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Merdalimova A, Barmin R, Vorobev V, Aleksandrov A, Terentyeva D, Estifeeva T, Chernyshev V, German S, Maslov O, Skibina Y, Rudakovskaya P, Gorin D. Two-in-one sensor of refractive index and Raman scattering using hollow-core microstructured optical waveguides for colloid characterization. Colloids Surf B Biointerfaces 2024; 234:113705. [PMID: 38194837 DOI: 10.1016/j.colsurfb.2023.113705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/01/2023] [Accepted: 12/07/2023] [Indexed: 01/11/2024]
Abstract
Hollow-core microstructured optical waveguides (HC-MOW) have recently emerged in sensing technologies, including the gas and liquid detection for industrial as well as clinical applications. Antiresonant HC-MOW provide capabilities for applications in refractive index (RI) sensing, while the long optical path for analyte-light interaction in HC-MOW leads to increased sensitivity of sensor based on Raman scattering signal measurements. In this study, we developed a two-in-one sensor device using HC-MOW for RI and Raman scattering detection. The performance of the sensor was evaluated by characterizing protein-copolymer multicomponent colloids, specifically, bovine serum albumin (BSA) and poly(N - vinyl-2 -pyrrolidone-co-acrylic acid) P(VP-AA) nano-sized complexes and microbubbles of the corresponding shell. Monocomponent solutions showed linear dependencies of RI and characteristic Raman peak intensities on mass concentration. Multicomponent Raman sensing of BSA@P(VP-AA) complexes and microbubbles revealed that changes in P(VP-AA) characteristic peak intensities can describe interactions between components needed to produce colloid systems. RI sensing of multicomponent colloids demonstrated linear dependence on total mass concentrations for BSA@P(VP-AA) complexes, while corresponding BSA@P(VP-AA) microbubbles can be detected with concentrations as high as 4.0 × 108 MB/mL. Therefore, the developed two-in-one sensor of RI and Raman scattering can be used the robust characterization of albumin-based colloids designed for therapeutic and diagnostic needs.
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Affiliation(s)
- Anastasiia Merdalimova
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia; Laboratory of Photonic Gas Sensors, University of Science and Technology MISIS, Moscow 119049, Russia.
| | - Roman Barmin
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia.
| | - Viktor Vorobev
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Artem Aleksandrov
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia; Faculty of Materials Science, Lomonosov Moscow State University, Moscow 119991, Russia; National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov, Moscow 117997, Russia
| | - Daria Terentyeva
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Tatiana Estifeeva
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Vasiliy Chernyshev
- National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov, Moscow 117997, Russia
| | - Sergey German
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Oleg Maslov
- Department of Nanomaterials and Nanotechnology, Dmitry Mendeleev University of Chemical Technology of Russia, Moscow 125047, Russia
| | - Yulia Skibina
- SPE LLC Nanostructured Glass Technology, Saratov 410033, Russia
| | - Polina Rudakovskaya
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Dmitry Gorin
- Center for Photonic Science and Engineering, Skolkovo Institute of Science and Technology, Moscow 121205, Russia.
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McGrath S, Shen YJ, Aragaki M, Motooka Y, Koga T, Gregor A, Bernards N, Cherin E, Demore CEM, Yasufuku K, Matsuura N. Imaging Microbubbles With Contrast-Enhanced Endobronchial Ultrasound. Ultrasound Med Biol 2024; 50:28-38. [PMID: 37813701 DOI: 10.1016/j.ultrasmedbio.2023.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 08/02/2023] [Accepted: 08/28/2023] [Indexed: 10/11/2023]
Abstract
OBJECTIVE Endobronchial ultrasound (EBUS) is commonly used to guide transbronchial needle biopsies for the staging of lymph nodes in non-small cell lung cancer patients. Although contrast-enhanced ultrasound (CEUS) and microbubbles (MBs) can improve the diagnostic accuracy in tumors, the ability of contrast-enhanced EBUS (CE-EBUS) to image MBs has not yet been comprehensively evaluated. In this study, we assessed the ability of a CE-EBUS system (Olympus EU-ME2 PREMIER and BF-UC180F bronchoscope) to detect laboratory-synthesized MBs in comparison to clinical (Toshiba Aplio SSA-790A) and pre-clinical (VisualSonics Vevo 2100) CEUS systems in vitro and in vivo, respectively. METHODS Agar flow phantoms and reference tissue were used to assess CE-EBUS MB imaging in vitro, and A549 tumor-bearing athymic nude and AE17-OVA tumor-bearing C57BL/6 mice were used to assess MB detectability and perfusion in vivo, respectively. RESULTS Results revealed that despite the lower sensitivity of CE-EBUS to MB concentration in comparison to clinical CEUS, CE-EBUS yielded a similar contrast-to-tissue ratio (CTR) in vitro of 28.9 ± 4.5 dB for CE-EBUS, compared with 29.7 ± 2.6 dB for clinical CEUS (p < 0.05). In vivo, CE-EBUS generated a perfusion curve highly correlated with that obtained with the pre-clinical CEUS system (Pearson correlation coefficient = 0.927, p < 0.05). Moreover, CE-EBUS yielded a CTR 2.7 times higher than that obtained with the pre-clinical ultrasound system. CONCLUSION These findings together suggest that CE-EBUS can perform contrast imaging comparable to that produced by commercial pre-clinical and clinical ultrasound systems, with potential for clinical characterization of mediastinal lymph nodes in lung cancer patients.
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Affiliation(s)
- Sean McGrath
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Yu-Jack Shen
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Masato Aragaki
- Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Yamato Motooka
- Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Takamasa Koga
- Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Alexander Gregor
- Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Nicholas Bernards
- Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Emmanuel Cherin
- Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Christine E M Demore
- Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada; Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Kazuhiro Yasufuku
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Division of Thoracic Surgery, Toronto General Hospital, University Health Network, Toronto, ON, Canada
| | - Naomi Matsuura
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Department of Materials Science & Engineering, University of Toronto, Toronto, ON, Canada; Department of Medical Imaging, University of Toronto, Toronto, ON, Canada.
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Monzeglio O, Melissa VM, Rodolfi S, Valentini E, Carriero A. Exploring the potential of contrast agents in breast cancer echography: current state and future directions. J Ultrasound 2023; 26:749-756. [PMID: 37566194 PMCID: PMC10632334 DOI: 10.1007/s40477-023-00809-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 07/08/2023] [Indexed: 08/12/2023] Open
Abstract
Breast cancer stands as the most frequent malignancy and leading cause of death among women. Early and accurate detection of this pathology represents a crucial factor in enhancing both incidence and mortality rates. Ultrasound (US) examination has been extensively adopted in clinical practice due to its non-invasiveness, affordability, ease of implementation, and wide accessibility, thus representing a valuable first-line diagnostic tool for the study of the mammary gland. In this scenario, recent developments in nanomedicine are paving the way for new interpretations and applications of US diagnostics, which are becoming increasingly personalized based on the molecular phenotype of each tumor, allowing for more precise and accurate evaluations. This review highlights the current state-of-the-art of US diagnosis of breast cancer, as well as the recent advancements related to the application of US contrast agents to the field of molecular diagnostics, still under preclinical study.
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Affiliation(s)
- Oriana Monzeglio
- Department of Diagnosis and Treatment Services, Radiodiagnostics and Interventional Radiology, AOU Maggiore Della Carità, Corso Mazzini 18, 28100, Novara, Italy.
| | - Vittoria Maria Melissa
- Department of Diagnosis and Treatment Services, Radiodiagnostics and Interventional Radiology, AOU Maggiore Della Carità, Corso Mazzini 18, 28100, Novara, Italy
| | - Sara Rodolfi
- Department of Diagnosis and Treatment Services, Radiodiagnostics and Interventional Radiology, AOU Maggiore Della Carità, Corso Mazzini 18, 28100, Novara, Italy
| | - Eleonora Valentini
- Department of Diagnosis and Treatment Services, Radiodiagnostics and Interventional Radiology, AOU Maggiore Della Carità, Corso Mazzini 18, 28100, Novara, Italy
| | - Alessandro Carriero
- Department of Translation Medicine, University of Eastern Piemonte UPO, Via Solaroli 17, 28100, Novara, Italy
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Hampson R, Senior R, Ring L, Robinson S, Augustine DX, Becher H, Anderson N, Willis J, Chandrasekaran B, Kardos A, Siva A, Leeson P, Rana BS, Chahal N, Oxborough D. Contrast echocardiography: a practical guideline from the British Society of Echocardiography. Echo Res Pract 2023; 10:23. [PMID: 37964335 PMCID: PMC10648732 DOI: 10.1186/s44156-023-00034-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 10/11/2023] [Indexed: 11/16/2023] Open
Abstract
Ultrasound contrast agents (UCAs) have a well-established role in clinical cardiology. Contrast echocardiography has evolved into a routine technique through the establishment of contrast protocols, an excellent safety profile, and clinical guidelines which highlight the incremental prognostic utility of contrast enhanced echocardiography. This document aims to provide practical guidance on the safe and effective use of contrast; reviews the role of individual staff groups; and training requirements to facilitate its routine use in the echocardiography laboratory.
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Affiliation(s)
| | - Roxy Senior
- London North West University Healthcare NHS Trust, London, UK.
- Royal Brompton Hospital and Imperial College, London, UK.
| | - Liam Ring
- West Suffolk Hospital NHS Foundation Trust, Bury St Edmunds, UK
| | | | - Daniel X Augustine
- Royal United Hospitals Bath NHS Foundation Trust, Bath, UK
- Department for, Health University of Bath, Bath, UK
| | - Harald Becher
- Alberta Heart Institute, University of Alberta Hospital, Edmonton, Canada
| | - Natasha Anderson
- Warrington and Halton Teaching Hospital NHS Foundation Trust, Warrington, UK
| | - James Willis
- Royal United Hospitals Bath NHS Foundation Trust, Bath, UK
| | | | - Attila Kardos
- Translational Cardiovascular Research Group, Department of Cardiology, Milton Keynes University Hospital, Milton Keynes, UK
- Faculty of Medicine and Health Sciences, University of Buckingham, Buckingham, UK
| | | | - Paul Leeson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Navtej Chahal
- London North West University Healthcare NHS Trust, London, UK
| | - David Oxborough
- Liverpool Centre for Cardiovascular Science, Liverpool John Moores University, Liverpool, UK
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van Elburg B, Deprez J, van den Broek M, De Smedt SC, Versluis M, Lajoinie G, Lentacker I, Segers T. Dependence of sonoporation efficiency on microbubble size: An in vitro monodisperse microbubble study. J Control Release 2023; 363:747-755. [PMID: 37778466 DOI: 10.1016/j.jconrel.2023.09.047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/24/2023] [Accepted: 09/26/2023] [Indexed: 10/03/2023]
Abstract
Sonoporation is the process where intracellular drug delivery is facilitated by ultrasound-driven microbubble oscillations. Several mechanisms have been proposed to relate microbubble dynamics to sonoporation including shear and normal stress. The present work aims to gain insight into the role of microbubble size on sonoporation and thereby into the relevant mechanism(s) of sonoporation. To this end, we measured the sonoporation efficiency while varying microbubble size using monodisperse microbubble suspensions. Sonoporation experiments were performed in vitro on cell monolayers using a single ultrasound pulse with a fixed frequency of 1 MHz while the acoustic pressure amplitude and pulse length were varied at 250, 500, and 750 kPa, and 10, 100, and 1000 cycles, respectively. Sonoporation efficiency was quantified using flow cytometry by measuring the FITC-dextran (4 kDa and 2 MDa) fluorescence intensity in 10,000 cells per experiment to average out inherent variations in the bioresponse. Using ultra-high-speed imaging at 10 million frames per second, we demonstrate that the bubble oscillation amplitude is nearly independent of the equilibrium bubble radius at acoustic pressure amplitudes that induce sonoporation (≥ 500 kPa). However, we show that sonoporation efficiency is strongly dependent on the equilibrium bubble size and that under all explored driving conditions most efficiently induced by bubbles with a radius of 4.7 μm. Polydisperse microbubbles with a typical ultrasound contrast agent size distribution perform almost an order of magnitude lower in terms of sonoporation efficiency than the 4.7-μm bubbles. We elucidate that for our system shear stress is highly unlikely the mechanism of action. By contrast, we show that sonoporation efficiency correlates well with an estimate of the bubble-induced normal stress.
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Affiliation(s)
- Benjamin van Elburg
- Physics of Fluids Group and Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands
| | - Joke Deprez
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Ghent University, Ghent, Belgium
| | - Martin van den Broek
- BIOS / Lab on a Chip Group, Max-Planck Center Twente for Complex Fluid Dynamics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, Netherlands
| | - Stefaan C De Smedt
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Michel Versluis
- Physics of Fluids Group and Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands
| | - Guillaume Lajoinie
- Physics of Fluids Group and Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands
| | - Ine Lentacker
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Tim Segers
- BIOS / Lab on a Chip Group, Max-Planck Center Twente for Complex Fluid Dynamics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, Netherlands.
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Juang EK, De Koninck LH, Vuong KS, Gnanaskandan A, Hsiao CT, Averkiou MA. Controlled Hyperthermia With High-Intensity Focused Ultrasound and Ultrasound Contrast Agent Microbubbles in Porcine Liver. Ultrasound Med Biol 2023; 49:1852-1860. [PMID: 37246049 PMCID: PMC10330369 DOI: 10.1016/j.ultrasmedbio.2023.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 04/07/2023] [Accepted: 04/25/2023] [Indexed: 05/30/2023]
Abstract
OBJECTIVE The objective of this work was to study microbubble-enhanced temperature elevation with high-intensity focused ultrasound (HIFU) at different acoustic pressures and under image guidance. The microbubbles were administered with either local or vascular injections (that mimic systemic injections) in perfused and non-perfused ex vivo porcine liver under ultrasound image guidance. METHODS Porcine liver was insonified for 30 s with a single-element HIFU transducer (0.9 MHz, 0.413 ms, 82% duty cycle, focal pressures of 0.6-3.5 MPa). Contrast microbubbles were injected either locally or through the vasculature. A needle thermocouple at the focus measured temperature elevation. Diagnostic ultrasound (Philips iU22, C5-1 probe) guided placement of the thermocouple and delivery of microbubbles and monitored the procedure in real time. RESULTS At lower acoustic pressures (0.6 and 1.2 MPa) in non-perfused liver, inertial cavitation of the injected microbubbles led to greater temperatures at the focus compared with HIFU-only treatments. At higher pressures (2.4 and 3.5 MPa) native inertial cavitation in the tissue (without injecting microbubbles) resulted in temperature elevations similar to those after injecting microbubbles. The heated area was larger when using microbubbles at all pressures. In the presence of perfusion, only local injections provided a sufficiently high concentration of microbubbles necessary for significant temperature enhancement. CONCLUSION Local injections of microbubbles provide a higher concentration of microbubbles in a smaller area, avoiding acoustic shadowing, and can lead to higher temperature elevation at lower pressures and increase the size of the heated area at all pressures.
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Affiliation(s)
- Eric K Juang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Lance H De Koninck
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Kaleb S Vuong
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Aswin Gnanaskandan
- Department of Mechanical and Materials Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
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Azami RH, Forsberg F, Eisenbrey JR, Sarkar K. Ambient Pressure Sensitivity of the Subharmonic Response of Coated Microbubbles: Effects of Acoustic Excitation Parameters. Ultrasound Med Biol 2023; 49:1550-1560. [PMID: 37100673 DOI: 10.1016/j.ultrasmedbio.2023.02.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/20/2023] [Accepted: 02/27/2023] [Indexed: 05/17/2023]
Abstract
OBJECTIVE The sensitivity of the acoustic response of microbubbles, specifically a strong correlation between their subharmonic response and the ambient pressure, has motivated development of a non-invasive subharmonic-aided pressure estimation (SHAPE) method. However, this correlation has previously been found to vary depending on the microbubble type, the acoustic excitation and the hydrostatic pressure range. In this study, the ambient pressure sensitivity of microbubble response was investigated. METHODS The fundamental, subharmonic, second harmonic and ultraharmonic responses from an in-house lipid-coated microbubble were measured for excitations with peak negative pressures (PNPs) of 50-700 kPa and frequencies of 2, 3 and 4 MHz in the ambient overpressure range 0-25 kPa (0-187 mmHg) in an in vitro setup. RESULTS The subharmonic response typically has three stages-occurrence, growth and saturation-with increasing excitation PNP. We find distinct decreasing and increasing variations of the subharmonic signal with overpressure that are closely related to the threshold of subharmonic generation in a lipid-shelled microbubble. Above the excitation threshold, that is, in the growth-saturation phase, subharmonic signals decreased linearly with slopes as high as -0.56 dB/kPa with ambient pressure increase; below the threshold excitation (at atmospheric pressure), increasing overpressure triggers subharmonic generation, indicating a lowering of subharmonic threshold, and therefore leads to an increase in subharmonic with overpressure, the maximum enhancement being ∼11 dB for 15 kPa overpressure at 2 MHz and 100 kPa PNP. CONCLUSION This study indicates the possible development of novel and improved SHAPE methodologies.
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Affiliation(s)
- Roozbeh H Azami
- Department of Mechanical and Aerospace Engineering, George Washington University, Washington, DC, USA
| | - Flemming Forsberg
- Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - John R Eisenbrey
- Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Kausik Sarkar
- Department of Mechanical and Aerospace Engineering, George Washington University, Washington, DC, USA.
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Haram M, Snipstad S, Berg S, Mjønes P, Rønne E, Lage J, Mühlenpfordt M, Davies CDL. Ultrasound and Microbubbles Increase the Uptake of Platinum in Murine Orthotopic Pancreatic Tumors. Ultrasound Med Biol 2023; 49:1275-1287. [PMID: 36842903 DOI: 10.1016/j.ultrasmedbio.2023.01.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/21/2022] [Accepted: 01/19/2023] [Indexed: 05/11/2023]
Abstract
OBJECTIVE Currently available cytotoxic treatments have limited effect on pancreatic ductal adenocarcinoma (PDAC) because desmoplastic stroma limits drug delivery. Efforts have been made to overcome these barriers by drug targeting the tumor microenvironment. Results so far are promising, but without clinical impact. Our aim was to investigate whether ultrasound and microbubbles could improve the uptake and therapeutic response of conventional chemotherapy. METHODS Orthotopic pancreatic tumors growing in mice were treated with commercially available FOLFIRINOX (fluorouracil, irinotecan, oxaliplatin and calcium folinate) and SonoVue microbubbles combined with focused ultrasound. Tumor uptake of platinum (Pt) was measured by inductively coupled plasma mass spectroscopy (ICP-MS), and tumor volumes were measured by ultrasound imaging. DISCUSSION Uptake of Pt, the active ingredient of oxaliplatin, was significantly increased after ultrasound treatment of orthotopic PDAC tumors. Multiple injections with FOLFIRONOX increased the amount of Pt in tumors. However, the enhanced accumulation did not improve therapeutic response. Increased uptake of Pt confirms that ultrasound and microbubbles have potential in clinical practice with existing drugs. CONCLUSION The lack of therapeutic response, despite increased uptake in tumor tissue, emphasizes the importance of studying how to overcome stromal barriers.
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Affiliation(s)
- Margrete Haram
- Department of Radiology and Nuclear Medicine, St. Olav's Hospital-Trondheim University Hospital, Trondheim, Norway; Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Cancer Clinic, St. Olav's Hospital-Trondheim University Hospital, Trondheim, Norway.
| | - Sofie Snipstad
- Cancer Clinic, St. Olav's Hospital-Trondheim University Hospital, Trondheim, Norway; Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway; Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway
| | - Sigrid Berg
- Department of Health Research, SINTEF Digital, Trondheim, Norway
| | - Patricia Mjønes
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Department of Pathology, St. Olav's Hospital-Trondheim University Hospital, Trondheim, Norway
| | - Elin Rønne
- Department of Pathology, St. Olav's Hospital-Trondheim University Hospital, Trondheim, Norway
| | - Jessica Lage
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
| | - Melina Mühlenpfordt
- Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
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9
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Chen X, Chen X, Wang J, Yu FTH, Villanueva FS, Pacella JJ. Dynamic Behavior of Polymer Microbubbles During Long Ultrasound Tone-Burst Excitation and Its Application for Sonoreperfusion Therapy. Ultrasound Med Biol 2023; 49:996-1006. [PMID: 36697268 PMCID: PMC9974862 DOI: 10.1016/j.ultrasmedbio.2022.12.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
OBJECTIVE Ultrasound (US)-targeted microbubble (MB) cavitation (UTMC)-mediated therapies have been found to restore perfusion and enhance drug/gene delivery. Because of the potentially longer circulation time and relative ease of storage and reconstitution of polymer-shelled MBs compared with lipid MBs, we investigated the dynamic behavior of polymer microbubbles and their therapeutic potential for sonoreperfusion (SRP) therapy. METHODS The fate of polymer MBs during a single long tone-burst exposure (1 MHz, 5 ms) at various acoustic pressures and MB concentrations was recorded via high-speed microscopy and passive cavitation detection (PCD). SRP efficacy of the polymer MBs was investigated in an in vitro flow system and compared with that of lipid MBs. DISCUSSION Microscopy videos indicated that polymer MBs formed gas-filled clusters that continued to oscillate, fragment and form new gas-filled clusters during the single US burst. PCD confirmed continued acoustic activity throughout the 5-ms US excitation. SRP efficacy with polymer MBs increased with pulse duration and acoustic pressure similarly to that with lipid MBs but no significant differences were found between polymer and lipid MBs. CONCLUSION These data suggest that persistent cavitation activity from polymer MBs during long tone-burst US excitation confers excellent reperfusion efficacy.
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Affiliation(s)
- Xianghui Chen
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA; Department of Cardiology, First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xucai Chen
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Jianjun Wang
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Francois T H Yu
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Flordeliza S Villanueva
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - John J Pacella
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
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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. Ultrason Sonochem 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] [What about the content of this article? (0)] [Affiliation(s)] [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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11
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Pathour T, Chaudhary S, Sirsi SR, Fei B. Hemoglobin Microbubbles and the Prediction of Different Oxygen Levels Using RF Data and Deep Learning. Proc SPIE Int Soc Opt Eng 2023; 12470:124700G. [PMID: 38495411 PMCID: PMC10942652 DOI: 10.1117/12.2655121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Ultrasound contrast agents (UCA) are gas-encapsulated microspheres that oscillate volumetrically when exposed to an ultrasound field producing backscattered signals efficiently, which can be used for improved ultrasound imaging and drug delivery applications. We developed a novel oxygen-sensitive hemoglobin-shell microbubble designed to acoustically detect blood oxygen levels. We hypothesize that structural change in hemoglobin caused due to varying oxygen levels in the body can lead to mechanical changes in the shell of the UCA. This can produce detectable changes in the acoustic response that can be used for measuring oxygen levels in the body. In this study, we have shown that oxygenated hemoglobin microbubbles can be differentiated from deoxygenated hemoglobin microbubbles using a 1D convolutional neural network using radiofrequency (RF) data. We were able to classify RF data from oxygenated and deoxygenated hemoglobin microbubbles into the two classes with a testing accuracy of 90.15%. The results suggest that oxygen content in hemoglobin affects the acoustical response and may be used for determining oxygen levels and thus could open many applications, including evaluating hypoxic regions in tumors and the brain, among other blood-oxygen-level-dependent imaging applications.
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Affiliation(s)
- Teja Pathour
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
| | - Sugandha Chaudhary
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
| | - Shashank R. Sirsi
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
| | - Baowei Fei
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
- Department of Radiology. UT Southwestern Medical Center, Dallas, TX
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12
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Li H, Li X, Collado-Lara G, Lattwein KR, Mastik F, Beurskens R, van der Steen AFW, Verweij MD, de Jong N, Kooiman K. Coupling Two Ultra-high-Speed Cameras to Elucidate Ultrasound Contrast-Mediated Imaging and Therapy. Ultrasound Med Biol 2023; 49:388-397. [PMID: 36241587 DOI: 10.1016/j.ultrasmedbio.2022.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 08/26/2022] [Accepted: 08/31/2022] [Indexed: 06/16/2023]
Abstract
Ultrasound contrast-mediated medical imaging and therapy both rely on the dynamics of micron- and nanometer-sized ultrasound cavitation nuclei, such as phospholipid-coated microbubbles and phase-change droplets. Ultrasound cavitation nuclei respond non-linearly to ultrasound on a nanosecond time scale that necessitates the use of ultra-high-speed imaging to fully visualize these dynamics in detail. In this study, we developed an ultra-high-speed optical imaging system that can record up to 20 million frames per second (Mfps) by coupling two small-sized, commercially available, 10-Mfps cameras. The timing and reliability of the interleaved cameras needed to achieve 20 Mfps was validated using two synchronized light-emitting diode strobe lights. Once verified, ultrasound-activated microbubble responses were recorded and analyzed. A unique characteristic of this coupled system is its ability to be reconfigured to provide orthogonal observations at 10 Mfps. Acoustic droplet vaporization was imaged from two orthogonal views, by which the 3-D dynamics of the phase transition could be visualized. This optical imaging system provides the temporal resolution and experimental flexibility needed to further elucidate the dynamics of ultrasound cavitation nuclei to potentiate the clinical translation of ultrasound-mediated imaging and therapy developments.
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Affiliation(s)
- Hongchen Li
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands.
| | - Xiufeng Li
- Section of Medical Imaging, Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Gonzalo Collado-Lara
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Kirby R Lattwein
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Frits Mastik
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Robert Beurskens
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Antonius F W van der Steen
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands; Section of Medical Imaging, Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Martin D Verweij
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands; Section of Medical Imaging, Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Nico de Jong
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands; Section of Medical Imaging, Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Klazina Kooiman
- Department of Biomedical Engineering, Thoraxcenter, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
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13
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Wang J, Li Z, Pan M, Fiaz M, Hao Y, Yan Y, Sun L, Yan F. Ultrasound-mediated blood-brain barrier opening: An effective drug delivery system for theranostics of brain diseases. Adv Drug Deliv Rev 2022; 190:114539. [PMID: 36116720 DOI: 10.1016/j.addr.2022.114539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 09/04/2022] [Accepted: 09/11/2022] [Indexed: 01/24/2023]
Abstract
Blood-brain barrier (BBB) remains a significant obstacle to drug therapy for brain diseases. Focused ultrasound (FUS) combined with microbubbles (MBs) can locally and transiently open the BBB, providing a potential strategy for drug delivery across the BBB into the brain. Nowadays, taking advantage of this technology, many therapeutic agents, such as antibodies, growth factors, and nanomedicine formulations, are intensively investigated across the BBB into specific brain regions for the treatment of various brain diseases. Several preliminary clinical trials also have demonstrated its safety and good tolerance in patients. This review gives an overview of the basic mechanisms, ultrasound contrast agents, evaluation or monitoring methods, and medical applications of FUS-mediated BBB opening in glioblastoma, Alzheimer's disease, and Parkinson's disease.
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Affiliation(s)
- Jieqiong Wang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai 201206, China
| | - Zhenzhou Li
- Department of Ultrasound, The Second People's Hospital of Shenzhen, The First Affiliated Hospital of Shenzhen University, Shenzhen 518061, China
| | - Min Pan
- Shenzhen Hospital of Guangzhou University of Chinese Medicine, Shenzhen 518034, China
| | - Muhammad Fiaz
- Department of Radiology, Azra Naheed Medical College, Lahore, Pakistan
| | - Yongsheng Hao
- Center for Cell and Gene Circuit Design, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yiran Yan
- Department of Orthopedics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Litao Sun
- Cancer Center, Department of Ultrasound Medicine, Zhejiang Provincial People's Hospital (Affiliated People's Hospital, Hangzhou Medical College), Hangzhou, Zhejiang 310014, China.
| | - Fei Yan
- Center for Cell and Gene Circuit Design, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
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14
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Davis L, Back SJ. Microbubbles in the belly: optimizing the protocol for contrast-enhanced ultrasound of the pediatric abdomen. Pediatr Radiol 2022:10.1007/s00247-022-05464-x. [PMID: 36006474 DOI: 10.1007/s00247-022-05464-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/20/2022] [Accepted: 07/19/2022] [Indexed: 11/30/2022]
Abstract
Intravenous contrast-enhanced ultrasound (CEUS) can serve as a diagnostic or problem-solving tool in pediatric imaging. CEUS of abdominal solid organs has been reported for a number of indications. The approach to the examination broadly falls into two categories: evaluation of a focal lesion or surveillance of an organ or organs for lesions or perfusion abnormalities. A consistent, technical imaging protocol for both of these clinical scenarios facilitates integration of routine use of CEUS in an imaging department. Here we review the CEUS imaging protocols for abdominal organs in children, including technical and solid-organ-specific considerations.
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Affiliation(s)
- Lauramay Davis
- Institute of Nuclear Medicine, University College Hospital, London, UK
| | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA. .,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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15
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Bruce M, DeWees D, Harmon JN, Cates L, Khaing ZZ, Hofstetter CP. Blood Flow Changes Associated with Spinal Cord Injury Assessed by Non-linear Doppler Contrast-Enhanced Ultrasound. Ultrasound Med Biol 2022; 48:1410-1419. [PMID: 35523621 PMCID: PMC9704544 DOI: 10.1016/j.ultrasmedbio.2022.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 05/23/2023]
Abstract
Contrast-enhanced ultrasound (CEUS) is clinically used to image the microcirculation at lower imaging frequencies (<2 MHz). Recently, plane-wave acquisitions and Doppler processing have revealed improved microbubble sensitivity, enabling CEUS use at higher frequencies (15 MHz) and the ability to image simultaneously blood flow in the micro- and macrocirculations. We used this approach to assess acute and chronic blood flow changes within contused spinal cord in a rodent spinal cord injury model. Immediately after spinal cord injury, we found significant differences in perfusion deficit between moderate and severe injuries (1.73 ± 0.1 mm2 vs. 3.2 ± 0.3 mm2, respectively), as well as a delay in microbubble arrival time in tissue adjacent to the injury site (0.97 ± 0.1 s vs. 1.54 ± 0.1 s, respectively). Acutely, morphological changes to central sulcal arteries were observed where vessels rostral to the contusion were displaced 4.8 ± 2.2° and 8.2 ± 3.1° anteriorly, and vessels caudal to the contusion 17.8 ± 3.9° and 24.2 ± 4.1° posteriorly, respectively, for moderate and severe injuries. Significant correlation of the acute perfusion deficit and arrival time were found with the chronic assessment of locomotive function and histological estimate of spared spinal cord tissue.
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Affiliation(s)
- Matthew Bruce
- Applied Physics Laboratory/Center for Industrial and Medical Ultrasound, University of Washington, Seattle, Washington, USA.
| | - Dane DeWees
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Jennifer N Harmon
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Lindsay Cates
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Zin Z Khaing
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
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16
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Vidallon MLP, Teo BM, Bishop AI, Tabor RF. Next-Generation Colloidal Materials for Ultrasound Imaging Applications. Ultrasound Med Biol 2022; 48:1373-1396. [PMID: 35641393 DOI: 10.1016/j.ultrasmedbio.2022.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/31/2022] [Accepted: 04/03/2022] [Indexed: 06/15/2023]
Abstract
Ultrasound has important applications, predominantly in the field of diagnostic imaging. Presently, colloidal systems such as microbubbles, phase-change emulsion droplets and particle systems with acoustic properties and multiresponsiveness are being developed to address typical issues faced when using commercial ultrasound contrast agents, and to extend the utility of such systems to targeted drug delivery and multimodal imaging. Current technologies and increasing research data on the chemistry, physics and materials science of new colloidal systems are also leading to the development of more complex, novel and application-specific colloidal assemblies with ultrasound contrast enhancement and other properties, which could be beneficial for multiple biomedical applications, especially imaging-guided treatments. In this article, we review recent developments in new colloids with applications that use ultrasound contrast enhancement. This work also highlights the emergence of colloidal materials fabricated from or modified with biologically derived and bio-inspired materials, particularly in the form of biopolymers and biomembranes. Challenges, limitations, potential developments and future directions of these next-generation colloidal systems are also presented and discussed.
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Affiliation(s)
| | - Boon Mian Teo
- School of Chemistry, Monash University, Clayton, Victoria, Australia
| | - Alexis I Bishop
- School of Physics and Astronomy, Monash University, Clayton, Victoria, Australia
| | - Rico F Tabor
- School of Chemistry, Monash University, Clayton, Victoria, Australia.
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17
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Didier RA, Biko DM, Hwang M, Unnikrishnan S, Woźniak MM, Yusuf GT, Sridharan A. Emerging contrast-enhanced ultrasound applications in children. Pediatr Radiol 2021; 51:2418-2424. [PMID: 33791840 DOI: 10.1007/s00247-021-05045-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/27/2021] [Accepted: 03/01/2021] [Indexed: 11/25/2022]
Abstract
Ultrasound contrast agent (UCA) use in radiology is expanding beyond traditional applications such as evaluation of liver lesions, vesicoureteral reflux and echocardiography. Among emerging techniques, 3-D and 4-D contrast-enhanced ultrasound (CEUS) imaging have demonstrated potential in enhancing the accuracy of voiding urosonography and are ready for wider clinical adoption. US contrast-based lymphatic imaging has been implemented for guiding needle placement in MR lymphangiography in children. In adults, intraoperative CEUS imaging has improved diagnosis and assisted surgical management in tumor resection, and its translation to pediatric brain tumor surgery is imminent. Because of growing interest in precision medicine, targeted US molecular imaging is a topic of active preclinical research and early stage clinical translation. Finally, an exciting new development in the application of UCA is in the field of localized drug delivery and release, with a particular emphasis on treating aggressive brain tumors. Under the appropriate acoustic settings, UCA can reversibly open the blood-brain barrier, allowing drug delivery into the brain. The aim of this article is to review the emerging CEUS applications and provide evidence regarding the feasibility of these applications for clinical implementation.
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Affiliation(s)
- Ryne A Didier
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
| | - David M Biko
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Sunil Unnikrishnan
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - Magdalena M Woźniak
- Department of Pediatric Radiology, Medical University of Lublin, Lublin, Poland
| | - Gibran T Yusuf
- Department of Radiology, King's College Hospital, Denmark Hill, London, UK
| | - Anush Sridharan
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
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18
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Back SJ, Acharya PT, Bellah RD, Cohen HL, Darge K, Deganello A, Harkanyi Z, Ključevšek D, Ntoulia A, Paltiel HJ, Piskunowicz M. Contrast-enhanced ultrasound of the kidneys and adrenals in children. Pediatr Radiol 2021; 51:2198-2213. [PMID: 33978799 DOI: 10.1007/s00247-020-04849-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/19/2020] [Accepted: 09/08/2020] [Indexed: 12/12/2022]
Abstract
Pediatric applications of contrast-enhanced ultrasound (CEUS) are growing. Evaluation of the kidneys and adrenal glands in children using intravenous administration of US contrast agents, however, is still an off-label indication. Pediatric CEUS applications for kidneys are similar to those in adults, including ischemic disorders, pseudo- versus real tumors, indeterminate lesions, complex cystic lesions, complicated pyelonephritis, and abscesses. CEUS applications for evaluation of adrenal glands in children are limited, mainly focusing on the assessment and follow-up of adrenal trauma and the differentiation between an adrenal hemorrhage and a mass. This review addresses the current experience in pediatric CEUS of the kidneys and adrenal glands. By extrapolating the established knowledge for US contrast evaluations in the adult kidney to the pediatric context we can note opportunities for CEUS clinical use in children.
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Affiliation(s)
- Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Patricia T Acharya
- Department of Radiology, Children's Hospital of Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Richard D Bellah
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Harris L Cohen
- Department of Radiology, Le Bonheur Children's Hospital, Memphis, TN, USA
| | - Kassa Darge
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Annamaria Deganello
- Department of Radiology, King's College Hospital, King's College London, London, UK
| | - Zoltan Harkanyi
- Department of Radiology, Heim Pal National Pediatric Institute, Budapest, Hungary
| | - Damjana Ključevšek
- Department of Radiology, University Children's Hospital Ljubljana, Ljubljana, Slovenia
| | - Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - Harriet J Paltiel
- Department of Radiology, Boston Children's Hospital, Harvard University, Boston, MA, USA
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19
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Song R, Zhang C, Teng F, Tu J, Guo X, Fan Z, Zheng Y, Zhang D. Cavitation-facilitated transmembrane permeability enhancement induced by acoustically vaporized nanodroplets. Ultrason Sonochem 2021; 79:105790. [PMID: 34662804 PMCID: PMC8526759 DOI: 10.1016/j.ultsonch.2021.105790] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 05/05/2023]
Abstract
Ultrasound-facilitated transmembrane permeability enhancement has attracted broad attention in the treatment of central nervous system (CNS) diseases, by delivering gene/drugs into the deep site of brain tissues with a safer and more effective way. Although the feasibility of using acoustically vaporized nanodroplets to open the blood-brain-barrier (BBB) has previously been reported, the relevant physical mechanisms and impact factors are not well known. In the current study, a nitrocellulose (NC) membrane was used to mimic the multi-layered pore structure of BBB. The cavitation activity and the penetration ability of phase-changed nanodroplets were systemically evaluated at different concentration levels, and compared with the results obtained for SonoVue microbubbles. Passive cavitation detection showed that less intensified but more sustained inertial cavitation (IC) activity would be generated by vaporized nanodroplets than microbubbles. As the results, with a sufficiently high concentration (∼5 × 108/mL), phase-changed nanodroplets were more effective than microbubbles in enabling a fluorescent tracer agent (FITC, 150 kDa) to penetrate deeper and more homogeneously through the NC membrane, and a positive correlation was observed between accumulated IC dose and the amount of penetrated FITC. In vivo studies further confirmed acoustically vaporized nanodroplets performed better than microbubbles by opening the BBB in rats' brains. These results indicated that phase-changed nanodroplets can be used as a safe, efficient and durable agent to achieve satisfactory cavitation-mediated permeability enhancement effect in biomedical applications.
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Affiliation(s)
- Renjie Song
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China
| | - Chunbing Zhang
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Fengmeng Teng
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Juan Tu
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China; The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080, China.
| | - Xiasheng Guo
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China
| | - Zheng Fan
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Yinfei Zheng
- Research Center for Intelligent Sensing, Zhejiang Lab, Hangzhou 311100, China.
| | - Dong Zhang
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China; The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080, China.
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20
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Sridharan A, Eisenbrey JR, Forsberg F, Lorenz N, Steffgen L, Ntoulia A. Ultrasound contrast agents: microbubbles made simple for the pediatric radiologist. Pediatr Radiol 2021; 51:2117-27. [PMID: 34117892 DOI: 10.1007/s00247-021-05080-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 02/25/2021] [Accepted: 04/12/2021] [Indexed: 02/07/2023]
Abstract
The ability to provide prompt, real-time, easily accessible and radiation-free diagnostic assessments makes ultrasound (US) one of the most versatile imaging modalities. The introduction and development of stable microbubble-based ultrasound contrast agents (UCAs) in the early 1990s improved visualization of complex vascular structures, overcoming some of the limitations of B-mode and Doppler imaging. UCAs have been used extensively in the adult population to visualize vasculature and to evaluate perfusion and blood flow dynamics in organs and lesions. Since the first observations that air bubbles within a liquid can generate a strong echogenic effect, to the early makeshift approaches with agitated saline, and later to the development of industrially produced and federally approved UCAs, these agents have evolved to become both clinically and commercially viable. Perhaps the most exciting potential of UCAs is being uncovered by current research that explores the use of these agents for molecular imaging and therapeutic applications. As contrast-enhanced ultrasound (CEUS) becomes more widely available, it is important for pediatric radiologists to understand the physics of the interaction between the US signal and the microbubbles in order to properly utilize them for the highest level of diagnostic imaging and interventions. In this article we introduce the composition of UCAs and the physics of their behavior in US, and we offer a brief history of their development over the last decades.
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21
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Sridharan A, Hwang M, Kutty S, McCarville MB, Paltiel HJ, Piskunowicz M, Shellikeri S, Silvestro E, Taylor GA, Didier RA. Translational research in pediatric contrast-enhanced ultrasound. Pediatr Radiol 2021; 51:2425-2436. [PMID: 33991196 DOI: 10.1007/s00247-021-05095-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/21/2021] [Accepted: 04/28/2021] [Indexed: 10/21/2022]
Abstract
The role of contrast-enhanced ultrasound (CEUS) imaging is being widely explored by various groups for its use in the pediatric population. Clinical implementation of new diagnostic or therapeutic techniques requires extensive and meticulous preclinical testing and evaluation. The impact of CEUS will be determined in part by the extent to which studies are oriented specifically toward a pediatric population. Rather than simply applying principles and techniques used in the adult population, these studies are expected to advance and augment preexisting knowledge with pediatric-specific information. To further develop this imaging modality for use in children, pediatric-focused preclinical research is essential. In this paper we describe the development and implementation of the pediatric-specific preclinical animal and phantom models that are being used to evaluate CEUS with the goal of clinical translation to children.
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Affiliation(s)
- Anush Sridharan
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Shelby Kutty
- Taussig Heart Center, Johns Hopkins University, Baltimore, MD, USA
| | - M Beth McCarville
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Harriet J Paltiel
- Department of Radiology, Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | | | - Sphoorti Shellikeri
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - Elizabeth Silvestro
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - George A Taylor
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Harvard Medical School, Boston, MA, USA
| | - Ryne A Didier
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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22
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Ntoulia A, Aguirre Pascual E, Back SJ, Bellah RD, Beltrán Salazar VP, Chan PKJ, Chow JS, Coca Robinot D, Darge K, Duran C, Epelman M, Ključevšek D, Kwon JK, Sandhu PK, Woźniak MM, Papadopoulou F. Contrast-enhanced voiding urosonography, part 1: vesicoureteral reflux evaluation. Pediatr Radiol 2021; 51:2351-2367. [PMID: 33787945 DOI: 10.1007/s00247-020-04906-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/11/2020] [Accepted: 11/09/2020] [Indexed: 12/17/2022]
Abstract
Contrast-enhanced voiding urosonography (ceVUS) is a well-established, sensitive and safe ultrasound (US) modality for detecting and grading vesicoureteral reflux (VUR) and urethral imaging in children. Nearly three decades of remarkable advances in US technology and US contrast agents have refined ceVUS's diagnostic potential. The recent approval of Lumason/SonoVue in the United States, Europe and China for pediatric intravesical applications marked the beginning of a new era for this type of contrast US imaging. Consequently, the use of ceVUS in children has expanded to multiple places around the globe. In the first part of this review article, we describe the current experience in the use of ceVUS for VUR evaluation, with an emphasis on historical background, examination technique, image interpretation and diagnostic accuracy. In the second part, we will present the role of ceVUS for urethral imaging in children.
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Affiliation(s)
- Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | | | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Richard D Bellah
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Viviana P Beltrán Salazar
- Department of Radiology, Hospital Universitari Parc Tauli - Universitat Autónoma de Barcelona, Sabadell, Barcelona, Spain
| | - Pui Kwan Joyce Chan
- Department of Radiology, Hong Kong Children's Hospital, Hong Kong (SAR), People's Republic of China
| | - Jeanne S Chow
- Department of Radiology, Boston Children's Hospital, Harvard University, Boston, MA, USA
| | - David Coca Robinot
- Department of Radiology, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Kassa Darge
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Carmina Duran
- Department of Radiology, Hospital Universitari Parc Tauli - Universitat Autónoma de Barcelona, Sabadell, Barcelona, Spain
| | - Monica Epelman
- Department of Radiology, Nemours Children's Health System/Nemours Children's Hospital, Orlando, FL, USA
| | - Damjana Ključevšek
- Department of Radiology, University Children's Hospital Ljubljana, Ljubljana, Slovenia
| | - Jeannie K Kwon
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Preet Kiran Sandhu
- Department of Radiology, Le Bonheur Children's Hospital, Memphis, TN, USA
| | - Magdalena M Woźniak
- Department of Pediatric Radiology, Medical University of Lublin, Lublin, Poland
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23
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Ntoulia A, Barnewolt CE, Doria AS, Ho-Fung VM, Lorenz N, Mentzel HJ, Back SJ. Contrast-enhanced ultrasound for musculoskeletal indications in children. Pediatr Radiol 2021; 51:2303-2323. [PMID: 33783575 DOI: 10.1007/s00247-021-04964-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 09/02/2020] [Accepted: 01/07/2021] [Indexed: 12/14/2022]
Abstract
The increasing use of contrast-enhanced ultrasound (CEUS) has opened exciting new frontiers for musculoskeletal applications in adults and children. The most common musculoskeletal-related CEUS applications in adults are for detecting inflammatory joint diseases, imaging skeletal muscles and tendon perfusion, imaging postoperative viability of osseous and osseocutaneous tissue flaps, and evaluating the malignant potential of soft-tissue masses. Pediatric musculoskeletal-related CEUS has been applied for imaging juvenile idiopathic arthritis and Legg-Calvé-Perthes disease and for evaluating femoral head perfusion following surgical hip reduction in children with developmental hip dysplasia. CEUS can improve visualization of the capillary network in superficial and deep tissues and also in states of slow- or low-volume blood flow. In addition, measurements of blood flow imaging parameters performed by quantitative CEUS are valuable when monitoring the outcome of treatment interventions. In this review article we present current experience regarding a wide range of CEUS applications in musculoskeletal conditions in adults and children, with emphasis on the latter, and discuss imaging techniques and CEUS findings in musculoskeletal applications.
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Affiliation(s)
- Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Carol E Barnewolt
- Department of Radiology, Boston Children's Hospital, Harvard University, Boston, MA, USA
| | - Andrea S Doria
- Department of Medical Imaging, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Victor M Ho-Fung
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Norbert Lorenz
- Children's Hospital, Dresden Municipal Hospital, Teaching-Hospital of Technical University, Dresden, Germany
| | - Hans-Joachim Mentzel
- Section of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, University Hospital of Jena, Jena, Germany
| | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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24
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Kutty S, Biko DM, Goldberg AB, Quartermain MD, Feinstein SB. Contrast-enhanced ultrasound in pediatric echocardiography. Pediatr Radiol 2021; 51:2408-2417. [PMID: 34244848 DOI: 10.1007/s00247-021-05119-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/29/2021] [Accepted: 06/01/2021] [Indexed: 11/25/2022]
Abstract
The safety and benefits of cardiac contrast-enhanced ultrasound (CEUS) have been demonstrated in children and adolescents for a variety of clinical indications, including congenital heart disease. Cardiac CEUS is performed with US and the intravenous administration of ultrasound contrast agents (UCAs). It improves transthoracic echocardiography, which can be challenging in children and adults with acoustic window limitations (e.g., from obesity) and alterations in chest wall and cardiac geometry (e.g., from prior surgical procedures). Cardiac CEUS is also used to evaluate ischemia in the follow-up of congenital and acquired heart disease. In 2019, the United States Food and Drug Administration (FDA) approved a UCA for pediatric echocardiography. This article focuses on the clinical applications of UCAs in pediatric and adult echocardiography, outlining its diagnostic value, safety and potential for future applications.
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Affiliation(s)
- Shelby Kutty
- Helen B. Taussig Heart Center, The Johns Hopkins University School of Medicine, 1800 Orleans St., Baltimore, MD, 21287, USA.
| | - David M Biko
- Department of Radiology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alan B Goldberg
- Division of Cardiology, Rush University Medical Center, Chicago, IL, USA
| | - Michael D Quartermain
- Division of Cardiology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Steven B Feinstein
- Division of Cardiology, Rush University Medical Center, Chicago, IL, USA
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25
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Acord MR, Cahill AM, Durand R, Huang DY, Shellikeri S, Vatsky S, Srinivasan A. Contrast-enhanced ultrasound in pediatric interventional radiology. Pediatr Radiol 2021; 51:2396-407. [PMID: 33978796 DOI: 10.1007/s00247-020-04853-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/14/2020] [Accepted: 09/10/2020] [Indexed: 01/14/2023]
Abstract
There is growing interest in the use of contrast-enhanced ultrasound (CEUS) in diagnostic and interventional radiology. CEUS applications in interventional radiology are performed with intravascular or intracavitary administration of microbubble-based US contrast agents to allow for real-time evaluation of their distribution within the vascular bed or in body cavities, respectively, providing additional information beyond gray-scale US alone. The most common interventional-radiology-related CEUS applications in children have been extrapolated from those in adults, and they include the use of CEUS to guide lesion biopsy and to confirm drain placement in pleural effusions and intra-abdominal fluid collections. Other applications are emerging in interventional radiology for use in adults and children, including CEUS to optimize sclerotherapy of vascular malformations, to guide arthrography, and for lymphatic interventions. In this review article we present a wide range of interventional-radiology-related CEUS applications, emphasizing the current and potential uses in children. We highlight the technical parameters of the CEUS examination and discuss the main imaging findings.
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26
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Barnewolt CE, Acharya PT, Aguirre Pascual E, Back SJ, Beltrán Salazar VP, Chan PKJ, Chow JS, Coca Robinot D, Darge K, Duran C, Ključevšek D, Kwon JK, Ntoulia A, Papadopoulou F, Woźniak MM, Piskunowicz M. Contrast-enhanced voiding urosonography part 2: urethral imaging. Pediatr Radiol 2021; 51:2368-2386. [PMID: 34386854 DOI: 10.1007/s00247-021-05116-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/17/2021] [Accepted: 05/26/2021] [Indexed: 11/30/2022]
Abstract
Ultrasound (US) has been increasingly used as an important imaging tool to assess the urethra in children. The earliest reports of pediatric urethral sonography involved imaging the urethra in a non-voiding state, during physiological voiding of urine, and after instillation of saline. The introduction of US contrast agents has continued to improve visualization of urethral anatomy. Contrast-enhanced US of the urethra can be performed during the voiding phase of a standard contrast-enhanced voiding urosonography (ceVUS) exam or with retrograde instillation of a contrast agent, depending on the exam indication. Both techniques are well tolerated by children and provide accurate information about urethral pathology and periurethral soft tissues. This article reviews the technical aspects and imaging findings of urethral pathologies in children using contrast-enhanced US, both by the voiding and retrograde instillation techniques.
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Affiliation(s)
- Carol E Barnewolt
- Department of Radiology, Boston Children's Hospital, Harvard University, 300 Longwood Ave., Boston, MA, 02115, USA.
| | - Patricia T Acharya
- Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | | | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Vivian P Beltrán Salazar
- Department of Radiology, Hospital Universitari Parc Taulí - Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Pui Kwan Joyce Chan
- Department of Radiology, Hong Kong Children's Hospital, Hong Kong (SAR), People's Republic of China
| | - Jeanne S Chow
- Department of Radiology, Boston Children's Hospital, Harvard University, 300 Longwood Ave., Boston, MA, 02115, USA
| | - David Coca Robinot
- Department of Radiology, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Kassa Darge
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Carmina Duran
- Department of Radiology, Hospital Universitari Parc Taulí - Universitat Autònoma de Barcelona, Sabadell, Barcelona, Spain
| | - Damjana Ključevšek
- Department of Radiology, University Children's Hospital Ljubljana, Ljubljana, Slovenia
| | - Jeannie K Kwon
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Magdalena M Woźniak
- Department of Pediatric Radiology, Medical University of Lublin, Lublin, Poland
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27
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Ntoulia A, Anupindi SA, Back SJ, Didier RA, Hwang M, Johnson AM, McCarville MB, Papadopoulou F, Piskunowicz M, Sellars ME, Darge K. Contrast-enhanced ultrasound: a comprehensive review of safety in children. Pediatr Radiol 2021; 51:2161-2180. [PMID: 34716453 DOI: 10.1007/s00247-021-05223-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/10/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022]
Abstract
Contrast-enhanced ultrasound (CEUS) has been increasingly used in pediatric radiology practice worldwide. For nearly two decades, CEUS applications have been performed with the off-label use of gas-containing second-generation ultrasound contrast agents (UCAs). Since 2016, the United States Food and Drug Administration (FDA) has approved the UCA Lumason for three pediatric indications: the evaluation of focal liver lesions and echocardiography via intravenous administration and the assessment of vesicoureteral reflux via intravesical application (contrast-enhanced voiding urosonography, ceVUS). Prior to the FDA approval of Lumason, numerous studies with the use of second-generation UCAs had been conducted in adults and children. Comprehensive protocols for clinical safety evaluations have demonstrated the highly favorable safety profile of UCA for intravenous, intravesical and other intracavitary uses. The safety data on CEUS continue to accumulate as this imaging modality is increasingly utilized in clinical settings worldwide. As of August 2021, 57 pediatric-only original research studies encompassing a total of 4,518 children with 4,906 intravenous CEUS examinations had been published. As in adults, there were a few adverse events; the majority of these were non-serious, although very rarely serious anaphylactic reactions were reported. In the published pediatric-only intravenous CEUS studies included in our analysis, the overall incidence rate of serious adverse events was 0.22% (10/4,518) of children and 0.20% (10/4,906) of all CEUS examinations. Non-serious adverse events from the intravenous CEUS were observed in 1.20% (54/4,518) of children and 1.10% (54/4,906) of CEUS examinations. During the same time period, 31 studies with the intravesical use of UCA were conducted in 12,362 children. A few non-serious adverse events were encountered (0.31%; 38/12,362), but these were most likely attributable to the bladder catheterization rather than the UCA. Other developing clinical applications of UCA in children, including intracavitary and intralymphatic, are ongoing. To date, no serious adverse events have been reported with these applications. This article reviews the existing pediatric CEUS literature and provides an overview of safety-related information reported from UCA uses in children.
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Affiliation(s)
- Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Sudha A Anupindi
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ryne A Didier
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ann M Johnson
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - M Beth McCarville
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | | | | | - Maria E Sellars
- Department of Radiology, King's College Hospital, London, UK
| | - Kassa Darge
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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28
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Paltiel HJ, Barth RA, Bruno C, Chen AE, Deganello A, Harkanyi Z, Henry MK, Ključevšek D, Back SJ. Contrast-enhanced ultrasound of blunt abdominal trauma in children. Pediatr Radiol 2021; 51:2253-2269. [PMID: 33978795 DOI: 10.1007/s00247-020-04869-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 08/26/2020] [Accepted: 09/30/2020] [Indexed: 12/13/2022]
Abstract
Trauma is the leading cause of morbidity and mortality in children, and rapid identification of organ injury is essential for successful treatment. Contrast-enhanced ultrasound (CEUS) is an appealing alternative to contrast-enhanced CT in the evaluation of children with blunt abdominal trauma, mainly with respect to the potential reduction of population-level exposure to ionizing radiation. This is particularly important in children, who are more vulnerable to the hazards of ionizing radiation than adults. CEUS is useful in hemodynamically stable children with isolated blunt low- to moderate-energy abdominal trauma to rule out solid organ injuries. It can also be used to further evaluate uncertain contrast-enhanced CT findings, as well as in the follow-up of conservatively managed traumatic injuries. CEUS can be used to detect abnormalities that are not apparent by conventional US, including infarcts, pseudoaneurysms and active bleeding. In this article we present the current experience from the use of CEUS for the evaluation of pediatric blunt abdominal trauma, emphasizing the examination technique and interpretation of major abnormalities associated with injuries in the liver, spleen, kidneys, adrenal glands, pancreas and testes. We also discuss the limitations of the technique and offer a review of the major literature on this topic in children, including an extrapolation of experience from adults.
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Affiliation(s)
- Harriet J Paltiel
- Department of Radiology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA, 02115, USA.
| | - Richard A Barth
- Department of Radiology, Lucile Packard Children's Hospital at Stanford, Stanford University School of Medicine, Stanford, CA, USA
| | - Costanza Bruno
- Department of Radiology, Azienda Ospedaliera Universitaria Integrata, University of Verona, Verona, Italy
| | - Aaron E Chen
- Department of Pediatrics, Division of Emergency Medicine, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Zoltan Harkanyi
- Department of Radiology, Heim Pal National Pediatric Institute, Budapest, Hungary
| | - M Katherine Henry
- Safe Place: The Center for Child Protection and Health, Division of General Pediatrics, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Radiology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Damjana Ključevšek
- Department of Radiology, University Children's Hospital Ljubljana, Ljubljana, Slovenia
| | - Susan J Back
- Department of Radiology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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29
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Franke D, Daugherty RJ, Ključevšek D, Ntoulia A, Rafailidis V, Takahashi MS, Torres A, Viteri B, Volberg FM. Contrast-enhanced ultrasound of transplant organs - liver and kidney - in children. Pediatr Radiol 2021; 51:2284-302. [PMID: 33978794 DOI: 10.1007/s00247-020-04867-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/13/2020] [Accepted: 09/30/2020] [Indexed: 10/21/2022]
Abstract
Ultrasound (US) is the first-line imaging tool for evaluating liver and kidney transplants during and after the surgical procedures. In most patients after organ transplantation, gray-scale US coupled with color/power and spectral Doppler techniques is used to evaluate the transplant organs, assess the patency of vascular structures, and identify potential complications. In technically difficult or inconclusive cases, however, contrast-enhanced ultrasound (CEUS) can provide prompt and accurate diagnostic information that is essential for management decisions. CEUS is indicated to evaluate for vascular complications including vascular stenosis or thrombosis, active bleeding, pseudoaneurysms and arteriovenous fistulas. Parenchymal indications for CEUS include evaluation for perfusion defects and focal inflammatory and non-inflammatory lesions. When transplant rejection is suspected, CEUS can assist with prompt intervention by excluding potential underlying causes for organ dysfunction. Intracavitary CEUS applications can evaluate the biliary tract of a liver transplant (e.g., for biliary strictures, bile leak or intraductal stones) or the urinary tract of a renal transplant (e.g., for urinary obstruction, urine leak or vesicoureteral reflux) as well as the position and patency of hepatic, biliary and renal drains and catheters. The aim of this review is to present current experience regarding the use of CEUS to evaluate liver and renal transplants, focusing on the examination technique and interpretation of the main imaging findings, predominantly those related to vascular complications.
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30
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Hwang M, Barnewolt CE, Jüngert J, Prada F, Sridharan A, Didier RA. Contrast-enhanced ultrasound of the pediatric brain. Pediatr Radiol 2021; 51:2270-2283. [PMID: 33599780 DOI: 10.1007/s00247-021-04974-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/10/2020] [Accepted: 01/14/2021] [Indexed: 12/16/2022]
Abstract
Brain contrast-enhanced ultrasound (CEUS) is an emerging application that can complement gray-scale US and yield additional insights into cerebral flow dynamics. CEUS uses intravenous injection of ultrasound contrast agents (UCAs) to highlight tissue perfusion and thus more clearly delineate cerebral pathologies including stroke, hypoxic-ischemic injury and focal lesions such as tumors and vascular malformations. It can be applied not only in infants with open fontanelles but also in older children and adults via a transtemporal window or surgically created acoustic window. Advancements in CEUS technology and post-processing methods for quantitative analysis of UCA kinetics further elucidate cerebral microcirculation. In this review article we discuss the CEUS examination protocol for brain imaging in children, current clinical applications and future directions for research and clinical uses of brain CEUS.
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Affiliation(s)
- Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA. .,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Carol E Barnewolt
- Department of Radiology, Boston Children's Hospital, Harvard University, Boston, MA, USA
| | - Jörg Jüngert
- Department of Pediatrics, Friedrich-Alexander University Erlangen - Nürnberg, Erlangen, Germany
| | - Francesco Prada
- Acoustic Neuroimaging and Therapy Laboratory, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.,Department of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA.,Focused Ultrasound Foundation, Charlottesville, VA, USA
| | - Anush Sridharan
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - Ryne A Didier
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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31
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Franke D, Anupindi SA, Barnewolt CE, Green TG, Greer MLC, Harkanyi Z, Lorenz N, McCarville MB, Mentzel HJ, Ntoulia A, Squires JH. Contrast-enhanced ultrasound of the spleen, pancreas and gallbladder in children. Pediatr Radiol 2021; 51:2229-2252. [PMID: 34431006 DOI: 10.1007/s00247-021-05131-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 04/30/2021] [Accepted: 06/10/2021] [Indexed: 12/14/2022]
Abstract
Gray-scale and color/power Doppler ultrasound (US) are the first-line imaging modalities to evaluate the spleen, gallbladder and pancreas in children. The increasing use of contrast-enhanced ultrasound (CEUS) as a reliable and safe method to evaluate liver lesions in the pediatric population promises potential for imaging other internal organs. Although CEUS applications of the spleen, gallbladder and pancreas have been well described in adults, they have not been fully explored in children. In this manuscript, we present an overview of the applications of CEUS for normal variants and diseases affecting the spleen, gallbladder and pancreas. We highlight a variety of cases as examples of how CEUS can serve in the diagnosis and follow-up for such diseases in children. Our discussion includes specific examination techniques; presentation of the main imaging findings in various benign and malignant lesions of the spleen, gallbladder and pancreas in children; and acknowledgment of the limitations of CEUS for these organs.
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Affiliation(s)
- Doris Franke
- Department of Pediatric Kidney, Liver and Metabolic Diseases, MHH, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
| | - Sudha A Anupindi
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Carol E Barnewolt
- Department of Radiology, Boston Children's Hospital, Harvard University, Boston, MA, USA
| | - Thomas G Green
- Department of Radiology, Crouse Hospital, Syracuse, NY, USA
| | - Mary-Louise C Greer
- Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, Toronto, ON, Canada
| | - Zoltan Harkanyi
- Department of Radiology, Heim Pal National Pediatric Institute, Budapest, Hungary
| | - Norbert Lorenz
- Children's Hospital, Dresden Municipal Hospital, Teaching-Hospital of Technical University Dresden, Dresden, Germany
| | - M Beth McCarville
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Hans-Joachim Mentzel
- Section of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, University Hospital, Jena, Germany
| | - Aikaterini Ntoulia
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Judy H Squires
- Department of Radiology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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32
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Darge K, Back SJ, Barth RA, Johnson AM, Kwon JK, McCarville MB, Morgan TA, Ntoulia A, Poznick L, Shellikeri S, Srinivasan AS, Cahill AM. Starting a pediatric contrast ultrasound service: made simple! Pediatr Radiol 2021; 51:2139-46. [PMID: 33978800 DOI: 10.1007/s00247-021-04998-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/17/2020] [Accepted: 02/03/2021] [Indexed: 10/21/2022]
Abstract
The addition of contrast US to an existing pediatric US service requires several preparatory steps. This overview provides a guide to simplify the process. Initially, it is important to communicate to all stakeholders the justifications for pediatric contrast US, including (1) its comparable or better diagnostic results relative to other modalities; (2) its reduction in procedural sedation or anesthesia by avoiding MRI or CT; (3) its reduction or elimination of radiation exposure by not having to perform fluoroscopy or CT; (4) the higher safety profile of US contrast agents (UCA) compared to other contrast agents; (5) the improved exam comfort and ease inherent to US, leading to better patient and family experience, including bedside US exams for children who cannot be transported; (6) the need for another diagnostic option in light of increasing demand by parents and providers; and (7) its status as an approved and reimbursable exam. It is necessary to have an UCA incorporated into the pharmacy formulary noting that only SonoVue/Lumason is currently approved for pediatric use. In the United States this UCA is approved for intravenous administration for cardiac and liver imaging and for vesicoureteric reflux detection with intravesical application. In Europe and China it is only approved for the intravesical use in children. All other applications are off-label. The US scanner needs to be equipped with contrast-specific software. The UCA has to be prepared just before the exam and it is important to strictly follow the steps as outlined in the packaging inserts in order to prevent premature destruction of the microbubbles. The initial training in contrast US is best focused on the frontline staff actually performing the US studies; these might be sonographers, pediatric or interventional radiologists, or trainees. It is important from the outset to educate the referring physicians about contrast US. It is helpful to participate in existing contrast US courses, particularly those with hands-on components.
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33
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Gümmer J, Schenke S, Denner F. Modelling Lipid-Coated Microbubbles in Focused Ultrasound Applications at Subresonance Frequencies. Ultrasound Med Biol 2021; 47:2958-2979. [PMID: 34344560 DOI: 10.1016/j.ultrasmedbio.2021.06.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 06/15/2021] [Accepted: 06/20/2021] [Indexed: 06/13/2023]
Abstract
We present a computational study of the behaviour of a lipid-coated SonoVue microbubble with initial radius 1 µm ≤ R0 ≤ 2 µm, excited at frequencies (200-1500 kHz) significantly below the linear resonance frequency and pressure amplitudes of up to 1500 kPa-an excitation regime used in many applications of focused ultrasound. The bubble dynamics are simulated using the Rayleigh-Plesset equation and the Gilmore equation, in conjunction with the Marmottant model for the lipid monolayer coating. Also, a new continuously differentiable variant of the Marmottant model is introduced. Below the onset of inertial cavitation, a linear regime is identified in which the maximum pressure at the bubble wall is linearly proportional to the excitation pressure amplitude and the mechanical index. This linear regime is bounded by the Blake pressure, and, in line with recent in vitro experiments, the onset of inertial cavitation is found to occur at an excitation pressure amplitude of approximately 130-190 kPa, depending on the initial bubble size. In the nonlinear regime the maximum pressure at the bubble wall is found to be readily predicted by the maximum bubble radius, and both the Rayleigh-Plesset and Gilmore equations are shown to predict the onset of sub- and ultraharmonic frequencies of the acoustic emissions compared with in vitro experiments. Neither the surface dilational viscosity of the lipid monolayer nor the compressibility of the liquid has a discernible influence on the quantities studied, but accounting for the lipid coating is critical for accurate prediction of the bubble behaviour. The Gilmore equation is shown to be valid for the bubbles and excitation regime considered, and the Rayleigh-Plesset equation also provides accurate qualitative predictions, even though it is outside its range of validity for many of the cases considered.
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Affiliation(s)
- Jonas Gümmer
- Chair of Mechanical Process Engineering, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
| | - Sören Schenke
- Chair of Mechanical Process Engineering, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
| | - Fabian Denner
- Chair of Mechanical Process Engineering, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany.
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34
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Clark A, Bonilla S, Suo D, Shapira Y, Averkiou M. Microbubble-Enhanced Heating: Exploring the Effect of Microbubble Concentration and Pressure Amplitude on High-Intensity Focused Ultrasound Treatments. Ultrasound Med Biol 2021; 47:2296-2309. [PMID: 33985825 PMCID: PMC8243806 DOI: 10.1016/j.ultrasmedbio.2021.03.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 03/25/2021] [Accepted: 03/29/2021] [Indexed: 05/11/2023]
Abstract
High-intensity focused ultrasound (HIFU) is a non-invasive tool that can be used for targeted thermal ablation treatments. Currently, HIFU is clinically approved for treatment of uterine fibroids, various cancers, and certain brain applications. However, for brain applications such as essential tremors, HIFU can only be used to treat limited areas confined to the center of the brain because of geometrical limitations (shape of the transducer and skull). A major obstacle to advancing this technology is the inability to treat non-central brain locations without causing damage to the skin and/or skull. Previous research has indicated that cavitation-induced bubbles or microbubble contrast agents can be used to enhance HIFU treatments by increasing ablation regions and shortening acoustic exposures at lower acoustic pressures. However, little research has been done to explore the interplay between microbubble concentration and pressure amplitude on HIFU treatments. We developed an in vitro experimental setup to study lesion formation at three different acoustic pressures and three microbubble concentrations. Real-time ultrasound imaging was integrated to monitor initial microbubble concentration and subsequent behavior during the HIFU treatments. Depending on the pressure used for the HIFU treatment, there was an optimal concentration of microbubbles that led to enhanced heating in the focal area. If the concentration of microbubbles was too high, the treatment was detrimentally affected because of non-linear attenuation by the pre-focal microbubbles. Additionally, the real-time ultrasound imaging provided a reliable method to monitor microbubble activity during the HIFU treatments, which is important for translation to in vivo HIFU applications with microbubbles.
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Affiliation(s)
- Alicia Clark
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Sierra Bonilla
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Dingjie Suo
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | | | - Michalakis Averkiou
- Department of Bioengineering, University of Washington, Seattle, Washington, USA.
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35
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Vetrano IG, Gennari AG, Erbetta A, Acerbi F, Nazzi V, DiMeco F, Prada F. Contrast-Enhanced Ultrasound Assisted Surgery of Intramedullary Spinal Cord Tumors: Analysis of Technical Benefits and Intra-operative Microbubble Distribution Characteristics. Ultrasound Med Biol 2021; 47:398-407. [PMID: 33349517 DOI: 10.1016/j.ultrasmedbio.2020.10.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 10/22/2020] [Accepted: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Intra-operative contrast-enhanced ultrasound (CEUS) is a relatively standardized procedure in brain neurosurgery, but it is still underused in spinal cord and intramedullary tumor evaluation. We reviewed and analyzed the intra-operative data from a surgical series of patients harboring intramedullary spinal cord tumors who underwent surgery under CEUS guidance. CEUS was performed in 12 patients (age range: 13-55 y); all lesions had ill-defined boundaries or peritumoral cysts at preliminary intra-operative B-mode ultrasound. CEUS highlighted the tumors in all cases. The contrast agent's spinal distribution revealed different phases (arterial, peak, washout), as observed in the brain, but these appeared to be slower and less intense. In our experience, intra-operative CEUS allows surgeons to assess spinal cord perfusion and highlight intramedullary tumors in real time. As for other imaging modalities, ultrasound contrast agents add valuable information over baseline imaging, and their use should be fostered to better understand microbubble distribution dynamics.
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Affiliation(s)
- Ignazio G Vetrano
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Antonio G Gennari
- Department of Radiology, Cattinara Hospital, University of Trieste, Trieste, Italy; Department of Neuroradiology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Alessandra Erbetta
- Department of Neuroradiology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Francesco Acerbi
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Vittoria Nazzi
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Francesco DiMeco
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy; Department of Neurological Surgery, Johns Hopkins University, Baltimore, Maryland, USA
| | - Francesco Prada
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy; Department of Neurological Surgery, University of Virginia Health Science Center, Charlottesville, Virginia, USA; Focused Ultrasound Foundation, Charlottesville, Virginia, USA.
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36
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Piskunowicz M, Back SJ, Darge K, Humphries PD, Jüngert J, Ključevšek D, Lorenz N, Mentzel HJ, Squires JH, Huang DY. Contrast-enhanced ultrasound of the small organs in children. Pediatr Radiol 2021; 51:2324-2339. [PMID: 33830288 PMCID: PMC8566395 DOI: 10.1007/s00247-021-05006-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/17/2020] [Accepted: 02/08/2021] [Indexed: 11/28/2022]
Abstract
In pediatric and adult populations, intravenous contrast-enhanced ultrasound (CEUS) remains off-label for imaging of organs other than the liver and heart. This limited scope inhibits potential benefits of the new modality from a more widespread utilization. Yet, CEUS is potentially useful for imaging small organs such as the thyroid gland, lymph nodes, testes, ovaries and uterus, with all having locations and vasculature favorable for this type of examination. In the adult population, the utility of CEUS has been demonstrated in a growing number of studies for the evaluation of these small organs. The aim of this article is to present a review of pediatric CEUS of the thyroid gland, lymph nodes, testes, ovaries and uterus as well as to draw from the adult literature indications for possible applications in children.
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Affiliation(s)
- Maciej Piskunowicz
- Department of Radiology, Medical University of Gdansk, M. Sklodowskiej-Curie 3a Street, 80-210, Gdansk, Poland.
| | - Susan J. Back
- grid.25879.310000 0004 1936 8972Department of Radiology, Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
| | - Kassa Darge
- grid.25879.310000 0004 1936 8972Department of Radiology, Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
| | - Paul D. Humphries
- grid.424537.30000 0004 5902 9895Department of Radiology, Great Ormond Street Hospital for Children NHS Trust, London, UK
| | - Jörg Jüngert
- grid.5330.50000 0001 2107 3311Department of Pediatrics, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Damjana Ključevšek
- grid.29524.380000 0004 0571 7705Department of Radiology, University Children’s Hospital Ljubljana, Ljubljana, Slovenia
| | - Norbert Lorenz
- grid.4488.00000 0001 2111 7257Children’s Hospital, Dresden Municipal Hospital, Teaching-Hospital of Technical University Dresden, Dresden, Germany
| | - Hans-Joachim Mentzel
- grid.275559.90000 0000 8517 6224Section of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, University Hospital, Jena, Germany
| | - Judy H. Squires
- grid.239553.b0000 0000 9753 0008Department of Radiology, University of Pittsburgh Medical Center, Children’s Hospital of Pittsburgh, Pittsburgh, PA USA
| | - Dean Y. Huang
- grid.46699.340000 0004 0391 9020Department of Radiology, King’s College Hospital, Denmark Hill, London, UK
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37
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Gokli A, Dillman JR, Humphries PD, Ključevšek D, Mentzel HJ, Rubesova E, Takahashi MS, Anupindi SA. Contrast-enhanced ultrasound of the pediatric bowel. Pediatr Radiol 2021; 51:2214-2228. [PMID: 33978797 PMCID: PMC8113288 DOI: 10.1007/s00247-020-04868-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/13/2020] [Accepted: 09/30/2020] [Indexed: 01/03/2023]
Abstract
Contrast-enhanced ultrasound (CEUS) has emerged as a valuable modality for bowel imaging in adults and children. CEUS enables visualization of the perfusion of the bowel wall and of the associated mesentery in healthy and disease states. In addition, CEUS images can be used to make quantitative measurements of contrast kinetics, allowing for objective assessment of bowel wall enhancement. Bowel CEUS is commonly applied to evaluate inflammatory bowel disease and to monitor treatment response. It has also been applied to evaluate necrotizing enterocolitis, intussusception, appendicitis and epiploic appendagitis, although experience with these applications is more limited. In this review article, we present the current experience using CEUS to evaluate the pediatric bowel with emphasis on inflammatory bowel disease, extrapolating the established experience from adult studies. We also discuss emerging applications of CEUS as an adjunct or problem-solving tool for evaluating bowel perfusion.
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Affiliation(s)
- Ami Gokli
- Department of Radiology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Jonathan R. Dillman
- grid.239573.90000 0000 9025 8099Department of Radiology, Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH USA
| | - Paul D. Humphries
- grid.420468.cUniversity College London Hospital NHS Trust, Great Ormond Street Hospital for Children, London, UK
| | - Damjana Ključevšek
- grid.29524.380000 0004 0571 7705Department of Radiology, University Children’s Hospital Ljubljana, Ljubljana, Slovenia
| | - Hans-Joachim Mentzel
- grid.275559.90000 0000 8517 6224Section of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, University Hospital Jena, Jena, Germany
| | - Erika Rubesova
- grid.240952.80000000087342732Department of Radiology, Lucile Packard Children’s Hospital, Stanford University Medical Center, Stanford, CA USA
| | - Marcelo S. Takahashi
- Pediatric Radiology Department, Diagnósticos da America (DASA), São Paulo, Brazil
| | - Sudha A. Anupindi
- grid.25879.310000 0004 1936 8972Department of Radiology, Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, 3401 Civic Center Blvd., Philadelphia, PA 19104 USA
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38
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Fang C, Anupindi SA, Back SJ, Franke D, Green TG, Harkanyi Z, Jüngert J, Kwon JK, Paltiel HJ, Squires JH, Zefov VN, McCarville MB. Contrast-enhanced ultrasound of benign and malignant liver lesions in children. Pediatr Radiol 2021; 51:2181-2197. [PMID: 33978801 PMCID: PMC8566652 DOI: 10.1007/s00247-021-04976-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/17/2020] [Accepted: 01/14/2021] [Indexed: 12/14/2022]
Abstract
Contrast-enhanced ultrasound (CEUS) is increasingly being used in children. One of the most common referrals for CEUS performance is characterization of indeterminate focal liver lesions and follow-up of known liver lesions. In this setting, CEUS is performed with intravenous administration of ultrasound contrast agents (UCAs). When injected into a vein, UCA microbubbles remain confined within the vascular network until they dissipate. Therefore, visualization of UCA within the tissues and lesions corresponds to true blood flow. CEUS enables continuous, real-time observation of the enhancement pattern of a focal liver lesion, allowing in most cases for a definite diagnosis and obviating the need for further cross-sectional imaging or other interventional procedures. The recent approval of Lumason (Bracco Diagnostics, Monroe Township, NJ) for pediatric liver CEUS applications has spurred the widespread use of CEUS. In this review article we describe the role of CEUS in pediatric liver applications, focusing on the examination technique and interpretation of main imaging findings of the most commonly encountered benign and malignant focal liver lesions. We also compare the diagnostic performance of CEUS with other imaging modalities for accurate characterization of focal liver lesions.
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Affiliation(s)
- Cheng Fang
- Department of Radiology, King's College Hospital, Denmark Hill, London, SE5 9RS, UK.
| | - Sudha A. Anupindi
- Department of Radiology, Perelman School of Medicine, Children’s Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA USA
| | - Susan J. Back
- Department of Radiology, Perelman School of Medicine, Children’s Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA USA
| | - Doris Franke
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | | | - Zoltan Harkanyi
- Department of Radiology, Heim Pál National Pediatric Institute, Budapest, Hungary
| | - Jörg Jüngert
- Department of Pediatrics, Friedrich-Alexander University Erlangen–Nürnberg, Erlangen, Germany
| | - Jeannie K. Kwon
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX USA
| | - Harriet J. Paltiel
- Department of Radiology, Harvard Medical School, Boston Children’s Hospital, Boston, MA USA
| | - Judy H. Squires
- Department of Radiology, Children’s Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA USA
| | - Vassil N. Zefov
- Department of Radiology, Dubai Health Authority, Latifa Women and Children Hospital, Dubai, UAE
| | - M. Beth McCarville
- Department of Diagnostic Imaging, St. Jude Children’s Research Hospital, Memphis, TN USA
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Rafailidis V, Andronikou S, Mentzel HJ, Piskunowicz M, Squires JH, Barnewolt CE. Contrast-enhanced ultrasound of pediatric lungs. Pediatr Radiol 2021; 51:2340-2350. [PMID: 33978798 PMCID: PMC8566417 DOI: 10.1007/s00247-020-04914-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/14/2020] [Accepted: 11/09/2020] [Indexed: 12/14/2022]
Abstract
In addition to radiography, ultrasound (US) has long proved to be a valuable imaging modality to evaluate the pediatric lung and pleural cavity. Its many inherent advantages, including real-time performance, high spatial resolution, lack of ionizing radiation and lack of need for sedation make it preferable over other imaging modalities such as CT. Since the introduction of ultrasound contrast agents (UCAs), contrast-enhanced ultrasound (CEUS) has become a valuable complementary US technique, with many well-established uses in adults and evolving uses in children. Lung CEUS applications are still not licensed and are performed off-label, although the added value of CEUS in certain clinical scenarios is increasingly reported. The limited evidence of CEUS in the evaluation of pediatric lungs focuses primarily on community-acquired pneumonia and its complications. In this clinical setting, CEUS is used to confidently and accurately diagnose necrotizing pneumonia and to delineate pleural effusions and empyema. In addition to intravenous use, UCAs can be administered directly into the pleural cavity through chest catheters to improve visualization of loculations within a complex pleural effusion, which might necessitate fibrinolytic therapy. The purpose of this paper is to present the current experience on pediatric lung CEUS and to suggest potential additional uses that can be derived from adult studies.
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Affiliation(s)
- Vasileios Rafailidis
- Department of Radiology, King's College Hospital, Denmark Hill, London, SE5 9RS, UK.
| | - Savvas Andronikou
- Department of Radiology, Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
| | - Hans-Joachim Mentzel
- Section of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, University Hospital, Jena, Germany
| | | | - Judy H. Squires
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA USA
| | - Carol E. Barnewolt
- Department of Radiology, Boston Children’s Hospital, Harvard University, Boston, MA USA
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40
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Bezer JH, Koruk H, Rowlands CJ, Choi JJ. Elastic Deformation of Soft Tissue-Mimicking Materials Using a Single Microbubble and Acoustic Radiation Force. Ultrasound Med Biol 2020; 46:3327-3338. [PMID: 32919812 PMCID: PMC7605868 DOI: 10.1016/j.ultrasmedbio.2020.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 06/04/2023]
Abstract
Mechanical effects of microbubbles on tissues are central to many emerging ultrasound applications. Here, we investigated the acoustic radiation force a microbubble exerts on tissue at clinically relevant therapeutic ultrasound parameters. Individual microbubbles administered into a wall-less hydrogel channel (diameter: 25-100 µm, Young's modulus: 2-8.7 kPa) were exposed to an acoustic pulse (centre frequency: 1 MHz, pulse length: 10 ms, peak-rarefactional pressures: 0.6-1.0 MPa). Using high-speed microscopy, each microbubble was tracked as it pushed against the hydrogel wall. We found that a single microbubble can transiently deform a soft tissue-mimicking material by several micrometres, producing tissue loading-unloading curves that were similar to those produced using other indentation-based methods. Indentation depths were linked to gel stiffness. Using a mathematical model fitted to the deformation curves, we estimated the radiation force on each bubble (typically tens of nanonewtons) and the viscosity of the gels. These results provide insight into the forces exerted on tissues during ultrasound therapy and indicate a potential source of bio-effects.
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Affiliation(s)
- James H Bezer
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Hasan Koruk
- Mechanical Engineering Department, MEF University, Istanbul, Turkey
| | | | - James J Choi
- Department of Bioengineering, Imperial College London, London, United Kingdom.
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41
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Helbert A, Gaud E, Segers T, Botteron C, Frinking P, Jeannot V. Monodisperse versus Polydisperse Ultrasound Contrast Agents: In Vivo Sensitivity and safety in Rat and Pig. Ultrasound Med Biol 2020; 46:3339-3352. [PMID: 33008649 DOI: 10.1016/j.ultrasmedbio.2020.07.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/24/2020] [Accepted: 07/30/2020] [Indexed: 05/21/2023]
Abstract
Recent advances in the field of monodisperse microbubble synthesis by flow focusing allow for the production of foam-free, highly concentrated and monodisperse lipid-coated microbubble suspensions. It has been found that in vitro, such monodisperse ultrasound contrast agents (UCAs) improve the sensitivity of contrast-enhanced ultrasound imaging. Here, we present the first in vivo study in the left ventricle of rat and pig with this new monodisperse bubble agent. We systematically characterize the acoustic sensitivity and safety of the agent at an imaging frequency of 2.5 MHz as compared with three commercial polydisperse UCAs (SonoVue/Lumason, Definity/Luminity and Optison) and one research-grade polydisperse agent with the same shell composition as the monodisperse bubbles. The monodisperse microbubbles, which had a diameter of 4.2 μm, crossed the pulmonary vasculature, and their echo signal could be measured at least as long as that of the polydisperse UCAs, indicating that microfluidically formed monodisperse microbubbles are stable in vivo. Furthermore, it was found that the sensitivity of the monodisperse agent, expressed as the mean echo power per injected bubble, was at least 10 times higher than that of the polydisperse UCAs. Finally, the safety profile of the monodisperse microbubble suspension was evaluated by injecting 400 and 2000 times the imaging dose, and neither physiologic nor pathologic changes were found, which is a first indication that monodisperse lipid-coated microbubbles formed by flow focusing are safe for in vivo use. The more uniform acoustic response and corresponding increased imaging sensitivity of the monodisperse agent may boost emerging applications of microbubbles and ultrasound such as molecular imaging and therapy.
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Affiliation(s)
- Alexandre Helbert
- Bracco Suisse S.A., Route de la Galaise 31, 1228 Plan-les-Ouates, Switzerland
| | - Emmanuel Gaud
- Bracco Suisse S.A., Route de la Galaise 31, 1228 Plan-les-Ouates, Switzerland
| | - Tim Segers
- Physics of Fluids Group, MESA + Institute for Nanotechnology, Technical Medical (TechMed) Center, University of Twente, Enschede, The Netherlands; Former employee of Bracco Suisse S.A
| | | | | | - Victor Jeannot
- Bracco Suisse S.A., Route de la Galaise 31, 1228 Plan-les-Ouates, Switzerland.
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42
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Helfield BL, Yoo K, Liu J, Williams R, Sheeran PS, Goertz DE, Burns PN. Investigating the Accumulation of Submicron Phase-Change Droplets in Tumors. Ultrasound Med Biol 2020; 46:2861-2870. [PMID: 32732167 DOI: 10.1016/j.ultrasmedbio.2020.06.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 06/24/2020] [Accepted: 06/27/2020] [Indexed: 06/11/2023]
Abstract
Submicron phase-change droplets are an emerging class of ultrasound contrast agent. Compared with microbubbles, their relatively small size and increased stability offer the potential to passively extravasate and accumulate in solid tumors through the enhanced permeability and retention effect. Under exposure to sufficiently powerful ultrasound, these droplets can convert into in situ gas microbubbles and thus be used as an extravascular-specific contrast agent. However, in vivo imaging methods to detect extravasated droplets have yet to be established. Here, we develop an ultrasound imaging pulse sequence within diagnostic safety limits to selectively detect droplet extravasation in tumors. Tumor-bearing mice were injected with submicron perfluorobutane droplets and interrogated with our imaging-vaporization-imaging sequence. By use of a pulse subtraction method, median droplet extravasation signal relative to the total signal within the tumor was estimated to be Etumor=37±5% compared with the kidney Ekidney=-2±8% (p < 0.001). This work contributes toward the advancement of volatile phase-shift droplets as a next-generation ultrasound agent for imaging and therapy.
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Affiliation(s)
- Brandon L Helfield
- Department of Physics, Concordia University, Montreal, Canada; Department of Biology, Concordia University, Montreal, Canada.
| | - Kimoon Yoo
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada
| | - Jingjing Liu
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada
| | - Ross Williams
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada
| | - Paul S Sheeran
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - David E Goertz
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Peter N Burns
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
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43
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Versluis M, Stride E, Lajoinie G, Dollet B, Segers T. Ultrasound Contrast Agent Modeling: A Review. Ultrasound Med Biol 2020; 46:2117-2144. [PMID: 32546411 DOI: 10.1016/j.ultrasmedbio.2020.04.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/11/2020] [Accepted: 04/14/2020] [Indexed: 05/21/2023]
Abstract
Ultrasound is extensively used in medical imaging, being safe and inexpensive and operating in real time. Its scope of applications has been widely broadened by the use of ultrasound contrast agents (UCAs) in the form of microscopic bubbles coated by a biocompatible shell. Their increased use has motivated a large amount of research to understand and characterize their physical properties as well as their interaction with the ultrasound field and their surrounding environment. Here we review the theoretical models that have been proposed to study and predict the behavior of UCAs. We begin with a brief introduction on the development of UCAs. We then present the basics of free-gas-bubble dynamics upon which UCA modeling is based. We review extensively the linear and non-linear models for shell elasticity and viscosity and present models for non-spherical and asymmetric bubble oscillations, especially in the presence of surrounding walls or tissue. Then, higher-order effects such as microstreaming, shedding and acoustic radiation forces are considered. We conclude this review with promising directions for the modeling and development of novel agents.
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Affiliation(s)
- Michel Versluis
- Physics of Fluids Group, MESA+ Institute for Nanotechnology, Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands.
| | - Eleanor Stride
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, UK
| | - Guillaume Lajoinie
- Physics of Fluids Group, MESA+ Institute for Nanotechnology, Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands
| | - Benjamin Dollet
- Centre National de la Recherche Scientifique (CNRS), Laboratoire Interdisciplinaire de Physique (LIPhy), Université Grenoble Alpes, Grenoble, France
| | - Tim Segers
- Physics of Fluids Group, MESA+ Institute for Nanotechnology, Technical Medical (TechMed) Center, University of Twente, Enschede, the Netherlands
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44
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Como G, Da Re J, Adani GL, Zuiani C, Girometti R. Role for contrast-enhanced ultrasound in assessing complications after kidney transplant. World J Radiol 2020; 12:156-171. [PMID: 32913562 PMCID: PMC7457161 DOI: 10.4329/wjr.v12.i8.156] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/30/2020] [Accepted: 07/18/2020] [Indexed: 02/06/2023] Open
Abstract
Kidney transplantation (KT) is an effective treatment for end-stage renal disease. Despite their rate has reduced over time, post-transplant complications still represent a major clinical problem because of the associated risk of graft failure and loss. Thus, post-KT complications should be diagnosed and treated promptly. Imaging plays a pivotal role in this setting. Grayscale ultrasound (US) with color Doppler analysis is the first-line imaging modality for assessing complications, although many findings lack specificity. When performed by experienced operators, contrast-enhanced US (CEUS) has been advocated as a safe and fast tool to improve the accuracy of US. Also, when performing CEUS there is potentially no need for further imaging, such as contrast-enhanced computed tomography or magnetic resonance imaging, which are often contraindicated in recipients with impaired renal function. This technique is also portable to patients' bedside, thus having the potential of maximizing the cost-effectiveness of the whole diagnostic process. Finally, the use of blood-pool contrast agents allows translating information on graft microvasculature into time-intensity curves, and in turn quantitative perfusion indexes. Quantitative analysis is under evaluation as a tool to diagnose rejection or other causes of graft dysfunction. In this paper, we review and illustrate the indications to CEUS in the post-KT setting, as well as the main CEUS findings that can help establishing the diagnosis and planning the most adequate treatment.
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Affiliation(s)
- Giuseppe Como
- Institute of Radiology, University Hospital S. Maria della Misericordia, Udine 33100, Italy
| | - Jacopo Da Re
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine 33100, Italy
| | - Gian Luigi Adani
- Department of Medicine, General Surgery and Transplantation, University Hospital S. Maria della Misericordia, Udine 33100, Italy
| | - Chiara Zuiani
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine 33100, Italy
| | - Rossano Girometti
- Institute of Radiology, Department of Medicine, University of Udine, University Hospital S. Maria della Misericordia, Udine 33100, Italy
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Liang Y, Yang H, Li Q, Zhao P, Li H, Zhang Y, Cai W, Ma X, Duan Y. Novel biomimetic dual-mode nanodroplets as ultrasound contrast agents with potential ability of precise detection and photothermal ablation of tumors. Cancer Chemother Pharmacol 2020; 86:405-418. [PMID: 32797251 DOI: 10.1007/s00280-020-04124-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/04/2020] [Indexed: 01/20/2023]
Abstract
PURPOSE Molecule-targeted ultrasound imaging has attracted extensive attention for precise diagnosis and targeted therapy of tumors. The aim of this research is to prepare novel biomimetic dual-mode nanoscale ultrasound contrast agents (UCAs), which can not only evade the immune clearance of reticuloendothelial system, but also have the potential ability of precise detection and photothermal ablation of tumors. METHODS In this study, for the first time, the novel biomimetic UCAs were prepared by encapsulating liquid perfluorohexanes with red blood cell membranes carrying IR-780 iodide and named IR780-RBCM@NDs. The characteristics of that were verified through the particle size analyzer, scanning electron microscopy, transmission electron microscopy and laser scanning confocal microscopy. The stability of IR780-RBCM@NDs at 37 °C was explored. The abilities of immune escape, dual-mode imaging and photothermal effect for IR780-RBCM@NDs were verified via in vitro experiments. RESULTS The novel prepared nanodroplets have good characteristics such as mean diameter, zeta potential, and relatively stability. Importantly, the integrin-associated protein expressed on the surface of RBCMs was detected on IR780-RBCM@NDs. Then, compared with control groups, IR780-RBCM@NDs performed excellent immune escape function away from macrophages in vitro. Furthermore, the IR-780 iodide was observed on the new nanodroplets and that was able to perform the dual-mode imaging with near-infrared fluorescence imaging and contrast-enhanced ultrasound imaging after the phase change. Finally, the effective photothermal ablation ability of IR780-RBCM@NDs was verified in tumor cells. CONCLUSION The newly prepared biomimetic IR780-RBCM@NDs provided novel ideas for evading immune clearance, performing precise diagnosis and photothermal ablation of tumor cells.
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Affiliation(s)
- Yuan Liang
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Hengli Yang
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Xi'an Medical College, Xi'an, China.
| | - Qiaoying Li
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Ping Zhao
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Han Li
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Yuxin Zhang
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Wenbin Cai
- Special Diagnosis Department, General Hospital of Tibet Military Command, Lhasa, China
| | - Xiaoju Ma
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Yunyou Duan
- Department of Ultrasound Diagnosis, The Second Affiliated Hospital, Air Force Medical University, Xi'an, China.
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46
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Sridharan A, Eisenbrey JR, Stanczak M, Machado P, Merton DA, Wilkes A, Sevrukov A, Ojeda-Fournier H, Mattrey RF, Wallace K, Forsberg F. Characterizing Breast Lesions Using Quantitative Parametric 3D Subharmonic Imaging: A Multicenter Study. Acad Radiol 2020; 27:1065-1074. [PMID: 31859210 DOI: 10.1016/j.acra.2019.10.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 10/16/2019] [Accepted: 10/30/2019] [Indexed: 01/08/2023]
Abstract
RATIONALE AND OBJECTIVES Breast cancer is the leading type of cancer among women. Visualization and characterization of breast lesions based on vascularity kinetics was evaluated using three-dimensional (3D) contrast-enhanced ultrasound imaging in a clinical study. MATERIALS AND METHODS Breast lesions (n = 219) were imaged using power Doppler imaging (PDI), 3D contrast-enhanced harmonic imaging (HI), and 3D contrast-enhanced subharmonic imaging (SHI) with a modified Logiq 9 ultrasound scanner using a 4D10L transducer. Quantitative metrics of vascularity derived from 3D parametric volumes (based on contrast perfusion; PER and area under the curve; AUC) were generated by off-line processing of contrast wash-in and wash-out. Diagnostic accuracy of these quantitative vascular parameters was assessed with biopsy results as the reference standard. RESULTS Vascularity was observed with PDI in 93 lesions (69 benign and 24 malignant), 3D HI in 8 lesions (5 benign and 3 malignant), and 3D SHI in 83 lesions (58 benign and 25 malignant). Diagnostic accuracy for vascular heterogeneity, PER, and AUC ranged from 0.52 to 0.75, while the best logistical regression model (vascular heterogeneity ratio, central PER, and central AUC) reached 0.90. CONCLUSION 3D SHI successfully detects contrast agent flow in breast lesions and characterization of these lesions based on quantitative measures of vascular heterogeneity and 3D parametric volumes is promising.
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Affiliation(s)
- Anush Sridharan
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107; Department of Electrical and Computer Engineering, Drexel University, Philadelphia, Pennsylvania
| | - John R Eisenbrey
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | - Maria Stanczak
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | - Priscilla Machado
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | - Daniel A Merton
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | - Annina Wilkes
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | - Alexander Sevrukov
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107
| | | | - Robert F Mattrey
- Department of Radiology, University of California, San Diego, California
| | | | - Flemming Forsberg
- Department of Radiology, Thomas Jefferson University, 763H Main Building, 132 South 10th Street, Philadelphia, PA 19107.
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47
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Osborn J, Pullan JE, Froberg J, Shreffler J, Gange KN, Molden T, Choi Y, Brooks A, Mallik S, Sarkar K. Echogenic Exosomes as ultrasound contrast agents. Nanoscale Adv 2020; 2:3411-3422. [PMID: 36034734 PMCID: PMC9410358 DOI: 10.1039/d0na00339e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/15/2020] [Indexed: 05/19/2023]
Abstract
Exosomes are naturally secreted extracellular bilayer vesicles (diameter 40-130 nm), which have recently been found to play a critical role in cell-to-cell communication and biomolecule delivery. Their unique characteristics-stability, permeability, biocompatibility and low immunogenicity-have made them a prime candidate for use in delivering cancer therapeutics and other natural products. Here we present the first ever report of echogenic exosomes, which combine the benefits of the acoustic responsiveness of traditional microbubbles with the non-immunogenic and small-size morphology of exosomes. Microbubbles, although effective as ultrasound contrast agents, are restricted to intravascular usage due to their large size. In the current study, we have rendered bovine milk-derived exosomes echogenic by freeze drying them in the presence of mannitol. Ultrasound imaging and direct measurement of linear and nonlinear scattered responses were used to investigate the echogenicity and stability of the prepared exosomes. A commercial scanner registered enhancement (28.9% at 40 MHz) in the brightness of ultrasound images in presence of echogenic exosomes at 5 mg/mL. The exosomes also showed significant linear and nonlinear scattered responses-11 dB enhancement in fundamental, 8.5 dB in subharmonic and 3.5 dB in second harmonic all at 40 μg/mL concentration. Echogenic exosomes injected into the tail vein of mice and the synovial fluid of rats resulted in significantly higher brightness-as much as 300%-of the ultrasound images, showing their promise in a variety of in vivo applications. The echogenic exosomes, with their large-scale extractability from bovine milk, lack of toxicity and minimal immunogenic response, successfully served as ultrasound contrast agents in this study and offer an exciting possibility to act as an effective ultrasound responsive drug delivery system.
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Affiliation(s)
- Jenna Osborn
- Mechanical and Aerospace Engineering, George Washington UniversityWashington DC 20052USA
| | - Jessica E. Pullan
- Pharmaceutical Sciences, North Dakota State UniversityFargoND 58105USA
| | - James Froberg
- Physics, North Dakota State UniversityFargoND 58105USA
| | - Jacob Shreffler
- Pharmaceutical Sciences, North Dakota State UniversityFargoND 58105USA
| | - Kara N. Gange
- Health, Nutrition, and Exercise Science, North Dakota State UniversityFargoND 58105USA
| | - Todd Molden
- Animal Science, North Dakota State UniversityFargoND 58105USA
| | - Yongki Choi
- Physics, North Dakota State UniversityFargoND 58105USA
| | - Amanda Brooks
- Pharmaceutical Sciences, North Dakota State UniversityFargoND 58105USA
| | - Sanku Mallik
- Pharmaceutical Sciences, North Dakota State UniversityFargoND 58105USA
| | - Kausik Sarkar
- Mechanical and Aerospace Engineering, George Washington UniversityWashington DC 20052USA
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Al-Jawadi S, Thakur SS. Ultrasound-responsive lipid microbubbles for drug delivery: A review of preparation techniques to optimise formulation size, stability and drug loading. Int J Pharm 2020; 585:119559. [PMID: 32574685 DOI: 10.1016/j.ijpharm.2020.119559] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 02/08/2023]
Abstract
Lipid-shelled microbubbles have received extensive interest to enhance ultrasound-responsive drug delivery outcomes due to their high biocompatibility. While therapeutic effectiveness of microbubbles is well established, there remain limitations in sample homogeneity, stability profile and drug loading properties which restrict these formulations from seeing widespread use in the clinical setting. In this review, we evaluate and discuss the most encouraging leads in lipid microbubble design and optimisation. We examine current applications in drug delivery for the systems and subsequently detail shell compositions and preparation strategies that improve monodispersity while retaining ultrasound responsiveness. We review how excipients and storage techniques help maximise stability and introduce different characterisation and drug loading techniques and evaluate their impact on formulation performance. The review concludes with current quality control measures in place to ensure lipid microbubbles can be reproducibly used in drug delivery.
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Affiliation(s)
- Sana Al-Jawadi
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Sachin S Thakur
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
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49
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Stride E, Segers T, Lajoinie G, Cherkaoui S, Bettinger T, Versluis M, Borden M. Microbubble Agents: New Directions. Ultrasound Med Biol 2020; 46:1326-1343. [PMID: 32169397 DOI: 10.1016/j.ultrasmedbio.2020.01.027] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/09/2020] [Accepted: 01/26/2020] [Indexed: 05/24/2023]
Abstract
Microbubble ultrasound contrast agents have now been in use for several decades and their safety and efficacy in a wide range of diagnostic applications have been well established. Recent progress in imaging technology is facilitating exciting developments in techniques such as molecular, 3-D and super resolution imaging and new agents are now being developed to meet their specific requirements. In parallel, there have been significant advances in the therapeutic applications of microbubbles, with recent clinical trials demonstrating drug delivery across the blood-brain barrier and into solid tumours. New agents are similarly being tailored toward these applications, including nanoscale microbubble precursors offering superior circulation times and tissue penetration. The development of novel agents does, however, present several challenges, particularly regarding the regulatory framework. This article reviews the developments in agents for diagnostic, therapeutic and "theranostic" applications; novel manufacturing techniques; and the opportunities and challenges for their commercial and clinical translation.
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Affiliation(s)
- Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK.
| | - Tim Segers
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Guillaume Lajoinie
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Samir Cherkaoui
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Thierry Bettinger
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Michel Versluis
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Mark Borden
- Mechanical Engineering Department, University of Colorado, Boulder, CO, USA
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50
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Fischer C, Krix M, Weber MA, Loizides A, Gruber H, Jung EM, Klauser A, Radzina M, Dietrich CF. Contrast-Enhanced Ultrasound for Musculoskeletal Applications: A World Federation for Ultrasound in Medicine and Biology Position Paper. Ultrasound Med Biol 2020; 46:1279-1295. [PMID: 32139152 DOI: 10.1016/j.ultrasmedbio.2020.01.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 06/10/2023]
Abstract
This World Federation for Ultrasound in Medicine and Biology position paper reviews the diagnostic potential of ultrasound contrast agents for clinical decision-making and provides general advice for optimal contrast-enhanced ultrasound performance in musculoskeletal issues. In this domain, contrast-enhanced ultrasound performance has increasingly been investigated with promising results, but still lacks everyday clinical application and standardized techniques; therefore, experts summarized current knowledge according to published evidence and best personal experience. The goal was to intensify and standardize the use and administration of ultrasound contrast agents to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients.
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Affiliation(s)
- Christian Fischer
- Center for Orthopaedics, Trauma Surgery and Spinal Cord Injury, Ultrasound Center, HTRG-Heidelberg Trauma Research Group, Heidelberg University Hospital, Heidelberg, Germany.
| | | | - Marc-André Weber
- Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, University Medical Center Rostock, Rostock, Germany
| | - Alexander Loizides
- Department of Radiology, Ultrasound Center, Innsbruck Medical University, Innsbruck, Austria
| | - Hannes Gruber
- Department of Radiology, Ultrasound Center, Innsbruck Medical University, Innsbruck, Austria
| | | | - Andrea Klauser
- Department of Radiology, Ultrasound Center, Innsbruck Medical University, Innsbruck, Austria
| | - Maija Radzina
- Diagnostic Radiology Institute, Riga Stradins University, Riga, Latvia
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