopal tumor control in this highly aggressive model. Tumor antigen presence in immune cells in the tumor-draining lymph nodes (TDLNs) was ~3-fold greater at 24h after BH, but this abated by 96h. B cells, macrophages, monocytes, granulocytes, and both conventional dendritic cell subsets (i.e. cDC1s and cDC2s) acquired markedly more antigen with BH. BH drove activation of both cDC subsets, with activation being dependent upon tumor antigen acquisition. Our data also suggest that BH-liberated tumor antigen is complexed with damage-associated molecular patterns (DAMPs) and that cDCs do not traffic to the TDLN with antigen. Rather, they acquire antigen as it flows through afferent lymph vessels into the TDLN. Conclusion When applied with a sparse scan protocol, BH monotherapy elicits abscopal melanoma control and shapes dendritic cell function through several previously unappreciated mechanisms. These results offer new insight into how to best combine BH with immunotherapies for the treatment of metastatic melanoma.
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Affiliation(s)
- Eric A. Thim
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908
| | | | - Fátima Rivera-Escalera
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA 22908
| | - Alexander S. Mathew
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908
| | - Michael R. Elliott
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA 22908
| | | | - Richard J. Price
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908
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Shen Y, Zhang Y, Jiang Y, Cheng H, Wang B, Wang H. Membrane processes enhanced by various forms of physical energy: A systematic review on mechanisms, implementation, application and energy efficiency. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167268. [PMID: 37748609 DOI: 10.1016/j.scitotenv.2023.167268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/05/2023] [Accepted: 09/20/2023] [Indexed: 09/27/2023]
Abstract
Membrane technologies in water and wastewater treatment have been eagerly pursued over the past decades, yet membrane fouling remains the major bottleneck to overcome. Membrane fouling control methods which couple membrane processes with online in situ application of external physical energy input (EPEI) are getting closer and closer to reality, thanks to recent advances in novel materials and energy deliverance methods. In this review, we summarized recent studies on membrane fouling control techniques that depend on (i) electric field, (ii) acoustic field, (iii) magnetic field, and (iv) photo-irradiation (mostly ultraviolet or visible light). Mechanisms of each energy input were first reported, which defines the applicability of these methods to certain wastewater matrices. Then, means of implementation were discussed to evaluate the compatibility of these fouling control methods with established membrane techniques. After that, preferred applications of each energy input to different foulant types and membrane processes in the experiment reports were summarized, along with a discussion on the trends and knowledge gaps of such fouling control research. Next, specific energy consumption in membrane fouling control and flux enhancement was estimated and compared, based on the experimental results reported in the literature. Lastly, strength and weakness of these methods and future perspectives were presented as open questions.
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Affiliation(s)
- Yuxiang Shen
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yichong Zhang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yulian Jiang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Haibo Cheng
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Banglong Wang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Hongyu Wang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
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15
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Biasiori-Poulanges L, Lukić B, Supponen O. Cavitation cloud formation and surface damage of a model stone in a high-intensity focused ultrasound field. ULTRASONICS SONOCHEMISTRY 2024; 102:106738. [PMID: 38150955 PMCID: PMC10765487 DOI: 10.1016/j.ultsonch.2023.106738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 12/29/2023]
Abstract
This work investigates the fundamental role of cavitation bubble clouds in stone comminution by focused ultrasound. The fragmentation of stones by ultrasound has applications in medical lithotripsy for the comminution of kidney stones or gall stones, where their fragmentation is believed to result from the high acoustic wave energy as well as the formation of cavitation. Cavitation is known to contribute to erosion and to cause damage away from the target, yet the exact contribution and mechanisms of cavitation remain currently unclear. Based on in situ experimental observations, post-exposure microtomography and acoustic simulations, the present work sheds light on the fundamental role of cavitation bubbles in the stone surface fragmentation by correlating the detected damage to the observed bubble activity. Our results show that not all clouds erode the stone, but only those located in preferential nucleation sites whose locations are herein examined. Furthermore, quantitative characterizations of the bubble clouds and their trajectories within the ultrasonic field are discussed. These include experiments with and without the presence of a model stone in the acoustic path length. Finally, the optimal stone-to-source distance maximizing the cavitation-induced surface damage area has been determined. Assuming the pressure magnitude within the focal region to exceed the cavitation pressure threshold, this location does not correspond to the acoustic focus, where the pressure is maximal, but rather to the region where the acoustic beam and thereby the acoustic cavitation activity near the stone surface is the widest.
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Affiliation(s)
- Luc Biasiori-Poulanges
- Institute of Fluid Dynamics, Department of Mechanical and Process Engineering, ETH Zurich, Sonneggstrasse 3, Zurich 8092, Switzerland
| | - Bratislav Lukić
- European Synchrotron Radiation Facility, CS 40220, Grenoble F-38043, France
| | - Outi Supponen
- Institute of Fluid Dynamics, Department of Mechanical and Process Engineering, ETH Zurich, Sonneggstrasse 3, Zurich 8092, Switzerland.
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16
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Hay AN, Vickers ER, Patwardhan M, Gannon J, Ruger L, Allen IC, Vlaisavljevich E, Tuohy J. Investigating cell death responses associated with histotripsy ablation of canine osteosarcoma. Int J Hyperthermia 2023; 40:2279027. [PMID: 38151477 PMCID: PMC10764077 DOI: 10.1080/02656736.2023.2279027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/30/2023] [Indexed: 12/29/2023] Open
Abstract
BACKGROUND Osteosarcoma (OS) is the most frequently occurring primary bone tumor in dogs and people and innovative treatment options are profoundly needed. Histotripsy is an emerging tumor ablation modality, and it is essential for the clinical translation of histotripsy to gain knowledge about the outcome of nonablated tumor cells that could remain postablation. The objective of this study was to characterize the cell death genetic signature and proliferation response of canine OS cells post a near complete histotripsy ablation (96% ± 1.5) and to evaluate genetic cell death signatures associated with histotripsy ablation and OS in vivo. METHODS In the current study, we ablated three canine OS cell lines with a histotripsy dose that resulted in near complete ablation to allow for a viable tumor cell population for downstream analyses. To assess the in vivo cell death genetic signature, we characterized cell death genetic signature in histotripsy-ablated canine OS tumors collected 24-h postablation. RESULTS Differential gene expression changes observed in the 4% viable D17 and D418 cells, and histotripsy-ablated OS tumor samples, but not in Abrams cells, were associated with immunogenic cell death (ICD). The 4% viable OS cells demonstrated significantly reduced proliferation, compared to control OS cells, in vitro. CONCLUSION Histotripsy ablation of OS cell lines leads to direct and potentially indirect cell death as evident by, reduced proliferation in remaining viable OS cells and cell death genetic signatures suggestive of ICD both in vitro and in vivo.
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Affiliation(s)
- Alayna N. Hay
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA, 24061
| | - Elliana R. Vickers
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA, 24061
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061
- Graduate program in Translational, Biology, Medicine, and Health, Virginia Tech, Roanoke, VA, 24016
| | - Manali Patwardhan
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA, 24061
- Graduate program in Translational, Biology, Medicine, and Health, Virginia Tech, Roanoke, VA, 24016
| | - Jessica Gannon
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061
| | - Lauren Ruger
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061
| | - Irving C. Allen
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA, 24061
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061
| | - Joanne Tuohy
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA, 24061
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17
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Edsall C, Fergusson A, Davis RM, Meyer CH, Allen SP, Vlaisavljevich E. Probability of Cavitation in a Custom Iron-Based Coupling Medium for Transcranial Magnetic Resonance-Guided Focused Ultrasound Procedures. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:2519-2526. [PMID: 37730478 PMCID: PMC10591864 DOI: 10.1016/j.ultrasmedbio.2023.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/13/2023] [Accepted: 08/16/2023] [Indexed: 09/22/2023]
Abstract
OBJECTIVE A coupling bath of circulating, chilled, degassed water is essential to safe and precise acoustic transmittance during transcranial magnetic resonance-guided focused ultrasound (tMRgFUS) procedures, but the circulating water impairs the critical real-time magnetic resonance imaging (MRI). An iron-based coupling medium (IBCM) using iron oxide nanoparticles previously developed by our group increased the relaxivity of the coupling bath such that it appears to be invisible on MRI compared with degassed water. However, the nanoparticles also reduced the pressure threshold for cavitation. To address this concern for prefocal cavitation, our group recently developed an IBCM of electrosterically stabilized and aggregation-resistant poly(methacrylic acid)-coated iron oxide nanoparticles (PMAA-FeOX) with a similar capability to reduce the MR signal of degassed water. This study examines the effect of the PMAA-FeOX IBCM on the cavitation threshold. METHODS Increasing concentrations of PMAA-FeOX nanoparticles in degassed, deionized water were placed at the focus of two different transducers to assess low and high duty-cycle pulsing parameters which are representative of two modes of focused ultrasound being investigated for tMRgFUS. Passive cavitation detection and high-speed optical imaging were used to measure cavitation threshold pressures. RESULTS The mean cavitation threshold was determined in both cases to be indistinguishable from the degassed water control, between 6-8 MPa for high duty-cycle pulsing (CW) and between 25.5-26.5 MPa for very low duty-cycle pulsing. CONCLUSION The findings of this study indicate that an IBCM of PMAA-FeOX nanoparticles is a possible solution to reducing MRI interference from the coupling bath without increasing the risk of prefocal cavitation.
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Affiliation(s)
- Connor Edsall
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Austin Fergusson
- Translational Biology, Medicine, and Health Graduate Program, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Richey M Davis
- Department of Chemical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Craig H Meyer
- Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Steven P Allen
- Department of Electrical and Computer Engineering, Brigham Young University, Provo, UT, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA; ICTAS Center for Engineered Health, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
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18
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AIUM Official Statement for the Statement on Biological Effects of Therapeutic Ultrasound. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2023; 42:E68-E73. [PMID: 37584480 DOI: 10.1002/jum.16315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/17/2023]
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19
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Qi T, Jing Y, Deng J, Chang J, Sun W, Yang R, Liu X, Zhang Q, Wan M, Lu M. Boiling Histotripsy Using Dual-Frequency Protocol on Murine Breast Tumor Model and Promotes Immune Activation. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:1773-1785. [PMID: 37871099 DOI: 10.1109/tuffc.2023.3326561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Histotripsy is an ultrasound-guided, noninvasive, nonthermal ablation therapy that can mechanically lyse target tissues. There have been no reports of enhanced histotripsy for large-volume triple-negative breast cancer (TNBC). This study aims to verify the ability of a novel approach of dual-frequency mode combined with two-stage millisecond-length ultrasound pulses (DF-TS) to accelerate the treatment of murine subcutaneous 4T1 tumors and determine immune changes after treatment. A custom-designed 1.1-/2.2-MHz two-element confocal-annular array was used to treat approximately 6-mm tumors under ultrasound guidance and real-time monitoring. Two-stage millisecond-length ultrasound pulses were used to generate approximate cuboid ablation volumes (diagonal 5-6 mm) within each tumor, with a dose of 100 pulses/point. Immune effects were characterized by changes of pro-inflammatory cytokine levels and infiltration levels of immune cells. In all targeted treatment areas, bubble cloud activity was visualized by ultrasound monitoring. The novel protocol resulted in elliptical and controllable sized lesions, reducing the number of scanning points, and was generally well tolerated. After treatment, tumor growth experienced a seven-day stagnation period, the survival period of mice was prolonged, and the levels of pro-inflammatory cytokines and immune cell infiltration increased. This study demonstrates that DF-TS boiling histotripsy (BH) has a noninvasive, efficient, and precise ablation ability for TNBC and potentially enhances immune responses.
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20
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Hay AN, Ruger L, Hsueh A, Vickers E, Klahn S, Vlaisavljevich E, Tuohy J. A review of the development of histotripsy for extremity tumor ablation with a canine comparative oncology model to inform human treatments. Int J Hyperthermia 2023; 40:2274802. [PMID: 37994796 PMCID: PMC10669778 DOI: 10.1080/02656736.2023.2274802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/19/2023] [Indexed: 11/24/2023] Open
Abstract
Cancer is a devasting disease resulting in millions of deaths worldwide in both humans and companion animals, including dogs. Treatment of cancer is complex and challenging and therefore often multifaceted, as in the case of osteosarcoma (OS) and soft tissue sarcoma (STS). OS predominantly involves the appendicular skeleton and STS commonly develops in the extremities, resulting in treatment challenges due to the need to balance wide-margin resections to achieve local oncological control against the functional outcomes for the patient. To achieve wide tumor resection, invasive limb salvage surgery is often required, and the patient is at risk for numerous complications which can ultimately lead to impaired limb function and mobility. The advent of tumor ablation techniques offers the exciting potential of developing noninvasive or minimally invasive treatment options for extremity tumors. One promising innovative tumor ablation technique with strong potential to serve as a noninvasive limb salvage treatment for extremity tumor patients is histotripsy. Histotripsy is a novel, noninvasive, non-thermal, and non-ionizing focused ultrasound technique which uses controlled acoustic cavitation to mechanically disintegrate tissue with high precision. In this review, we present the ongoing development of histotripsy as a non-surgical alternative for extremity tumors and highlight the value of spontaneously occurring OS and STS in the pet dog as a comparative oncology research model to advance this field of histotripsy research.
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Affiliation(s)
- Alayna N. Hay
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA
| | - Lauren Ruger
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Andy Hsueh
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA
| | - Elliana Vickers
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA
- Graduate program in Translation Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA
| | - Shawna Klahn
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Joanne Tuohy
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA
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Park TY, Koh H, Lee W, Park SH, Chang WS, Kim H. Real-Time Acoustic Simulation Framework for tFUS: A Feasibility Study Using Navigation System. Neuroimage 2023; 282:120411. [PMID: 37844771 DOI: 10.1016/j.neuroimage.2023.120411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 10/10/2023] [Accepted: 10/13/2023] [Indexed: 10/18/2023] Open
Abstract
Transcranial focused ultrasound (tFUS), in which acoustic energy is focused on a small region in the brain through the skull, is a non-invasive therapeutic method with high spatial resolution and depth penetration. Image-guided navigation has been widely utilized to visualize the location of acoustic focus in the cranial cavity. However, this system is often inaccurate because of the significant aberrations caused by the skull. Therefore, acoustic simulations using a numerical solver have been widely adopted to compensate for this inaccuracy. Although the simulation can predict the intracranial acoustic pressure field, real-time application during tFUS treatment is almost impossible due to the high computational cost. In this study, we propose a neural network-based real-time acoustic simulation framework and test its feasibility by implementing a simulation-guided navigation (SGN) system. Real-time acoustic simulation is performed using a 3D conditional generative adversarial network (3D-cGAN) model featuring residual blocks and multiple loss functions. This network was trained by the conventional numerical acoustic simulation program (i.e., k-Wave). The SGN system is then implemented by integrating real-time acoustic simulation with a conventional image-guided navigation system. The proposed system can provide simulation results with a frame rate of 5 Hz (i.e., about 0.2 s), including all processing times. In numerical validation (3D-cGAN vs. k-Wave), the average peak intracranial pressure error was 6.8 ± 5.5%, and the average acoustic focus position error was 5.3 ± 7.7 mm. In experimental validation using a skull phantom (3D-cGAN vs. actual measurement), the average peak intracranial pressure error was 4.5%, and the average acoustic focus position error was 6.6 mm. These results demonstrate that the SGN system can predict the intracranial acoustic field according to transducer placement in real-time.
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Affiliation(s)
- Tae Young Park
- Bionics Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Heekyung Koh
- Bionics Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Wonhye Lee
- Bionics Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - So Hee Park
- Department of Neurosurgery, Yeungnam University Medical Center, Daegu 42415, Republic of Korea
| | - Won Seok Chang
- Department of Neurosurgery, Brain Research Institute, Yonsei University College of Medicine, Seoul 04527, Republic of Korea
| | - Hyungmin Kim
- Bionics Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea.
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22
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Edsall C, Huynh L, Hall TL, Vlaisavljevich E. Bubble cloud characteristics and ablation efficiency in dual-frequency intrinsic threshold histotripsy. Phys Med Biol 2023; 68:225006. [PMID: 37797649 PMCID: PMC10627095 DOI: 10.1088/1361-6560/ad00a5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 09/20/2023] [Accepted: 10/05/2023] [Indexed: 10/07/2023]
Abstract
Histotripsy is a non-thermal focused ultrasound ablation method that destroys tissue through the generation and activity of acoustic cavitation bubble clouds. Intrinsic threshold histotripsy uses single-cycle pulses to generate bubble clouds when the dominant negative pressure phase exceeds an intrinsic threshold of ∼25-30 MPa. The ablation efficiency is dependent upon the size and density of bubbles within the bubble cloud. This work investigates the effects of dual-frequency pulsing schemes on the bubble cloud behavior and ablation efficiency in intrinsic threshold histotripsy. A modular 500 kHz:3 MHz histotripsy transducer treated agarose phantoms using dual-frequency histotripsy pulses with a 1:1 pressure ratio from 500 kHz and 3 MHz frequency elements and varying arrival times for the 3 MHz pulse relative to the arrival of the 500 kHz pulse (-100 ns, 0 ns, and +100 ns). High-speed optical imaging captured cavitation effects to characterize bubble cloud and individual bubble dynamics. The effects of dual-frequency pulsing on lesion formation and ablation efficiency were also investigated in red blood cell (RBC) phantoms. Results showed that the single bubble and bubble cloud size for dual-frequency cases were intermediate to published results for the component single-frequencies of 500 kHz and 3 MHz. Additionally, bubble cloud size and dynamics were shown to be altered by the arrival time of the 3 MHz pulse with respect to the 500 kHz pulse, with more uniform cloud expansion and collapse observed for early (-100 ns) arrival. Finally, RBC phantom experiments showed that dual-frequency exposures were capable of generating precise lesions with smaller areas and higher ablation efficiencies than previously published results for 500 kHz or 3 MHz. Overall, results demonstrate dual-frequency histotripsy's ability to modulate bubble cloud size and dynamics can be leveraged to produce precise lesions at higher ablation efficiencies than previously observed for single-frequency pulsing.
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Affiliation(s)
- Connor Edsall
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061, United States of America
| | - Laura Huynh
- Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, 445 Old Turner St., Blacksburg, VA 24061, United States of America
| | - Timothy L Hall
- Biomedical Engineering, University of Michigan, Carl A. Gerstacker Building, 2200 Bonisteel Blvd, Ann Arbor, MI 48109-2133, United States of America
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061, United States of America
- ICTAS Center for Engineered Health, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061, United States of America
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23
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Couillard AB, Zlevor AM, Ziemlewicz TJ, Kisting MA, Knott E, Rossebo AE, White J, Lubner MG, Gettle LM, Hinshaw JL, Mao L, Stoffregen W, Swietlik JF, Knavel-Koepsel E, Stratchko L, Abel EJ, Xu Z, Lee FT, Laeseke PF. A Comparison of Histotripsy and Percutaneous Cryoablation in a Chronic Healthy Swine Kidney Model. J Vasc Interv Radiol 2023; 34:1986-1996. [PMID: 37481064 DOI: 10.1016/j.jvir.2023.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 06/27/2023] [Accepted: 07/13/2023] [Indexed: 07/24/2023] Open
Abstract
PURPOSE To compare the safety and efficacy of histotripsy with cryoablation in a chronic human-scale normal porcine kidney model. MATERIALS AND METHODS Eighteen female domestic swine were divided evenly into histotripsy and cryoablation treatment arms. A planned 2-3 cm diameter treatment was performed under ultrasound (histotripsy) or ultrasound and computed tomography (CT) guidance (cryoablation). Contrast-enhanced CT and serum blood analysis were performed immediately postprocedure and on day 7, with either immediate killing (n = 3) or continued survival to day 30 (n = 6), at which time contrast-enhanced CT, serum blood analysis, and necropsy were performed. Animal welfare, treatment zone appearance, procedure-related adverse events, and histopathology of the treatment zones and surrounding tissues were assessed. RESULTS Histotripsy treatment zones (mean ±standard deviation diameters, 2.7 ± 0.12 × 2.4 ± 0.19 × 2.4 ± 0.26 cm; volume, 8.3 ± 1.9 cm3) were larger than cryoablation zones (mean diameters, 2.2 ± 0.19 × 1.9 ± 0.13 × 1.7 ± 0.19 cm; volume, 3.9 ± 0.8 cm3; P < .001). At 30 days, histotripsy and cryoablation treatment zone volumes decreased by 96% and 83% on CT, respectively (P < .001). Perirenal hematomas were present after 8 of 9 (89%) cryoablation (mean volume, 22.2 cm3) and 1 of 9 (11%, P < .001) histotripsy (volume, 0.4 cm3) procedures, with active arterial extravasation in 4 of 9 (44%) cryoablation and no histotripsy animals (P = .206). All 9 histotripsy animals and 5 of 9 (56%) cryoablation animals had collecting system debris (P = .042). Changes in serum creatinine were similar between the groups (P = .321). CONCLUSIONS Other than a higher rate of bleeding after cryoablation, the safety and early efficacy of histotripsy and cryoablation were comparable for creating treatment zones in a chronic normal porcine kidney model.
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Affiliation(s)
| | - Annie M Zlevor
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - Meridith A Kisting
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Emily Knott
- Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio
| | - Annika E Rossebo
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jim White
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Meghan G Lubner
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - J Louis Hinshaw
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin; Department of Urology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Lu Mao
- Department of Biostatistics, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - John F Swietlik
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - Lindsay Stratchko
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - E Jason Abel
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin; Department of Urology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Fred T Lee
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin; Department of Urology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Paul F Laeseke
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin.
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Li H, He H, Tang J, Luo T, Yang G, Huang L, Dong X, Liu Z. A new sonoablation using acoustic droplet vaporization and focused ultrasound: A feasibility study. Med Phys 2023; 50:6663-6672. [PMID: 37731063 DOI: 10.1002/mp.16742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 08/31/2023] [Accepted: 08/31/2023] [Indexed: 09/22/2023] Open
Abstract
BACKGROUND Histotripsy and boiling histotripsy are two methods of mechanical ablation that use high-pressure focused ultrasound (FUS). PURPOSE Here, a new bubble sonoablation technique was investigated using low-pressure FUS in combination with local injection of perfluoropentane (PFP) in rabbit liver. METHODS Fifteen healthy New Zealand white rabbits were treated with FUS alone, FUS + PFP or PFP alone. FUS was performed using a single-element focused transducer (frequency 596 kHz, 0.27 ms pulses, 0.54% duty cycle, and peak negative pressure 2.0 MPa). Ten minutes before FUS treatment, the PFP droplet was locally injected into the rabbit liver, where the ultrasound was focused. Contrast-enhanced ultrasound (CEUS) of the liver was performed, and the temperature at the liver surface in the targeted liver region was recorded during treatment. The livers were collected for pathological examination. Statistical significance was set at p < 0.05. Paired t-tests were used to compare the pre- and post-treatment values. One-way analysis of variance was performed to compare multiple groups, and the least significant difference method was used for further comparisons between the two groups. RESULTS Analysis of CEUS data showed that the values of area under the curve (AUC) were significantly different in the PFP + FUS group pre- (10453.644 ± 1182.93) and post-treatment (4058.098 ± 2720.41), and the AUC values of PFP + FUS post-treatment (4058.098 ± 2720.41) were also significantly lower than those of the FUS (9946.694 ± 1071.54) and the PFP (10364.794 ± 2181.53) groups. The peak intensity values also showed the same results, the value of peak intensity of PFP+FUS post-treatment was 82.958 ± 13.99, whereas there was no difference between FUS (106.61 ± 7.61) and PFP (104.136 ± 10.55). Hematoxylin and eosin (H&E) staining revealed that the pathological damage ratings of the PFP + FUS, PFP, and FUS groups were grade 3, grade 1, and grade 0, respectively. Specifically, the area of liver necrosis in the PFP + FUS group (0.99 ± 0.29 cm2 ) was 198 times higher than that in the PFP group (0.005 ± 0.008 cm2 ), whereas no necrosis was observed in the livers treated with FUS alone. Simultaneously, the number of vacuoles in the liver of the PFP + FUS group (35.50 ± 23.31) was approximately five times that of the PFP group (7.00 ± 12.88), whereas no vacuoles were found in the liver treated with FUS alone. CONCLUSION PFP droplets combined with FUS can destroy liver tissue and cause tissue necrosis in the droplet injection area, without affecting the structure of surrounding tissue.
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Affiliation(s)
- Hui Li
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Huan He
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Jiawei Tang
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Tingting Luo
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Guoliang Yang
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Leidan Huang
- Department of Ultrasound, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Xiaoxiao Dong
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Zheng Liu
- Department of Ultrasound, The Second Affiliated Hospital of Army Medical University, Chongqing, China
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25
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Hay AN, Imran KM, Hendricks-Wenger A, Gannon JM, Sereno J, Simon A, Lopez VA, Coutermarsh-Ott S, Vlaisavljevich E, Allen IC, Tuohy JL. Ablative and Immunostimulatory Effects of Histotripsy Ablation in a Murine Osteosarcoma Model. Biomedicines 2023; 11:2737. [PMID: 37893110 PMCID: PMC10604356 DOI: 10.3390/biomedicines11102737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/29/2023] [Accepted: 10/02/2023] [Indexed: 10/29/2023] Open
Abstract
Background: Osteosarcoma (OS) is the most frequently occurring malignant bone tumor in humans, primarily affecting children and adolescents. Significant advancements in treatment options for OS have not occurred in the last several decades, and the prognosis remains grim with only a 70% rate of 5-year survival. The objective of this study was to investigate the focused ultrasound technique of histotripsy as a novel, noninvasive treatment option for OS. Methods: We utilized a heterotopic OS murine model to establish the feasibility of ablating OS tumors with histotripsy in a preclinical setting. We investigated the local immune response within the tumor microenvironment (TME) via immune cell phenotyping and gene expression analysis. Findings: We established the feasibility of ablating heterotopic OS tumors with ablation characterized microscopically by loss of cellular architecture in targeted regions of tumors. We observed greater populations of macrophages and dendritic cells within treated tumors and the upregulation of immune activating genes 72 h after histotripsy ablation. Interpretation: This study was the first to investigate histotripsy ablation for OS in a preclinical murine model, with results suggesting local immunomodulation within the TME. Our results support the continued investigation of histotripsy as a novel noninvasive treatment option for OS patients to improve clinical outcomes and patient prognosis.
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Affiliation(s)
- Alayna N. Hay
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA
| | - Khan Mohammad Imran
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA (I.C.A.)
- Translational Biology, Medicine and Health Graduate Research Program, Virginia Tech, Roanoke, VA 24016, USA
| | - Alissa Hendricks-Wenger
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA (I.C.A.)
- Translational Biology, Medicine and Health Graduate Research Program, Virginia Tech, Roanoke, VA 24016, USA
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA (E.V.)
| | - Jessica M. Gannon
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA (E.V.)
| | - Jacqueline Sereno
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA (I.C.A.)
| | - Alex Simon
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA (E.V.)
| | - Victor A. Lopez
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA (E.V.)
| | - Sheryl Coutermarsh-Ott
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA (I.C.A.)
- Virginia Department of Agriculture and Consumer Services, Wytheville, VA 24382, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA (E.V.)
| | - Irving C. Allen
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA (I.C.A.)
- Translational Biology, Medicine and Health Graduate Research Program, Virginia Tech, Roanoke, VA 24016, USA
| | - Joanne L. Tuohy
- Department of Small Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Blacksburg, VA 24061, USA
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Mondou P, Mériaux S, Nageotte F, Vappou J, Novell A, Larrat B. State of the art on microbubble cavitation monitoring and feedback control for blood-brain-barrier opening using focused ultrasound. Phys Med Biol 2023; 68:18TR03. [PMID: 37369229 DOI: 10.1088/1361-6560/ace23e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Focused ultrasound (FUS) is a non-invasive and highly promising method for targeted and reversible blood-brain barrier permeabilization. Numerous preclinical studies aim to optimize the localized delivery of drugs using this method in rodents and non-human primates. Several clinical trials have been initiated to treat various brain diseases in humans using simultaneous BBB permeabilization and drug injection. This review presents the state of the art ofin vitroandin vivocavitation control algorithms for BBB permeabilization using microbubbles (MB) and FUS. Firstly, we describe the different cavitation states, their physical significance in terms of MB behavior and their translation into the spectral composition of the backscattered signal. Next, we report the different indexes calculated and used during the ultrasonic monitoring of cavitation. Finally, the differentin vitroandin vivocavitation control strategies described in the literature are presented and compared.
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Affiliation(s)
- Paul Mondou
- Université de Strasbourg, CNRS, ICube, UMR7357, Strasbourg, France
- Université Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, 91191, Gif-sur-Yvette, France
| | - Sébastien Mériaux
- Université Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, 91191, Gif-sur-Yvette, France
| | - Florent Nageotte
- Université de Strasbourg, CNRS, ICube, UMR7357, Strasbourg, France
| | - Jonathan Vappou
- Université de Strasbourg, CNRS, ICube, UMR7357, Strasbourg, France
| | - Anthony Novell
- Université Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, 91191, Gif-sur-Yvette, France
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, 91401 , Orsay, France
| | - Benoit Larrat
- Université Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, 91191, Gif-sur-Yvette, France
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27
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Trivedi VV, Wallach EL, Bader KB, Shekhar H. Contrast-Enhanced Imaging of Histotripsy Bubble Clouds Using Chirp-Coded Excitation and Volterra Filtering. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:989-998. [PMID: 37379172 DOI: 10.1109/tuffc.2023.3289918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Histotripsy is a focused ultrasound therapy that ablates tissue via bubble cloud activity. Real-time ultrasound image guidance is used to ensure safe and effective treatment. Plane-wave imaging enables tracking of histotripsy bubble clouds at a high frame rate but lacks adequate contrast. Furthermore, bubble cloud hyperechogenicity is reduced in abdominal targets, making the development of contrast-specific sequences for deep-seated targets an active area of research. Chirp-coded subharmonic imaging was reported previously to enhance histotripsy bubble cloud detection by a modest 4-6 dB compared to the conventional sequence. Incorporating additional steps into the signal processing pipeline could enhance bubble cloud detection and tracking. In this study, we evaluated the feasibility of combining chirp-coded subharmonic imaging with Volterra filtering for enhancing bubble cloud detection in vitro. Chirped imaging pulses were used to track bubble clouds generated in scattering phantoms at a 1-kHz frame rate. Fundamental and subharmonic matched filters were applied to the received radio frequency signals, followed by a tuned Volterra filter to extract bubble-specific signatures. For subharmonic imaging, the application of the quadratic Volterra filter improved the contrast-to-tissue ratio from 5.18 ± 1.29 to 10.90 ± 3.76 dB, relative to the application of the subharmonic matched filter. These findings demonstrate the utility of the Volterra filter for histotripsy image guidance.
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Edsall C, Huynh L, Hall T, Vlaisavljevich E. Bubble Cloud Characteristics and Ablation Efficiency in Dual-Frequency Intrinsic Threshold Histotripsy. ARXIV 2023:arXiv:2307.03245v1. [PMID: 37461413 PMCID: PMC10350103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Histotripsy is a non-thermal focused ultrasound ablation method that destroys tissue through the generation and activity of acoustic cavitation bubble clouds. Intrinsic threshold histotripsy uses single-cycle pulses to generate bubble clouds when the dominant negative pressure phase exceeds an intrinsic threshold of ~25-30 MPa. The ablation efficiency is dependent upon the size and density of bubbles within the bubble cloud. This work investigates the effects of dual-frequency pulsing schemes on the bubble cloud behavior and ablation efficiency in intrinsic threshold histotripsy. A modular 500 kHz:3 MHz histotripsy transducer treated agarose phantoms using dual-frequency histotripsy pulses with a 1:1 pressure ratio from 500 kHz and 3 MHz frequency elements and varying arrival times for the 3 MHz pulse relative to the arrival of the 500 kHz pulse (-100 ns, 0 ns, and +100 ns). High-speed optical imaging captured cavitation effects to characterize bubble cloud and individual bubble dynamics. The effects of dual-frequency pulsing on lesion formation and ablation efficiency were also investigated in red blood cell (RBC) phantoms. Results showed that the single bubble and bubble cloud size for dual-frequency cases were intermediate to published results for the component single frequencies of 500 kHz and 3 MHz. Additionally, bubble cloud size and dynamics were shown to be altered by the arrival time of the 3 MHz pulse with respect to the 500 kHz pulse, with more uniform cloud expansion and collapse observed for early (-100 ns) arrival. Finally, RBC phantom experiments showed that dual-frequency exposures were capable of generating precise lesions with smaller areas and higher ablation efficiencies than previously published results for 500 kHz or 3 MHz. Overall, results demonstrate dual-frequency histotripsy's ability to modulate bubble cloud size and dynamics can be leveraged to produce precise lesions at higher ablation efficiencies than previously observed for single-frequency pulsing.
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Affiliation(s)
- Connor Edsall
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061
| | - Laura Huynh
- Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, 445 Old Turner St., Blacksburg, VA 24061
| | - Tim Hall
- Biomedical Engineering, University of Michigan, Carl A. Gerstacker Building, 2200 Bonisteel Blvd, Ann Arbor, MI 48109-2133, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061
- ICTAS Center for Engineered Health, Virginia Polytechnic Institute and State University, 325 Stanger St., Blacksburg, VA, 24061
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29
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Bader KB, Flores Basterrechea K, Hendley SA. In silico assessment of histotripsy-induced changes in catheter-directed thrombolytic delivery. Front Physiol 2023; 14:1225804. [PMID: 37449013 PMCID: PMC10336328 DOI: 10.3389/fphys.2023.1225804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction: For venous thrombosis patients, catheter-directed thrombolytic therapy is the standard-of-care to recanalize the occluded vessel. Limitations with thrombolytic drugs make the development of adjuvant treatments an active area of research. One potential adjuvant is histotripsy, a focused ultrasound therapy that lyses red blood cells within thrombus via the spontaneous generation of bubbles. Histotripsy has also been shown to improve the efficacy of thrombolytic drugs, though the precise mechanism of enhancement has not been elucidated. In this study, in silico calculations were performed to determine the contribution of histotripsy-induced changes in thrombus diffusivity to alter catheter-directed therapy. Methods: An established and validated Monte Carlo calculation was used to predict the extent of histotripsy bubble activity. The distribution of thrombolytic drug was computed with a finite-difference time domain (FDTD) solution of the perfusion-diffusion equation. The FDTD calculation included changes in thrombus diffusivity based on outcomes of the Monte Carlo calculation. Fibrin degradation was determined using the known reaction rate of thrombolytic drug. Results: In the absence of histotripsy, thrombolytic delivery was restricted in close proximity to the catheter. Thrombolytic perfused throughout the focal region for calculations that included the effects of histotripsy, resulting in an increased degree of fibrinolysis. Discussion: These results were consistent with the outcomes of in vitro studies, suggesting histotripsy-induced changes in the thrombus diffusivity are a primary mechanism for enhancement of thrombolytic drugs.
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Affiliation(s)
- Kenneth B. Bader
- Department of Radiology, University of Chicago, Chicago, IL, United States
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30
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Kagami S, Kanagawa T. Weakly nonlinear focused ultrasound in viscoelastic media containing multiple bubbles. ULTRASONICS SONOCHEMISTRY 2023; 97:106455. [PMID: 37271029 DOI: 10.1016/j.ultsonch.2023.106455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 06/06/2023]
Abstract
To facilitate practical medical applications such as cancer treatment utilizing focused ultrasound and bubbles, a mathematical model that can describe the soft viscoelasticity of human body, the nonlinear propagation of focused ultrasound, and the nonlinear oscillations of multiple bubbles is theoretically derived and numerically solved. The Zener viscoelastic model and Keller-Miksis bubble equation, which have been used for analyses of single or few bubbles in viscoelastic liquid, are used to model the liquid containing multiple bubbles. From the theoretical analysis based on the perturbation expansion with the multiple-scales method, the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, which has been used as a mathematical model of weakly nonlinear propagation in single phase liquid, is extended to viscoelastic liquid containing multiple bubbles. The results show that liquid elasticity decreases the magnitudes of the nonlinearity, dissipation, and dispersion of ultrasound and increases the phase velocity of the ultrasound and linear natural frequency of the bubble oscillation. From the numerical calculation of resultant KZK equation, the spatial distribution of the liquid pressure fluctuation for the focused ultrasound is obtained for cases in which the liquid is water or liver tissue. In addition, frequency analysis is carried out using the fast Fourier transform, and the generation of higher harmonic components is compared for water and liver tissue. The elasticity supresses the generation of higher harmonic components and promotes the remnant of the fundamental frequency components. This indicates that the elasticity of liquid suppresses shock wave formation in practical applications.
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Affiliation(s)
- Shunsuke Kagami
- Department of Engineering Mechanics and Energy, Degree Program of Systems and Information Engineering, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan.
| | - Tetsuya Kanagawa
- Department of Engineering Mechanics and Energy, Degree Program of Systems and Information Engineering, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan.
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31
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Yeats E, Lu N, Sukovich JR, Xu Z, Hall TL. Soft Tissue Aberration Correction for Histotripsy Using Acoustic Emissions From Cavitation Cloud Nucleation and Collapse. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:1182-1193. [PMID: 36759271 PMCID: PMC10082475 DOI: 10.1016/j.ultrasmedbio.2023.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 12/01/2022] [Accepted: 01/03/2023] [Indexed: 05/11/2023]
Abstract
OBJECTIVE Phase aberration from soft tissue limits the efficacy of histotripsy, a therapeutic ultrasound technique based on acoustic cavitation. Previous work has shown that the acoustic emissions from cavitation can serve as "point sources" for aberration correction (AC). This study compared the efficacy of soft tissue AC for histotripsy using acoustic cavitation emissions (ACE) from bubble cloud nucleation and collapse. METHODS A 750-kHz, receive-capable histotripsy array was pulsed to generate cavitation in ex vivo porcine liver through an intervening abdominal wall. Received ACE signals were used to determine the arrival time differences to the focus and compute corrective delays. Corrections from single pulses and from the median of multiple pulses were tested. DISCUSSION On average, ACE AC obtained 96% ± 3% of the pressure amplitude obtained by hydrophone-based correction (compared with 71% ± 5% without AC). Both nucleation- and collapse-based corrections obtained >96% of the hydrophone-corrected pressure when using medians of ≥10 pulses. When using single-pulse corrections, nucleation obtained a range of 49%-99% of the hydrophone-corrected pressure, while collapse obtained 95%-99%. CONCLUSION The results suggest that (i) ACE AC can recover nearly all pressure amplitude lost owing to soft tissue aberration and that (ii) the collapse signal permits robust AC using a small number of pulses.
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Affiliation(s)
- Ellen Yeats
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
| | - Ning Lu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Jonathan R Sukovich
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Timothy L Hall
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
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Yamaguchi T, Nakano M, Sasanuma J, Takasaki M, Maki F, Hino S, Kaburagi M, Iijima K, Iwamuro H, Watanabe K. Cavitation with low-energy sonication during focused ultrasound thalamotomy for a patient with tremor-dominant Parkinson's disease: a potential risk. Acta Neurochir (Wien) 2023; 165:1195-1200. [PMID: 36917360 DOI: 10.1007/s00701-023-05551-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/02/2023] [Indexed: 03/16/2023]
Abstract
We report a patient with tremor-dominant Parkinson's disease who had a mild cavitation bioeffect during magnetic resonance-guided focused ultrasound thalamotomy. During the aligning phase with low-energy sonication, cavitation caused mild dysarthria and paresthesia, prompting treatment cessation. At the same time, tremor and rigidity improved. MRI revealed extensive high-intensity lesions in the thalamus 1 day after the procedure followed by steroid infusion, which resulted in resolution of adverse events. Tremor and rigidity improved 1.5 years after the procedure. Although cavitation can relieve tremors and rigidity, it should be carefully monitored due to potential permanent adverse events by unpredictable and unknown behaviors.
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Affiliation(s)
- Toshio Yamaguchi
- International Academia for Focused Ultrasound Therapy, Katahira, Asaoku, Kawasaki, Kanagawa, 215-0023, Japan. .,Research Institute of Diagnostic Radiology, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan.
| | - Masayuki Nakano
- Department of Neurosurgery, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Jinichi Sasanuma
- Department of Neurosurgery, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Masahito Takasaki
- Department of Anesthesiology, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Futaba Maki
- Department of Neurology, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Sakae Hino
- Department of Neurology, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Mayumi Kaburagi
- Department of Neurology, Shin-Yurigaoka General Hospital, Kawasaki, Kanagawa, Japan
| | - Ken Iijima
- International Academia for Focused Ultrasound Therapy, Katahira, Asaoku, Kawasaki, Kanagawa, 215-0023, Japan
| | - Hirokazu Iwamuro
- Department of Neurosurgery, Juntendo University, Bunkyo City, Tokyo, Japan
| | - Kazuo Watanabe
- Southern Tohoku Research Institute for Neuroscience, Koriyama, Fukushima, Japan
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Hu Y, Wei J, Shen Y, Chen S, Chen X. Barrier-breaking effects of ultrasonic cavitation for drug delivery and biomarker release. ULTRASONICS SONOCHEMISTRY 2023; 94:106346. [PMID: 36870921 PMCID: PMC10040969 DOI: 10.1016/j.ultsonch.2023.106346] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/15/2023] [Accepted: 02/23/2023] [Indexed: 05/27/2023]
Abstract
Recently, emerging evidence has demonstrated that cavitation actually creates important bidirectional channels on biological barriers for both intratumoral drug delivery and extratumoral biomarker release. To promote the barrier-breaking effects of cavitation for both therapy and diagnosis, we first reviewed recent technical advances of ultrasound and its contrast agents (microbubbles, nanodroplets, and gas-stabilizing nanoparticles) and then reported the newly-revealed cavitation physical details. In particular, we summarized five types of cellular responses of cavitation in breaking the plasma membrane (membrane retraction, sonoporation, endocytosis/exocytosis, blebbing and apoptosis) and compared the vascular cavitation effects of three different types of ultrasound contrast agents in breaking the blood-tumor barrier and tumor microenvironment. Moreover, we highlighted the current achievements of the barrier-breaking effects of cavitation in mediating drug delivery and biomarker release. We emphasized that the precise induction of a specific cavitation effect for barrier-breaking was still challenged by the complex combination of multiple acoustic and non-acoustic cavitation parameters. Therefore, we provided the cutting-edge in-situ cavitation imaging and feedback control methods and suggested the development of an international cavitation quantification standard for the clinical guidance of cavitation-mediated barrier-breaking effects.
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Affiliation(s)
- Yaxin Hu
- School of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, Guangdong, 518060, PR China; National-regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen University, Shenzhen, Guangdong, 518060, PR China
| | - Jianpeng Wei
- School of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, Guangdong, 518060, PR China; National-regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen University, Shenzhen, Guangdong, 518060, PR China
| | - Yuanyuan Shen
- School of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, Guangdong, 518060, PR China; National-regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen University, Shenzhen, Guangdong, 518060, PR China
| | - Siping Chen
- School of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, Guangdong, 518060, PR China; National-regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen University, Shenzhen, Guangdong, 518060, PR China
| | - Xin Chen
- School of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, Guangdong, 518060, PR China; National-regional Key Technology Engineering Laboratory for Medical Ultrasound, Shenzhen University, Shenzhen, Guangdong, 518060, PR China.
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Ruger L, Yang E, Gannon J, Sheppard H, Coutermarsh-Ott S, Ziemlewicz TJ, Dervisis N, Allen IC, Daniel GB, Tuohy J, Vlaisavljevich E, Klahn S. Mechanical High-Intensity Focused Ultrasound (Histotripsy) in Dogs With Spontaneously Occurring Soft Tissue Sarcomas. IEEE Trans Biomed Eng 2023; 70:768-779. [PMID: 36006886 PMCID: PMC9969335 DOI: 10.1109/tbme.2022.3201709] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
INTRODUCTION Histotripsy is a non-invasive focused ultrasound therapy that uses controlled acoustic cavitation to mechanically disintegrate tissue. To date, there are no reports investigating histotripsy for the treatment of soft tissue sarcoma (STS). OBJECTIVE This study aimed to investigate the in vivo feasibility of ablating STS with histotripsy and to characterize the impact of partial histotripsy ablation on the acute immunologic response in canine patients with spontaneous STS. METHODS A custom 500 kHz histotripsy system was used to treat ten dogs with naturally occurring STS. Four to six days after histotripsy, tumors were surgically resected. Safety was determined by monitoring vital signs during treatment and post-treatment physical examinations, routine lab work, and owners' reports. Ablation was characterized using radiologic and histopathologic analyses. Systemic immunological impact was evaluated by measuring changes in cytokine concentrations, and tumor microenvironment changes were evaluated by characterizing changes in infiltration with tumor-associated macrophages (TAMs) and tumor-infiltrating lymphocytes (TILs) using multiplex immunohistochemistry and differential gene expression. RESULTS Results showed histotripsy ablation was achievable and well-tolerated in all ten dogs. Immunological results showed histotripsy induced pro-inflammatory changes in the tumor microenvironment. Conclusion & Significance: Overall, this study demonstrates histotripsy's potential as a precise, non-invasive treatment for STS.
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Knott EA, Zlevor AM, Hinshaw JL, Laeseke PF, Longhurst C, Frank J, Bradley CW, Couillard AB, Rossebo AE, Xu Z, Lee FT, Ziemlewicz TJ. A comparison study of microwave ablation vs. histotripsy for focal liver treatments in a swine model. Eur Radiol 2023; 33:1050-1062. [PMID: 36048208 DOI: 10.1007/s00330-022-09112-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/06/2022] [Accepted: 08/11/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To compare the acute and chronic safety and treatment effects of non-invasive hepatic histotripsy vs. percutaneous microwave (MW) ablation in a healthy porcine model. METHODS This was a dual-arm study in which each animal (n = 14) received either a single hepatic microwave (n = 6) or histotripsy (n = 6 single treatment; n = 2 double treatment) under ultrasound guidance. The goal was to create 2.5-3.0 cm short-axis treatments in similar locations across modalities. Animals were survived for 1 month with contrast-enhanced CT imaging on days 0, 2, 7, 14, and 28. On day 28, necropsy and histopathology were performed. RESULTS All procedures were well-tolerated. MW ablation zones were longer and more oblong, but equivalent in the short axes to histotripsy zones on immediate post-procedure CT (p < 0.001 and p = 0.45, respectively). Overall, MW volumes were larger (21.4 cm3 vs. 13.4 cm3; p = 0.001) and histotripsy treatment zones were more spherical (p = 0.007). Histotripsy zones were close to the prescribed size (p < 0.001). Over the study period, histotripsy treatment zones decreased in volume while microwave ablation zones slightly increased (-83% vs. +17%, p = 0.001). There were several imaging-only findings: Branch portal vein thrombus with both histotripsy (7/8) and MW (6/6), hematoma in 2/6 MW only, and a gallbladder injury in 1/6 MW animals. The ablation zones demonstrated complete cellular destruction for both modalities. CONCLUSION Histotripsy was associated with more spherical treatments, fewer biliary complications, and greater treatment zone involution. Hepatic MW and histotripsy treatment in a normal porcine model appear at least equally effective for creating treatment zones with a similar safety profile. KEY POINTS • Microwave ablation and histotripsy for liver treatment in a healthy porcine model yield equivalent procedural tolerance and cellular destruction. • Histotripsy was associated with more spherical treatments, fewer biliary complications, and greater treatment zone involution over the 28-day follow-up period. • These findings confirm the safety and efficacy of hepatic histotripsy and support the pursuit of clinical trials to further evaluate the translatability of these results.
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Affiliation(s)
- Emily A Knott
- The Cleveland Clinic Lerner College of Medicine, Cleveland, OH, USA
| | - Annie M Zlevor
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
| | - J Louis Hinshaw
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
- Department of Urology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Paul F Laeseke
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
| | - Colin Longhurst
- Biostatistics and Medical Informatics, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Jenifer Frank
- College of Agriculture and Life Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Charles W Bradley
- Department of Pathobiology, University of Pennsylvania: School of Veterinary Medicine, Philadelphia, PA, USA
| | - Allison B Couillard
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
| | - Annika E Rossebo
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Fred T Lee
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
- Department of Urology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
- College of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Timothy J Ziemlewicz
- Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA.
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Ruger LN, Hay AN, Vickers ER, Coutermarsh-Ott SL, Gannon JM, Covell HS, Daniel GB, Laeseke PF, Ziemlewicz TJ, Kierski KR, Ciepluch BJ, Vlaisavljevich E, Tuohy JL. Characterizing the Ablative Effects of Histotripsy for Osteosarcoma: In Vivo Study in Dogs. Cancers (Basel) 2023; 15:cancers15030741. [PMID: 36765700 PMCID: PMC9913343 DOI: 10.3390/cancers15030741] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
Osteosarcoma (OS) is a malignant bone tumor treated by limb amputation or limb salvage surgeries and chemotherapy. Histotripsy is a non-thermal, non-invasive focused ultrasound therapy using controlled acoustic cavitation to mechanically disintegrate tissue. Recent ex vivo and in vivo pilot studies have demonstrated the ability of histotripsy for ablating OS but were limited in scope. This study expands on these initial findings to more fully characterize the effects of histotripsy for bone tumors, particularly in tumors with different compositions. A prototype 500 kHz histotripsy system was used to treat ten dogs with suspected OS at an intermediate treatment dose of 1000 pulses per location. One day after histotripsy, treated tumors were resected via limb amputation, and radiologic and histopathologic analyses were conducted to determine the effects of histotripsy for each patient. The results of this study demonstrated that histotripsy ablation is safe and feasible in canine patients with spontaneous OS, while offering new insights into the characteristics of the achieved ablation zone. More extensive tissue destruction was observed after histotripsy compared to that in previous reports, and radiographic changes in tumor size and contrast uptake following histotripsy were reported for the first time. Overall, this study significantly expands our understanding of histotripsy bone tumor ablation and informs future studies for this application.
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Affiliation(s)
- Lauren N. Ruger
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
| | - Alayna N. Hay
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
| | - Elliana R. Vickers
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
- Graduate Program in Translational Biology, Medicine, and Health, Virginia Polytechnic Institute and State University, Roanoke, VA 24016, USA
| | - Sheryl L. Coutermarsh-Ott
- Department of Biological Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
| | - Jessica M. Gannon
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
| | - Hannah S. Covell
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
| | - Gregory B. Daniel
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
| | - Paul F. Laeseke
- Department of Radiology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | | | - Katharine R. Kierski
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
| | - Brittany J. Ciepluch
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24016, USA
- Correspondence: (E.V.); (J.L.T.)
| | - Joanne L. Tuohy
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24016, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland Regional College of Veterinary Medicine, Roanoke, VA 24016, USA
- Correspondence: (E.V.); (J.L.T.)
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Williams RP, Simon JC, Khokhlova VA, Sapozhnikov OA, Khokhlova TD. The histotripsy spectrum: differences and similarities in techniques and instrumentation. Int J Hyperthermia 2023; 40:2233720. [PMID: 37460101 PMCID: PMC10479943 DOI: 10.1080/02656736.2023.2233720] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/15/2023] [Accepted: 07/02/2023] [Indexed: 07/20/2023] Open
Abstract
Since its inception about two decades ago, histotripsy - a non-thermal mechanical tissue ablation technique - has evolved into a spectrum of methods, each with distinct potentiating physical mechanisms: intrinsic threshold histotripsy, shock-scattering histotripsy, hybrid histotripsy, and boiling histotripsy. All methods utilize short, high-amplitude pulses of focused ultrasound delivered at a low duty cycle, and all involve excitation of violent bubble activity and acoustic streaming at the focus to fractionate tissue down to the subcellular level. The main differences are in pulse duration, which spans microseconds to milliseconds, and ultrasound waveform shape and corresponding peak acoustic pressures required to achieve the desired type of bubble activity. In addition, most types of histotripsy rely on the presence of high-amplitude shocks that develop in the pressure profile at the focus due to nonlinear propagation effects. Those requirements, in turn, dictate aspects of the instrument design, both in terms of driving electronics, transducer dimensions and intensity limitations at surface, shape (primarily, the F-number) and frequency. The combination of the optimized instrumentation and the bio-effects from bubble activity and streaming on different tissues, lead to target clinical applications for each histotripsy method. Here, the differences and similarities in the physical mechanisms and resulting bioeffects of each method are reviewed and tied to optimal instrumentation and clinical applications.
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Affiliation(s)
- Randall P Williams
- Division of Gastroenterology, Department of Medicine, University of Washington, Seattle, WA, USA
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
| | - Julianna C Simon
- Graduate Program in Acoustics, The Pennsylvania State University, University Park, PA, USA
| | - Vera A Khokhlova
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
- Department of Acoustics, Physics Faculty, Moscow State University, Moscow, Russia
| | - Oleg A Sapozhnikov
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
- Department of Acoustics, Physics Faculty, Moscow State University, Moscow, Russia
| | - Tatiana D Khokhlova
- Division of Gastroenterology, Department of Medicine, University of Washington, Seattle, WA, USA
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
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Stettinius A, Holmes H, Zhang Q, Mehochko I, Winters M, Hutchison R, Maxwell A, Holliday J, Vlaisavljevich E. DNA release from plant tissue using focused ultrasound extraction (FUSE). APPLICATIONS IN PLANT SCIENCES 2023; 11:e11510. [PMID: 36818781 PMCID: PMC9934592 DOI: 10.1002/aps3.11510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 06/18/2023]
Abstract
PREMISE Sample preparation in genomics is a critical step that is often overlooked in molecular workflows and impacts the success of downstream genetic applications. This study explores the use of a recently developed focused ultrasound extraction (FUSE) technique to enable the rapid release of DNA from plant tissues for genetic analysis. METHODS FUSE generates a dense acoustic cavitation bubble cloud that pulverizes targeted tissue into acellular debris. This technique was applied to leaf samples of American chestnut (Castanea dentata), tulip poplar (Liriodendron tulipifera), red maple (Acer rubrum), and chestnut oak (Quercus montana). RESULTS We observed that FUSE can extract high quantities of DNA in 9-15 min, compared to the 30 min required for control DNA extraction methods. FUSE extracted DNA quantities of 24.33 ± 6.51 ng/mg and 35.32 ± 9.21 ng/mg from American chestnut and red maple, respectively, while control methods yielded 6.22 ± 0.87 ng/mg and 11.51 ± 1.95 ng/mg, respectively. The quality of the DNA released by FUSE allowed for successful amplification and next-generation sequencing. DISCUSSION These results indicate that FUSE can improve DNA extraction efficiency for leaf tissues. Continued development of this technology aims to adapt to field-deployable systems to increase the cataloging of genetic biodiversity, particularly in low-resource biodiversity hotspots.
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Affiliation(s)
- Alexia Stettinius
- Department of Biomedical Engineering and MechanicsVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | - Hal Holmes
- Department of Biomedical Engineering and MechanicsVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
- Conservation X LabsSeattleWashingtonUSA
| | - Qian Zhang
- Department of Forest Resources and Environmental ConservationVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | - Isabelle Mehochko
- Department of Biomedical Engineering and MechanicsVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | | | - Ruby Hutchison
- Department of Biomedical Engineering and MechanicsVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | - Adam Maxwell
- Department of UrologyUniversity of WashingtonSeattleWashingtonUSA
| | - Jason Holliday
- Department of Forest Resources and Environmental ConservationVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and MechanicsVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
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Ruger L, Yang E, Coutermarsh-Ott S, Vickers E, Gannon J, Nightengale M, Hsueh A, Ciepluch B, Dervisis N, Vlaisavljevich E, Klahn S. Histotripsy ablation for the treatment of feline injection site sarcomas: a first-in-cat in vivo feasibility study. Int J Hyperthermia 2023; 40:2210272. [PMID: 37196996 DOI: 10.1080/02656736.2023.2210272] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/28/2023] [Accepted: 04/28/2023] [Indexed: 05/19/2023] Open
Abstract
PURPOSE Feline soft tissue sarcoma (STS) and injection site sarcoma (fISS) are rapidly growing tumors with low metastatic potential, but locally aggressive behavior. Histotripsy is a non-invasive focused ultrasound therapy using controlled acoustic cavitation to mechanically disintegrate tissue. In this study, we investigated the in vivo safety and feasibility of histotripsy to treat fISS using a custom 1 MHz transducer. MATERIALS AND METHODS Three cats with naturally-occurring STS were treated with histotripsy before surgical removal of the tumor 3 to 6 days later. Gross and histological analyses were used to characterize the ablation efficacy of the treatment, and routine immunohistochemistry and batched cytokine analysis were used to investigate the acute immunological effects of histotripsy. RESULTS Results showed that histotripsy ablation was achievable and well-tolerated in all three cats. Precise cavitation bubble clouds were generated in all patients, and hematoxylin & eosin stained tissues revealed ablative damage in targeted regions. Immunohistochemical results identified an increase in IBA-1 positive cells in treated tissues, and no significant changes in cytokine concentrations were identified post-treatment. CONCLUSIONS Overall, the results of this study demonstrate the safety and feasibility of histotripsy to target and ablate superficial feline STS and fISS tumors and guide the clinical development of histotripsy devices for this application.
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Affiliation(s)
- Lauren Ruger
- Department of Biomedical Engineering and Mechanics, VA Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Ester Yang
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
| | - Sheryl Coutermarsh-Ott
- Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Elliana Vickers
- Department of Biomedical Engineering and Mechanics, VA Polytechnic Institute and State University, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
- Graduate Program in Translational Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA, USA
| | - Jessica Gannon
- Department of Biomedical Engineering and Mechanics, VA Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Marlie Nightengale
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
| | - Andy Hsueh
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
| | - Brittany Ciepluch
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
| | - Nikolaos Dervisis
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
- Department of Internal Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, VA Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Shawna Klahn
- Department of Small Animal Clinical Sciences, Virginia-MD College of Veterinary Medicine, Blacksburg, VA, USA
- Virginia Tech Animal Cancer Care and Research Center, Virginia-Maryland College of Veterinary Medicine, Roanoke, VA, USA
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Iwanicki I, Wu LL, Flores-Guzman F, Sundland R, Viza-Gomes P, Nordgren R, Centner CS, Kandel JJ, Applebaum MA, Bader KB, Hernandez SL. Histotripsy induces apoptosis and reduces hypoxia in a neuroblastoma xenograft model. Int J Hyperthermia 2023; 40:2222941. [PMID: 37344380 DOI: 10.1080/02656736.2023.2222941] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/09/2023] [Accepted: 06/05/2023] [Indexed: 06/23/2023] Open
Abstract
BACKGROUND Neuroblastoma (NB) is the most common extracranial solid tumor of childhood, and high-risk disease is resistant to intensive treatment. Histotripsy is a focused ultrasound therapy under development for tissue ablation via bubble activity. The goal of this study was to assess outcomes of histotripsy ablation in a xenograft model of high-risk NB. METHODS Female NCr nude mice received NGP-luciferase cells intrarenally. Under ultrasound image guidance, histotripsy pulses were applied over a distance of 4-6 mm within the tumors. Bioluminescence indicative of tumor viability was quantified before, immediately after, and 24 h after histotripsy exposure. Tumors were immunostained to assess apoptosis (TUNEL), endothelium (endomucin), pericytes (αSMA), hypoxia (pimonidazole), vascular endothelial growth factor A (VEGFA), and platelet-derived growth factor-B (PDGF-B). The apoptotic cytokine TNFα and its downstream effector cleaved caspase-3 (c-casp-3) were assessed with SDS-PAGE. RESULTS Histotripsy induced a 50% reduction in bioluminescence compared to untreated controls, with an absence of nuclei in the treatment core surrounded by a dense rim of TUNEL-positive cells. Tumor regions not targeted by histotripsy also showed an increase in TUNEL staining density. Increased apoptosis in histotripsy samples was consistent with increases in TNFα and c-casp-3 relative to controls. Treated tumors exhibited a decrease in hypoxia, VEGF, PDGF-B, and pericyte coverage of vasculature compared to control samples. Further, increases in vasodilation were found in histotripsy-treated specimens. CONCLUSIONS In addition to ablative effects, histotripsy was found to drive tumor apoptosis through intrinsic pathways, altering blood vessel architecture, and reducing hypoxia.
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Affiliation(s)
- Isabella Iwanicki
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Lydia L Wu
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Fernando Flores-Guzman
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Rachael Sundland
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Paula Viza-Gomes
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Rachel Nordgren
- Department of Public Health Sciences, The University of Chicago, Chicago, IL
| | | | - Jessica J Kandel
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
| | - Mark A Applebaum
- Department of Pediatrics, Section of Hematology/Oncology, The University of Chicago, Chicago, IL
| | - Kenneth B Bader
- Department of Radiology, The University of Chicago, Chicago, IL
| | - Sonia L Hernandez
- Department of Surgery, Section of Pediatric Surgery, The University of Chicago, Chicago, IL, USA
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Imran KM, Ganguly A, Paul T, Powar M, Vlaisavljevich E, Cho CS, Allen IC. Magic bubbles: utilizing histotripsy to modulate the tumor microenvironment and improve systemic anti-tumor immune responses. Int J Hyperthermia 2023; 40:2244206. [PMID: 37580047 PMCID: PMC10430775 DOI: 10.1080/02656736.2023.2244206] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/16/2023] Open
Abstract
Focused Ultrasound (FUS) is emerging as a promising primary and adjunct therapy for the treatment of cancer. This includes histotripsy, which is a noninvasive, non-ionizing, non-thermal ultrasound guided ablation modality. As histotripsy has progressed from bench-to-bedside, it has become evident that this therapy has benefits beyond local tumor ablation. Specifically, histotripsy has the potential to shift the local tumor microenvironment from immunologically 'cold' to 'hot'. This is associated with the production of damage associated molecular patterns, the release of a selection of proinflammatory mediators, and the induction of inflammatory forms of cell death in cells just outside of the treatment zone. In addition to the induction of this innate immune response, histotripsy can also improve engagement of the adaptive immune system and promote systemic anti-tumor immunity targeting distal tumors and metastatic lesions. These tantalizing observations suggest that, in settings of widely metastatic disease burden, selective histotripsy of a limited number of accessible tumors could be a means of maximizing responsiveness to systemic immunotherapy. More work is certainly needed to optimize treatment strategies that best synergize histotripsy parameters with innate and adaptive immune responses. Likewise, rigorous clinical studies are still necessary to verify the presence and repeatability of these phenomena in human patients. As this technology nears regulatory approval for clinical use, it is our expectation that the insights and immunomodulatory mechanisms summarized in this review will serve as directional guides for rational clinical studies to validate and optimize the potential immunotherapeutic role of histotripsy tumor ablation.
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Affiliation(s)
- Khan M. Imran
- Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Roanoke, VA, USA
| | - Anutosh Ganguly
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Tamalika Paul
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
| | - Manali Powar
- Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Roanoke, VA, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, USA
- Institute for Critical and Applied Science Center for Engineered Health, Virginia Tech, Blacksburg, VA, USA
| | - Clifford S. Cho
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Research Service, Ann Arbor VA Healthcare, Ann Arbor, MI, USA
| | - Irving C. Allen
- Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Roanoke, VA, USA
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
- Institute for Critical and Applied Science Center for Engineered Health, Virginia Tech, Blacksburg, VA, USA
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
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Toydemir C, Hall S, Demirel E, Elmaci DN, Gol D, Vlaisavljevich E, Yuksel Durmaz Y. Bioconjugated β-Cyclodextrin-Perfluorohexane Nanocone Clusters as Functional Nanoparticles for Nanoparticle-Mediated Histotripsy. Biomacromolecules 2022; 23:5297-5311. [PMID: 36418020 DOI: 10.1021/acs.biomac.2c01110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nanocone clusters (NCCs) are new-generation agents of nanoparticle-mediated histotripsy (NMH) recently developed to address the limitations of previously designed nanodroplets (NDs). NCCs can be obtained by simply mixing FDA-approved cyclodextrins (CD) and suitable perfluorocarbons (PFCs), which result in smaller size aggregates, detectable PFC amount, and more stable long-term storage since the obtained powder can be stored and redispersed as needed. Previous experimental and computational studies showed that NCCs consist of an organization of inclusion complexes of CD and PFC around free PFC droplets, and their aggregate behavior depends on the localization of PFC in the cavity and the water solubility of CD derivatives. It has been shown that β-cyclodextrin (βCD) and perfluorohexane (PFH) are ideal candidates for NCCs that can be isolated as a powder with high PFC content among various CD and PFC derivatives. This study focuses on the further development of the selected NCC composition to enhance the potential of NMH therapy while also enabling more detailed future experiments in vitro and in vivo. It is aimed to show the bioconjugation potential of NCCs through the example of the most commonly used functionalization methods such as targeting, PEGylation, and fluorescent labeling. For this purpose, βCD as a building block was monofunctionalized with groups such as azide, alkyne, and amine groups that allow for effective coupling reactions such as the "click" reaction and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) coupling. These monofunctional βCDs were used as building blocks of NCCs in the presence of PFH to obtain functional NCCs as precursors of bioconjugation. EPPT1 as a synthetic peptide specific to uMUC1 and folic acid (FA) as the most commonly used targeting agent along with PEGylation were successfully shown as bioconjugation examples. Lastly, fluorescently labeled NCCs were obtained via fluorescein isothiocyanate (FITC) and alkyne functional NCC reaction through propargyl amine and isothiocyanate group reaction. The obtained bioconjugates were tested in vitro to validate the conjugation, and the ability to lower the histotripsy cavitation threshold, which is necessary for NMH, was demonstrated for all bioconjugates. Overall, the results showed that all obtained bioconjugates successfully lowered the cavitation threshold pressure while also fulfilling the desired bioconjugation metrics to serve as improved tools to enhance NMH as a targeted noninvasive ablation method.
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Affiliation(s)
| | - Sarah Hall
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia24061, United States
| | | | | | | | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia24061, United States
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43
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Rawnaque FS, Simon JC. The effects of elastic modulus and impurities on bubble nuclei available for acoustic cavitation in polyacrylamide hydrogels. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 152:3502. [PMID: 36586847 DOI: 10.1121/10.0016445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
Safety of biomedical ultrasound largely depends on controlling cavitation bubbles in vivo, yet bubble nuclei in biological tissues remain unexplored compared to water. This study evaluates the effects of elastic modulus (E) and impurities on bubble nuclei available for cavitation in tissue-mimicking polyacrylamide (PA) hydrogels. A 1.5 MHz focused ultrasound transducer with f# = 0.7 was used to induce cavitation in 17.5%, 20%, and 22.5% v/v PA hydrogels using 10-ms pulses with pressures up to peak negative pressure (p-) = 35 MPa. Cavitation was monitored at 0.075 ms through high-speed photography at 40 000 fps. At p- = 29 MPa for all hydrogels, cavitation occurred at random locations within the -6 dB focal area [9.4 × 1.2 mm (p-)]. Increasing p- to 35 MPa increased bubble location consistency and caused shock scattering in the E = 282 MPa hydrogels; as the E increased to 300 MPa, bubble location consistency decreased (p = 0.045). Adding calcium phosphate or cholesterol at 0.25% w/v or bovine serum albumin at 5% or 10% w/v in separate 17.5% PA as impurities decreased the cavitation threshold from p- = 13.2 MPa for unaltered PA to p- = 11.6 MPa, p- = 7.3 MPa, p- = 9.7 MPa, and p- = 7.5 MPa, respectively. These results suggest that both E and impurities affect the bubble nuclei available for cavitation in tissue-mimicking hydrogels.
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Affiliation(s)
- Ferdousi Sabera Rawnaque
- Graduate Program in Acoustics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Julianna C Simon
- Graduate Program in Acoustics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Development of an ultrasound guided focused ultrasound system for 3D volumetric low energy nanodroplet-mediated histotripsy. Sci Rep 2022; 12:20664. [PMID: 36450815 PMCID: PMC9712369 DOI: 10.1038/s41598-022-25129-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
Low pressure histotripsy is likely to facilitate current treatments that require extremely high pressures. An ultrasound guided focused ultrasound system was designed to accommodate a rotating imaging transducer within a low frequency therapeutic transducer that operates at a center frequency of 105 kHz. The implementation of this integrated system provides real-time therapeutic and volumetric imaging functions, that are used here for low-cost, low-energy 3D volumetric ultrasound histotripsy using nanodroplets. A two-step approach for low pressure histotripsy is implemented with this dual-array. Vaporization of nanodroplets into gaseous microbubbles was performed via the 1D rotating imaging probe. The therapeutic transducer is then used to detonate the vaporized nanodroplets and trigger potent mechanical effects in the surrounding tissue. Rotating the imaging transducer creates a circular vaporized nanodroplet shape which generates a round lesion upon detonation. This contrasts with the elongated lesion formed when using a standard 1D imaging transducer for nanodroplet activation. Optimization experiments show that maximal nanodroplet activation can be achieved with a 2-cycle excitation pulse at a center frequency of 3.5 MHz, and a peak negative pressure of 3.4 MPa (a mechanical index of 1.84). Vaporized nanodroplet detonation was achieved by applying a low frequency treatment at a center frequency of 105 kHz and mechanical index of 0.9. In ex-vivo samples, the rotated nanodroplet activation method yielded the largest lesion area, with a mean of 4.7 ± 0.5 mm2, and a rounded shape. In comparison, standard fixed transducer nanodroplet activation resulted in an average lesion area of 2.6 ± 0.4 mm2, and an elongated shape. This hybrid system enables to achieve volumetric low energy histotripsy, and thus facilitates the creation of precise, large-volume mechanical lesions in tissues, while reducing the pressure threshold required for standard histotripsy by over an order of magnitude.
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Bhargava A, Huang S, McPherson DD, Bader KB. Assessment of bubble activity generated by histotripsy combined with echogenic liposomes. Phys Med Biol 2022; 67:215015. [PMID: 36220055 DOI: 10.1088/1361-6560/ac994f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 10/11/2022] [Indexed: 11/05/2022]
Abstract
Objective.Histotripsy is a form of focused ultrasound therapy that uses the mechanical activity of bubbles to ablate tissue. While histotripsy alone degrades the cellular content of tissue, recent studies have demonstrated it effectively disrupts the extracellular structure of pathologic conditions such as venous thrombosis when combined with a thrombolytic drug. Rather than relying on standard administration methods, associating thrombolytic drugs with an ultrasound-triggered echogenic liposome vesicle will enable targeted, systemic drug delivery. To date, histotripsy has primarily relied on nano-nuclei inherent to the medium for bubble cloud generation, and microbubbles associated with echogenic liposomes may alter the histotripsy bubble dynamics. The objective of this work was to investigate the interaction of histotripsy pulse with echogenic liposomes.Approach.Bubble clouds were generated using a focused source in anin vitromodel of venous flow. Acoustic emissions generated during the insonation were passively acquired to assess the mechanical activity of the bubble cloud. High frame rate, pulse inversion imaging was used to track the change in echogenicity of the liposomes following histotripsy exposure.Main results.For peak negative pressures less than 20 MPa, acoustic emissions indicative of stable and inertial bubble activity were observed. As the peak negative pressure of the histotripsy excitation increased, harmonics of the excitation were observed in OFP t-ELIP solutions and plasma alone. Additional observations with high frame rate imaging indicated a transition of bubble behavior as the pulse pressure transitioned to shock wave formation.Significance.These observations suggest that a complex interaction between histotripsy pulses and echogenic liposomes that may be exploited for combination treatment approaches.
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Affiliation(s)
- Aarushi Bhargava
- Department of Radiology, University of Chicago, Chicago, IL, United States of America
| | - Shaoling Huang
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Texas Health Sciences Center-Houston, Houston, TX, United States of America
| | - David D McPherson
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Texas Health Sciences Center-Houston, Houston, TX, United States of America
| | - Kenneth B Bader
- Department of Radiology, University of Chicago, Chicago, IL, United States of America
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Sarkar K. Rayleigh limit extended: Scattering from a fluid sphere. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 152:R7. [PMID: 36319256 DOI: 10.1121/10.0014345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/17/2022] [Indexed: 06/16/2023]
Abstract
The Reflections series takes a look back on historical articles from The Journal of the Acoustical Society of America that have had a significant impact on the science and practice of acoustics.
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Affiliation(s)
- Kausik Sarkar
- Mechanical and Aerospace Engineering, The George Washington University, Washington, District of Columbia 20052, USA
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47
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Bismuth M, Katz S, Mano T, Aronovich R, Hershkovitz D, Exner AA, Ilovitsh T. Low frequency nanobubble-enhanced ultrasound mechanotherapy for noninvasive cancer surgery. NANOSCALE 2022; 14:13614-13627. [PMID: 36070492 DOI: 10.1039/d2nr01367c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Scaling down the size of microbubble contrast agents to the nanometer level holds the promise for noninvasive cancer therapy. However, the small size of nanobubbles limits the obtained bioeffects as a result of ultrasound cavitation, when operating near the nanobubble resonance frequency. Here we show that coupled with low energy insonation at a frequency of 80 kHz, well below the resonance frequency of these agents, nanobubbles serve as noninvasive therapeutic warheads that trigger potent mechanical effects in tumors following a systemic injection. We demonstrate these capabilities in tissue mimicking phantoms, where a comparison of the acoustic response of micro- and nano-bubbles after insonation at a frequency of 250 or 80 kHz revealed that higher pressures were needed to implode the nanobubbles compared to microbubbles. Complete nanobubble destruction was achieved at a mechanical index of 2.6 for the 250 kHz insonation vs. 1.2 for the 80 kHz frequency. Thus, the 80 kHz insonation complies with safety regulations that recommend operation below a mechanical index of 1.9. In vitro in breast cancer tumor cells, the cell viability was reduced to 17.3 ± 1.7% of live cells. In vivo, in a breast cancer tumor mouse model, nanobubble tumor distribution and accumulation were evaluated by high frequency ultrasound imaging. Finally, nanobubble-mediated low frequency insonation of breast cancer tumors resulted in effective mechanical tumor ablation and tumor tissue fractionation. This approach provides a unique theranostic platform for safe, noninvasive and low energy tumor mechanotherapy.
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Affiliation(s)
- Mike Bismuth
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Sharon Katz
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tamar Mano
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Ramona Aronovich
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Dov Hershkovitz
- Department of Pathology, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 6997800, Israel
| | - Agata A Exner
- Departments of Radiology and Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Tali Ilovitsh
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
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Simon A, Robinson F, Anzivino A, Boyer M, Hendricks-Wenger A, Guilliams D, Casey J, Grider D, Valea F, Vlaisavljevich E. Histotripsy for the Treatment of Uterine Leiomyomas: A Feasibility Study in Ex Vivo Uterine Fibroids. ULTRASOUND IN MEDICINE & BIOLOGY 2022; 48:1652-1662. [PMID: 35641394 DOI: 10.1016/j.ultrasmedbio.2022.04.214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 04/01/2022] [Accepted: 04/22/2022] [Indexed: 06/15/2023]
Abstract
Uterine fibroids (leiomyomas), the most common benign tumors in women of reproductive age, are a frequent cause of abnormal vaginal bleeding and other reproductive complaints among women. This study investigates the feasibility of using histotripsy, a non-invasive, non-thermal focused ultrasound ablation method, to ablate uterine fibroids. Human fibroid samples (n = 16) were harvested after hysterectomy or myomectomy procedures at Carilion Memorial Hospital. Histotripsy was applied to ex vivo fibroids in two sets of experiments using a 700-kHz clinical transducer to apply multicycle histotripsy pulses and a prototype 500-kHz transducer to apply single-cycle histotripsy pulses. Ultrasound imaging was used for real-time treatment monitoring, and post-treatment ablation was quantified histologically using hematoxylin and eosin and Masson trichrome stains. Results revealed that multicycle histotripsy generated diffuse cavitation in targeted fibroids, with minimal cellular ablative changes after treatment with 2000 pulses/point. Single-cycle pulsing generated well-confined bubble clouds with evidence of early coagulative necrosis on histological assessment in samples treated with 2000 pulses/point, near-complete ablation in samples treated with 4000 pulses/point and complete tissue destruction in samples treated with 10,000 pulses/point. This study illustrates that histotripsy is capable of fibroid ablation under certain pulsing parameters and warrants further investigation as an improved non-invasive ablation method for the treatment of leiomyomas.
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Affiliation(s)
- Alex Simon
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, Virginia, USA
| | - Faith Robinson
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA
| | - Anthony Anzivino
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA
| | - Maggie Boyer
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia, USA
| | - Alissa Hendricks-Wenger
- Department of Translational Biology, Medicine and Health, Virginia Tech, Blacksburg, VA, USA
| | - Danielle Guilliams
- Department of Research and Development, Carilion Clinic, Roanoke, Virginia, USA
| | - James Casey
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA; Department of Obstetrics and Gynecology, Carilion Clinic Gynecological Oncology, Roanoke, Virginia, USA
| | - Douglas Grider
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA; Dominion Pathology Associates, Roanoke, Virginia, USA
| | - Fidel Valea
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA; Department of Obstetrics and Gynecology, Carilion Clinic Gynecological Oncology, Roanoke, Virginia, USA
| | - Eli Vlaisavljevich
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, Virginia, USA.
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de Andrade MO, Haqshenas R, Pahk KJ, Saffari N. Mechanisms of nuclei growth in ultrasound bubble nucleation. ULTRASONICS SONOCHEMISTRY 2022; 88:106091. [PMID: 35839705 PMCID: PMC9287806 DOI: 10.1016/j.ultsonch.2022.106091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/20/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
This paper interrogates the intersections between bubble dynamics and classical nucleation theory (CNT) towards constructing a model that describes intermediary nucleation events between the extrema of cavitation and boiling. We employ Zeldovich's hydrodynamic approach to obtain a description of bubble nuclei that grow simultaneously via hydrodynamic excitation by the acoustic field and vapour transport. By quantifying the relative dominance of both mechanisms, it is then possible to discern the extent to which viscosity, inertia, surface tension and vapour transport shape the growth of bubble nuclei through non-dimensional numbers that naturally arise within the theory. The first non-dimensional number Φ12/Φ2 is analogous to the Laplace number, representing the balance between surface tension and inertial constraints to viscous effects. The second non-dimensional number δ represents how enthalpy transport into the bubble can reduce nucleation rates by cooling the surrounding liquid. This formulation adds to the current understanding of ultrasound bubble nucleation by accounting for bubble dynamics during nucleation, quantifying the physical distinctions between "boiling" and "cavitation" bubbles through non-dimensional parameters, and outlining the characteristic timescales of nucleation according to the growth mechanism of bubbles throughout the histotripsy temperature range. We observed in our simulations that viscous effects control the process of ultrasound nucleation in water-like media throughout the 0-120 °C temperature range, although this dominance decreases with increasing temperatures. Enthalpy transport was found to reduce nucleation rates for increasing temperatures. This effect becomes significant at temperatures above 30 °C and favours the creation of fewer nuclei that are larger in size. Conversely, negligible enthalpy transport at lower temperatures can enable the nucleation of dense clusters of small nuclei, such as cavitation clouds. We find that nuclei growth as modelled by the Rayleigh-Plesset equation occurs over shorter timescales than as modelled by vapour-dominated growth. This suggests that the first stage of bubble nuclei growth is hydrodynamic, and vapour transport effects can only be observed over longer timescales. Finally, we propose that this framework can be used for comparison between different experiments in bubble nucleation, towards standardisation and dosimetry of protocols.
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Affiliation(s)
| | - Reza Haqshenas
- UCL Mechanical Engineering, University College London, London, United Kingdom
| | - Ki Joo Pahk
- Department of Biomedical Engineering, Kyung Hee University, Yongin, Republic of Korea
| | - Nader Saffari
- UCL Mechanical Engineering, University College London, London, United Kingdom
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50
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Yeats E, Gupta D, Xu Z, Hall TL. Effects of phase aberration on transabdominal focusing for a large aperture, low f-number histotripsy transducer. Phys Med Biol 2022; 67:10.1088/1361-6560/ac7d90. [PMID: 35772383 PMCID: PMC9396534 DOI: 10.1088/1361-6560/ac7d90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 06/30/2022] [Indexed: 11/12/2022]
Abstract
Objective. Soft tissue phase aberration may be particularly severe for histotripsy due to large aperture and lowf-number transducer geometries. This study investigated how phase aberration from human abdominal tissue affects focusing of a large, strongly curved histotripsy transducer.Approach.A computational model (k-Wave) was experimentally validated withex vivoporcine abdominal tissue and used to simulate focusing a histotripsy transducer (radius: 14.2 cm,f-number: 0.62, central frequencyfc: 750 kHz) through the human abdomen. Abdominal computed tomography images from 10 human subjects were segmented to create three-dimensional acoustic property maps. Simulations were performed focusing at 3 target locations in the liver of each subject with ideal phase correction, without phase correction, and after separately matching the sound speed of water and fat to non-fat soft tissue.Main results.Experimental validation in porcine abdominal tissue showed that simulated and measured arrival time differences agreed well (average error, ∼0.10 acoustic cycles atfc). In simulations with human tissue, aberration created arrival time differences of 0.65μs (∼0.5 cycles) at the target and shifted the focus from the target by 6.8 mm (6.4 mm pre-focally along depth direction), on average. Ideal phase correction increased maximum pressure amplitude by 95%, on average. Matching the sound speed of water and fat to non-fat soft tissue decreased the average pre-focal shift by 3.6 and 0.5 mm and increased pressure amplitude by 2% and 69%, respectively.Significance.Soft tissue phase aberration of large aperture, lowf-number histotripsy transducers is substantial despite low therapeutic frequencies. Phase correction could potentially recover substantial pressure amplitude for transabdominal histotripsy. Additionally, different heterogeneity sources distinctly affect focusing quality. The water path strongly affects the focal shift, while irregular tissue boundaries (e.g. fat) dominate pressure loss.
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Affiliation(s)
- Ellen Yeats
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States of America
| | - Dinank Gupta
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States of America
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States of America
| | - Timothy L Hall
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States of America
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