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Soloukey S, Generowicz B, Warnert E, Springeling G, Schouten J, De Zeeuw C, Dirven C, Vincent A, Kruizinga P. Patient-Specific Vascular Flow Phantom for MRI- and Doppler Ultrasound Imaging. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:860-868. [PMID: 38471997 DOI: 10.1016/j.ultrasmedbio.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/29/2024] [Accepted: 02/16/2024] [Indexed: 03/14/2024]
Abstract
OBJECTIVE Intraoperative Doppler ultrasound imaging of human brain vasculature is an emerging neuro-imaging modality that offers vascular brain mapping with unprecedented spatiotemporal resolution. At present, however, access to the human brain using Doppler Ultrasound is only possible in this intraoperative context, posing a significant challenge for validation of imaging techniques. This challenge necessitates the development of realistic flow phantoms outside of the neurosurgical operating room as external platforms for testing hardware and software. An ideal ultrasound flow phantom should provide reference-like values in standardized topologies such as a slanted pipe, and allow for measurements in structures closely resembling vascular morphology of actual patients. Additionally, the phantom should be compatible with other clinical cerebrovascular imaging modalities. To meet these criteria, we developed and validated a versatile, multimodal MRI- and ultrasound Doppler phantom. METHODS Our approach incorporates the latest advancements in phantom research using tissue-mimicking material and 3D-printing with water-soluble resin to create wall-less patient-specific lumens, compatible for ultrasound and MRI. RESULTS We successfully produced three distinct phantoms: a slanted pipe, a y-shape phantom representing a bifurcating vessel and an arteriovenous malformation (AVM) derived from clinical Digital Subtraction Angiography (DSA)-data of the brain. We present 3D ultrafast power Doppler imaging results from these phantoms, demonstrating their ability to mimic complex flow patterns as observed in the human brain. Furthermore, we showcase the compatibility of our phantom with Magnetic Resonance Imaging (MRI). CONCLUSION We developed an MRI- and Doppler Ultrasound-compatible flow-phantom using customizable, water-soluble resin prints ranging from geometrical forms to patient-specific vasculature.
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Affiliation(s)
- Sadaf Soloukey
- Department of Neuroscience, Erasmus MC, Rotterdam, The Netherlands; Department of Neurosurgery, Erasmus MC, Rotterdam, The Netherlands.
| | | | - Esther Warnert
- Deparment of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands; Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Geert Springeling
- Deparment of Experimental Medical Instrumentation, Erasmus MC, Rotterdam, The Netherlands
| | - Joost Schouten
- Department of Neurosurgery, Erasmus MC, Rotterdam, The Netherlands
| | - Chris De Zeeuw
- Department of Neuroscience, Erasmus MC, Rotterdam, The Netherlands; Netherlands Institute for Neuroscience, Royal Dutch Academy for Arts and Sciences, Amsterdam, Netherlands
| | - Clemens Dirven
- Department of Neurosurgery, Erasmus MC, Rotterdam, The Netherlands
| | - Arnaud Vincent
- Department of Neurosurgery, Erasmus MC, Rotterdam, The Netherlands
| | - Pieter Kruizinga
- Department of Neuroscience, Erasmus MC, Rotterdam, The Netherlands
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Grasso V, Raymond JL, Willumeit-Römer R, Joseph J, Jose J. Development of a morphologically realistic mouse phantom for pre-clinical photoacoustic imaging. Med Phys 2023; 50:5757-5771. [PMID: 37535898 DOI: 10.1002/mp.16651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 07/10/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Characterizations based on anatomically realistic phantoms are highly effective to perform accurate technical validation of imaging systems. Specifically for photoacoustic imaging (PAI), although a variety of phantom models with simplified geometries are reported, an unmet need still exists to establish morphologically realistic heterogeneous pre-clinical phantoms. So the development of a mouse-mimicking phantom can reduce the use of animals for the validation and standardization studies of pre-clinical PAI systems and thus eventually translate the PAI technology to clinical research. PURPOSE Here we designed, developed, and fabricated a stable phantom that mimics the detailed morphology of a mouse, to be used as a realistic tool for PAI. METHODS The mouse phantom, has been designed by using a combination of image modeling and 3D-printing techniques. As a tissue-mimicking material, we have used copolymer-in-oil-based material that was recently proposed by the International Photoacoustic Standardization Consortium (IPASC). In particular, the anatomically realistic phantom has been modeled by using the real atlas of a mouse as a reference. The mouse phantom includes a 3D-printed skeleton and the main abdominal organs such as the liver, spleen, and kidneys obtained by using doped copolymer-in-oil material with 3D-printed molds. In addition, the acoustic and optical properties of the tissue-mimicking material and the long-term stability have been broadly characterized. RESULTS Furthermore, our studies showed that the phantom is durable and stable for more than 200 days, under normal storage and repeated use. Fabrication protocol is easy to reproduce. As a result, the proposed morphologically realistic mouse phantom offers durability, material compatibility, and an unprecedented realistic resemblance to the actual rodents' anatomy in PAI. CONCLUSION This durable morphologically realistic mouse phantom would minimize the animal experiments in compliance with the 3R principle of Replacement, Reduction, and Refinement. To our knowledge, this is the first time an anatomically realistic heterogeneous mouse phantom has been proposed for PAI in pre-clinical animal imaging and tested its durability over 200 days.
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Affiliation(s)
- Valeria Grasso
- FUJIFILM VisualSonics, Amsterdam, The Netherlands
- Institute for Materials Science, Faculty of Engineering, Christian-Albrecht University of Kiel, Kiel, Germany
| | - Jason L Raymond
- Department of Engineering Science, University of Oxford, Oxford, UK
| | - Regine Willumeit-Römer
- Institute for Materials Science, Faculty of Engineering, Christian-Albrecht University of Kiel, Kiel, Germany
- Institute of Materials Research, Division Metallic Biomaterials, Helmholtz-Zentrum Hereon GmbH, Geesthacht, Germany
| | - James Joseph
- School of Science and Engineering, University of Dundee, Dundee, UK
- Centre for Medical Engineering and Technology, University of Dundee, Dundee, UK
| | - Jithin Jose
- FUJIFILM VisualSonics, Amsterdam, The Netherlands
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Microbubbles for human diagnosis and therapy. Biomaterials 2023; 294:122025. [PMID: 36716588 DOI: 10.1016/j.biomaterials.2023.122025] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/17/2023] [Accepted: 01/24/2023] [Indexed: 01/26/2023]
Abstract
Microbubbles (MBs) were observed for the first time in vivo as a curious consequence of quick saline injection during ultrasound (US) imaging of the aortic root, more than 50 years ago. From this serendipitous event, MBs are now widely used as contrast enhancers for US imaging. Their intrinsic properties described in this review, allow a multitude of designs, from shell to gas composition but also from grafting targeting agents to drug payload encapsulation. Indeed, the versatile MBs are deeply studied for their dual potential in imaging and therapy. As presented in this paper, new generations of MBs now opens perspectives for targeted molecular imaging along with the development of new US imaging systems. This review also presents an overview of the different therapeutic strategies with US and MBs for cancer, cardiovascular diseases, and inflammation. The overall aim is to overlap those fields in order to find similarities in the MBs application for treatment enhancement associated with US. To conclude, this review explores the new scales of MBs technologies with nanobubbles development, and along concurrent advances in the US imaging field. This review ends by discussing perspectives for the booming future uses of MBs.
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Arteaga-Marrero N, Villa E, Llanos González AB, Gómez Gil ME, Fernández OA, Ruiz-Alzola J, González-Fernández J. Low-Cost Pseudo-Anthropomorphic PVA-C and Cellulose Lung Phantom for Ultrasound-Guided Interventions. Gels 2023; 9:gels9020074. [PMID: 36826245 PMCID: PMC9957311 DOI: 10.3390/gels9020074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
A low-cost custom-made pseudo-anthropomorphic lung phantom, offering a model for ultrasound-guided interventions, is presented. The phantom is a rectangular solidstructure fabricated with polyvinyl alcohol cryogel (PVA-C) and cellulose to mimic the healthy parenchyma. The pathologies of interest were embedded as inclusions containing gaseous, liquid, or solid materials. The ribs were 3D-printed using polyethylene terephthalate, and the pleura was made of a bidimensional reticle based on PVA-C. The healthy and pathological tissues were mimicked to display acoustic and echoic properties similar to that of soft tissues. Theflexible fabrication process facilitated the modification of the physical and acoustic properties of the phantom. The phantom's manufacture offers flexibility regarding the number, shape, location, and composition of the inclusions and the insertion of ribs and pleura. In-plane and out-of-plane needle insertions, fine needle aspiration, and core needle biopsy were performed under ultrasound image guidance. The mimicked tissues displayed a resistance and recoil effect typically encountered in a real scenario for a pneumothorax, abscesses, and neoplasms. The presented phantom accurately replicated thoracic tissues (lung, ribs, and pleura) and associated pathologies providing a useful tool for training ultrasound-guided procedures.
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Affiliation(s)
- Natalia Arteaga-Marrero
- Grupo Tecnología Médica IACTEC, Instituto de Astrofísica de Canarias (IAC), 38205 San Cristóbal de La Laguna, Spain
| | - Enrique Villa
- Grupo Tecnología Médica IACTEC, Instituto de Astrofísica de Canarias (IAC), 38205 San Cristóbal de La Laguna, Spain
- Correspondence:
| | - Ana Belén Llanos González
- Departamento de Neumología, Complejo Universitario de Canarias (HUC), 38320 San Cristóbal de La Laguna, Spain
| | - Marta Elena Gómez Gil
- Departameto de Radiología, Complejo Universitario de Canarias (HUC), 38320 San Cristóbal de La Laguna, Spain
| | - Orlando Acosta Fernández
- Departamento de Neumología, Complejo Universitario de Canarias (HUC), 38320 San Cristóbal de La Laguna, Spain
| | - Juan Ruiz-Alzola
- Grupo Tecnología Médica IACTEC, Instituto de Astrofísica de Canarias (IAC), 38205 San Cristóbal de La Laguna, Spain
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS), Universidad de Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
- Departamento de Señales y Comunicaciones, Universidad de Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
| | - Javier González-Fernández
- Departamento de Ingeniería Biomédica, Instituto Tecnológico de Canarias (ITC), 38009 Santa Cruz de Tenerife, Spain
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Hacker L, Joseph J, Ivory AM, Saed MO, Zeqiri B, Rajagopal S, Bohndiek SE. A Copolymer-in-Oil Tissue-Mimicking Material With Tuneable Acoustic and Optical Characteristics for Photoacoustic Imaging Phantoms. IEEE TRANSACTIONS ON MEDICAL IMAGING 2021; 40:3593-3603. [PMID: 34152979 DOI: 10.1109/tmi.2021.3090857] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Photoacoustic imaging (PAI) standardisation demands a stable, highly reproducible physical phantom to enable routine quality control and robust performance evaluation. To address this need, we have optimised a low-cost copolymer-in-oil tissue-mimickingmaterial formulation. The base material consists of mineral oil, copolymer and stabiliser with defined Chemical Abstract Service numbers. Speed of sound c(f) and acoustic attenuation coefficient α (f) were characterised over 2-10 MHz; optical absorption μa ( λ ) and reduced scattering μs '( λ ) coefficients over 450-900 nm. Acoustic properties were optimised by modifying base component ratios and optical properties were adjusted using additives. The temporal, thermomechanical and photo-stabilitywere studied, alongwith intra-laboratory fabrication and field-testing. c(f) could be tuned up to (1516±0.6) [Formula: see text] and α (f) to (17.4±0.3)dB · cm -1 at 5 MHz. The base material exhibited negligible μa ( λ ) and μs '( λ ), which could be independently tuned by addition of Nigrosin or TiO2 respectively. These properties were stable over almost a year and were minimally affected by recasting. The material showed high intra-laboratory reproducibility (coefficient of variation <4% for c ( f ), α ( f ), optical transmittance and reflectance), and good photo- and mechanical-stability in the relevant working range (20-40°C). The optimised copolymer-in-oil material represents an excellent candidate for widespread application in PAI phantoms, with properties suitable for broader use in biophotonics and ultrasound imaging standardisation efforts.
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Dantuma M, Kruitwagen SC, Weggemans MJ, Op’t Root TJPM, Manohar S. Suite of 3D test objects for performance assessment of hybrid photoacoustic-ultrasound breast imaging systems. JOURNAL OF BIOMEDICAL OPTICS 2021; 27:JBO-210239SSR. [PMID: 34889084 PMCID: PMC8655513 DOI: 10.1117/1.jbo.27.7.074709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
SIGNIFICANCE During the development and early testing phases of new photoacoustic (PA) breast imaging systems, several choices need to be made in aspects of system design and measurement sequences. Decision-making can be complex for state-of-the-art systems such as 3D hybrid photoacoustic-ultrasound (PA-US) breast imagers intended for multispectral quantitative imaging. These systems have a large set of design choices and system settings that affect imaging performance in different ways and often require trade-offs. Decisions have to be made carefully as they can strongly influence the imaging performance. AIM A systematic approach to assess the influence of various choices on the imaging performance in carefully controlled laboratory situations is crucial before starting with human studies. Test objects and phantoms are used for first imaging studies, but most reported structures have a 2D geometry and are not suitable to assess all the image quality characteristics (IQCs) of 3D hybrid PA-US systems. APPROACH Our work introduces a suite of five test objects designed for hybrid PA-US systems with a 3D detection aperture. We present the test object designs and production protocols and explain how they can be used to study various performance measures. To demonstrate the utility of the developed objects, measurements are made with an existing tomographic PA system. RESULTS Two test objects were developed for measurements of the US detectors' impulse responses and light distribution on the breast surface. Three others were developed to assess image quality and quantitative accuracy of the PA and US modes. Three of the five objects were imaged to demonstrate their use. CONCLUSIONS The developed test objects allow one to study influences of various choices in design and system settings. With this, IQCs can be assessed as a function of measurement sequence settings for the PA and US modes in a controlled way. Systematic studies and measurements using these objects will help to optimize various system settings and measurement protocols in laboratory situations before embarking on human studies.
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Affiliation(s)
- Maura Dantuma
- University of Twente, Multi-Modality Medical Imaging, Technical Medical Centre, Enschede, The Netherlands
| | - Saskia C. Kruitwagen
- University of Twente, Multi-Modality Medical Imaging, Technical Medical Centre, Enschede, The Netherlands
- Medisch Spectrum Twente Hospital, Enschede, The Netherlands
| | - Marlies J. Weggemans
- University of Twente, Multi-Modality Medical Imaging, Technical Medical Centre, Enschede, The Netherlands
| | | | - Srirang Manohar
- University of Twente, Multi-Modality Medical Imaging, Technical Medical Centre, Enschede, The Netherlands
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Najaf Zadeh H, Bowles D, Huber T, Clucas D. A Novel Additive Manufacturing Method of Cellulose Gel. MATERIALS 2021; 14:ma14226988. [PMID: 34832391 PMCID: PMC8621294 DOI: 10.3390/ma14226988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/08/2021] [Accepted: 11/12/2021] [Indexed: 01/25/2023]
Abstract
Screen-additive manufacturing (SAM) is a potential method for producing small intricate parts without waste generation, offering minimal production cost. A wide range of materials, including gels, can be shaped using this method. A gel material is composed of a three-dimensional cross-linked polymer or colloidal network immersed in a fluid, known as hydrogel when its main constituent fluid is water. Hydrogels are capable of absorbing and retaining large amounts of water. Cellulose gel is among the materials that can form hydrogels and, as shown in this work, has the required properties to be directly SAM, including shear thinning and formation of post-shearing gel structure. In this study, we present the developed method of SAM for the fabrication of complex-shaped cellulose gel and examine whether successive printing layers can be completed without delamination. In addition, we evaluated cellulose SAM without the need for support material. Design of Experiments (DoE) was applied to optimize the SAM settings for printing the novel cellulose-based gel structure. The optimum print settings were then used to print a periodic structure with micro features and without the need for support material.
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Affiliation(s)
- Hossein Najaf Zadeh
- College of Engineering, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand; (D.B.); (D.C.)
- Biomolecular Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand;
- Correspondence:
| | - Daniel Bowles
- College of Engineering, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand; (D.B.); (D.C.)
| | - Tim Huber
- Biomolecular Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand;
- School of Product Design, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand
| | - Don Clucas
- College of Engineering, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand; (D.B.); (D.C.)
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Cabrelli LC, Uliana JH, da Cruz Junior LB, Bachmann L, Carneiro AAO, Pavan TZ. Glycerol-in-SEBS gel as a material to manufacture stable wall-less vascular phantom for ultrasound and photoacoustic imaging. Biomed Phys Eng Express 2021; 7. [PMID: 34496358 DOI: 10.1088/2057-1976/ac24d6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/08/2021] [Indexed: 11/12/2022]
Abstract
Styrene-ethylene/butylene-styrene (SEBS) copolymer-in-mineral oil gel is an appropriate tissue-mimicking material to manufacture stable phantoms for ultrasound and photoacoustic imaging. Glycerol dispersion has been proposed to further tune the acoustic properties and to incorporate hydrophilic additives into SEBS gel. However, this type of material has not been investigated to produce wall-less vascular flow phantom for these imaging modalities. In this paper, the development of a wall-less vascular phantom for ultrasound and photoacoustic imaging is reported. Mixtures of glycerol/TiO2-in-SEBS gel samples were manufactured at different proportions of glycerol (10%, 15%, and 20%) and TiO2(0% to 0.5%) to characterize their optical and acoustic properties. Optical absorption in the 500-950 nm range was independent of the amount of glycerol and TiO2, while optical scattering increased linearly with the concentration of TiO2. Acoustic attenuation and speed of sound were not influenced by the presence of TiO2. The sample manufactured using weight percentages of 10% SEBS, 15% glycerol, and 0.2% TiO2was selected to make the vascular phantom. The phantom proved to be stable during the pulsatile blood-mimicking fluid (BMF) flow, without any observed damage to its structure or leaks. Ultrasound color Doppler images showed a typical laminar flow, while the B-mode images showed a homogeneous speckled pattern due to the presence of the glycerol droplets in the gel. The photoacoustic images of the phantom showed a well-defined signal coming from the surface of the phantom and from the vessels where BMF was flowing. The Spearman's correlations between the photoacoustic and tabulated spectra calculated from the regions containing BMF, in this case a mixture of salt solutions (NiCl2and CuSO4), were higher than 0.95. Our results demonstrated that glycerol-in-SEBS gel was an adequate material to make a stable vascular flow phantom for ultrasound photoacoustic imaging.
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Affiliation(s)
- Luciana C Cabrelli
- Departamento de Física, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Joao H Uliana
- Departamento de Física, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Luciano Bachmann
- Departamento de Física, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Antonio A O Carneiro
- Departamento de Física, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Theo Z Pavan
- Departamento de Física, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
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Abstract
The ultrasound phantoms used to educate medical students should not only closely mimic the ultrasound characteristics of human soft tissues but also be inexpensive and easy to manufacture. I have been studying handmade ultrasound phantoms and proposed an ultrasound phantom comprising calcium alginate hydrogel that met these requirements but caused a speckle pattern similar to that observed in ultrasound images of liver. In this study, I show that adding ethanol to the precursors used to fabricate the phantom reduces the speckle pattern. The ultrasound propagation velocity and attenuation coefficient of the phantom were 1561 ± 8 m/s and 0.54 ± 0.18 dB/cm/MHz, respectively (mean ± standard deviation), which are within the ranges of those in human soft tissues (1530-1600 m/s and 0.3-1.0 dB/cm/MHz, respectively). This phantom is easy to fabricate without special equipment, is inexpensive, and is suitable for elementary training on ultrasound diagnosis, operation of ultrasound-guided needles, and blind catheter insertion.
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Affiliation(s)
- Minoru Aoyagi
- Department of Electrical and Electronics Engineering, Nippon Institute of Technology, Miyashiro, Saitama, Japan
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Mitchell C, Xiong PL, Cox BL, Adoe MA, Cordio MM, Quade TR, Petry G, Eliceiri KW. Evaluating the effectiveness of a lower extremity venous phantom on developing ultrasound examination skills and confidence. ULTRASOUND : JOURNAL OF THE BRITISH MEDICAL ULTRASOUND SOCIETY 2021; 29:18-26. [PMID: 33552224 DOI: 10.1177/1742271x20950777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/21/2020] [Indexed: 11/16/2022]
Abstract
Introduction The aims of this study were: (1) Determine the effect on student ultrasound scanning skills using a lower extremity venous ultrasound phantom in addition to standard teaching methods of didactic lecture and scanning live volunteers and (2) Determine the effect of using a lower extremity venous ultrasound phantom in addition to standard teaching methods of didactic lecture and scanning live volunteers on student confidence levels in performing the lower extremity venous ultrasound examination. Methods Participants were first year diagnostic medical sonography students with minimal scanning experience (n = 11), which were randomized into two groups. Group 1 (n = 5) received the standard didactic lecture and attended a scan lab assessment where they performed a lower extremity venous examination on a human volunteer. Group 2 (n = 6) received the standard didactic lecture, performed three scheduled scanning sessions on an anatomic lower extremity venous phantom with flow and then attended the same scan lab assessment as Group 1, where they performed a lower extremity venous examination on a human volunteer. Results Scan lab assessments on day 4 of the study demonstrated a significant difference in scanning performance (p = 0.019) between the two groups. Post scan lab assessment confidence scores also demonstrated a significant difference between how participants in each group scored their confidence levels (p = 0.0260), especially in the ability to image calf veins. Conclusions This study suggests anatomical phantoms can be used to develop scanning skills and build confidence in ultrasound imaging of the lower extremity venous structures.
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Affiliation(s)
- Carol Mitchell
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI, USA
| | - Pazee L Xiong
- Morgridge Institute for Research, Madison, WI, USA.,Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Benjamin L Cox
- Morgridge Institute for Research, Madison, WI, USA.,Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Maame A Adoe
- University of Wisconsin Hospital and Clinics, Echo/Vascular Lab, Madison, WI, USA
| | - Michelle M Cordio
- Department of Human Resources, University of Wisconsin Hospital and Clinics School of Diagnostic Medical Sonography, Madison, WI, USA.,Department of Radiology, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI, USA
| | - Tonya R Quade
- Department of Human Resources, University of Wisconsin Hospital and Clinics School of Diagnostic Medical Sonography, Madison, WI, USA.,Department of Radiology, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI, USA.,SSM Health, Waupun Memorial Hospital and Ripon Medical Center, Ripon, WI, USA
| | - George Petry
- Morgridge Institute for Research, Madison, WI, USA
| | - Kevin W Eliceiri
- Morgridge Institute for Research, Madison, WI, USA.,Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI, USA.,Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
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Shin KC, Ha YR, Lee SJ, Ahn JH. Review of simulation model for education of point-of-care ultrasound using easy-to-make tools. World J Clin Cases 2020; 8:4286-4302. [PMID: 33083388 PMCID: PMC7559657 DOI: 10.12998/wjcc.v8.i19.4286] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 09/03/2020] [Accepted: 09/11/2020] [Indexed: 02/05/2023] Open
Abstract
Point-of-care ultrasound (POCUS) is a powerful diagnostic tool and provides treatment guidelines in acute critical settings. However, the limitation of using POCUS is operator dependent. Appropriate and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients safe. Simulation education models have been introduced as a way to solve and overcome these concerns. However, the commercial simulator with sufficiently secured fidelity is expensive and not always available. This review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway, breathing, circulation, and disability. We introduced the simulators that used non-infectious materials, with easily transportable features, and that had a sonographic appearance reproducibility similar to human tissue. We also introduced the recipe of each simulator in two parts: Materials surrounding disease simulators (surrounding materials) and specific disease simulators themselves (target simulators). This review article covered the following: endotracheal or oesophageal intubation, lung (A-lines, B-lines, lung sliding, and pleural effusions such as hemothorax), central vein access, pericardial fluid (cardiac tamponade), the structure related to the eyes, soft tissue abscess, nerve (regional nerve block), and skull fracture simulators.
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Affiliation(s)
- Kyu Chul Shin
- Department of Emergency Medicine, Ajou University School of Medicine, Suwon 16499, Gyeonggi-do, South Korea
| | - Young Rock Ha
- Department of Emergency Medicine, Bundang Jesaeng Hospital, Seongnam-si 13590, South Korea
| | - Seong-Joon Lee
- Department of Neurology, Ajou University School of Medicine, Suwon 16499, Gyeonggi-do, South Korea
| | - Jung Hwan Ahn
- Department of Emergency Medicine, Ajou University School of Medicine, Suwon 16499, Gyeonggi-do, South Korea
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Nisar H, Moore J, Piazza R, Maneas E, Chen ECS, Peters TM. A simple, realistic walled phantom for intravascular and intracardiac applications. Int J Comput Assist Radiol Surg 2020; 15:1513-1523. [PMID: 32524216 PMCID: PMC7419379 DOI: 10.1007/s11548-020-02201-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 05/18/2020] [Indexed: 11/29/2022]
Abstract
PURPOSE This work aims to develop a simple, anatomically and haptically realistic vascular phantom, compatible with intravascular and intracardiac ultrasound. The low-cost, dual-layered phantom bridges the gap between traditional wall-only and wall-less phantoms by showing both the vessel wall and surrounding tissue in ultrasound imaging. This phantom can better assist clinical tool training, testing of intravascular devices, blood flow studies, and validation of algorithms for intravascular and intracardiac surgical systems. METHODS Polyvinyl alcohol cryogel (PVA-c) incorporating a scattering agent was used to obtain vessel and tissue-mimicking materials. Our specific design targeted the inferior vena cava and renal bifurcations which were modelled using CAD software. A custom mould and container were 3D-printed for shaping the desired vessel wall. Three phantoms were prepared by varying both the concentrations of scattering agent as well as the number of freeze-thaw cycles to which the phantom layers were subjected during the manufacturing process. Each phantom was evaluated using ultrasound imaging using the Foresight™ ICE probe. Geometrical validation was provided by comparing CAD design to a CT scan of the phantom. RESULTS The desired vascular phantom was constructed using 2.5% and 0.05% scattering agent concentration in the vessel and tissue-mimicking layers, respectively. Imaging of the three phantoms showed that increasing the number of freeze-thaw cycles did not significantly enhance the image contrast. Comparison of the US images with their CT equivalents resulted in an average error of 0.9[Formula: see text] for the lumen diameter. CONCLUSION The phantom is anatomically realistic when imaged with intracardiac ultrasound and provides a smooth lumen for the ultrasound probe and catheter to manoeuvre. The vascular phantom enables validation of intravascular and intracardiac image guidance systems. The simple construction technique also provides a workflow for designing complex, multi-layered arterial phantoms.
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Affiliation(s)
- Hareem Nisar
- Robarts Research Institute, Western University, London, Canada. .,School of Biomedical Engineering, Western University, London, Canada.
| | - John Moore
- Robarts Research Institute, Western University, London, Canada
| | - Roberta Piazza
- Department of Information Engineering, University of Pisa, Pisa, Italy
| | - Efthymios Maneas
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, UK.,Department of Medical Physics and Bioengineering, University College London, London, UK
| | - Elvis C S Chen
- Robarts Research Institute, Western University, London, Canada.,School of Biomedical Engineering, Western University, London, Canada.,Department of Medical Biophysics, Western University, London, Canada
| | - Terry M Peters
- Robarts Research Institute, Western University, London, Canada.,School of Biomedical Engineering, Western University, London, Canada.,Department of Medical Biophysics, Western University, London, Canada.,Department of Medical Imaging, Western University, London, Canada
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Headman ZC, Matson MC, Schneider RP, Potter JL, Loguda-Summers DL, Bhatia S, Kondrashova T. Developing Neuraxial and Regional Pain Procedural Skills Through Innovative 3-Dimensional Printing Technology. J Osteopath Med 2020; 120:273-282. [DOI: 10.7556/jaoa.2020.044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Context
Various forms of simulation-based training, including training models, increase training opportunities and help assess performance of a task. However, commercial training models for lumbar puncture and epidural procedures are costly.
Objective
To assess medical students’ and residents’ perception of 3-dimensional (3D)-printed lumbar, cervical, and pelvic models for mastering joint injection techniques and to determine the utility of ultrasonography-guided needle procedure training.
Methods
Osteopathic medical students and residents used in-house 3D-printed gel joint models during an injection ultrasonography laboratory for mastering lumbar epidural, caudal epidural, sacroiliac, and facet joint injection techniques. After the laboratory, they answered a 17-item survey about their perception of the importance of the models in medical education and future practice. The survey also evaluated comfort levels with performing joint injections after using the models, overall satisfaction with the models, and likelihood of using models in the future.
Results
Thirty-six medical students and residents participated. Both students and residents agreed that 3D-printed models were easy to use, aided understanding of corresponding procedures, and increased comfort with performing joint injections (all P<.001). Most participants (35 [97.2%]) believed that the models were reasonable alternatives to commercial models. Over half felt capable of successfully performing cervical or pelvic (22 [61.1%]) and lumbar epidural (23 [63.9%]) injections. The majority of participants (34 [94.4%]) would like to use the models in the future for personal training purposes. Overall, 100% believed that the 3D-printed models were a useful tool for injection training.
Conclusions
Results suggest that 3D-printed models provided realistic training experience for injection procedures and seemed to allow participants to quickly master new injection techniques. These models offer a visual representation of human anatomy and could be a cost-saving alternative to commercial trainers.
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Risler Z, Magee MA, Mazza JM, Goodsell K, Au AK, Lewiss RE, Pugliese RS, Ku B. A Three-dimensional Printed Low-cost Anterior Shoulder Dislocation Model for Ultrasound-guided Injection Training. Cureus 2018; 10:e3536. [PMID: 30648069 PMCID: PMC6318112 DOI: 10.7759/cureus.3536] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Anterior shoulder dislocations are the most common, large joint dislocations that present to the emergency department (ED). Numerous studies support the use of intraarticular local anesthetic injections for the safe, effective, and time-saving reduction of these dislocations. Simulation training is an alternative and effective method for training compared to bedside learning. There are no commercially available ultrasound-compatible shoulder dislocation models. We utilized a three-dimensional (3D) printer to print a model that allows the visualization of the ultrasound anatomy (sonoanatomy) of an anterior shoulder dislocation. We utilized an open-source file of a shoulder, available from embodi3D® (Bellevue, WA, US). After approximating the relative orientation of the humerus to the glenoid fossa in an anterior dislocation, the humerus and scapula model was printed with an Ultimaker-2 Extended+ 3D® (Ultimaker, Cambridge, MA, US) printer using polylactic acid filaments. A 3D model of the external shoulder anatomy of a live human model was then created using Structure Sensor®(Occipital, San Francisco, CA, US), a 3D scanner. We aligned the printed dislocation model of the humerus and scapula within the resultant external shoulder mold. A pourable ballistics gel solution was used to create the final shoulder phantom. The use of simulation in medicine is widespread and growing, given the restrictions on work hours and a renewed focus on patient safety. The adage of "see one, do one, teach one" is being replaced by deliberate practice. Simulation allows such training to occur in a safe teaching environment. The ballistic gel and polylactic acid structure effectively reproduced the sonoanatomy of an anterior shoulder dislocation. The 3D printed model was effective for practicing an in-plane ultrasound-guided intraarticular joint injection. 3D printing is effective in producing a low-cost, ultrasound-capable model simulating an anterior shoulder dislocation. Future research will determine whether provider confidence and the use of intraarticular anesthesia for the management of shoulder dislocations will improve after utilizing this model.
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Affiliation(s)
- Zachary Risler
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | - Mark A Magee
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | - Jacob M Mazza
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | - Kelly Goodsell
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | - Arthur K Au
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | - Resa E Lewiss
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
| | | | - Bon Ku
- Emergency Medicine, Thomas Jefferson University, Philadelphia, USA
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15
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Li P, Yang Z, Jiang S. Tissue mimicking materials in image-guided needle-based interventions: A review. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 93:1116-1131. [PMID: 30274042 DOI: 10.1016/j.msec.2018.09.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 08/25/2018] [Accepted: 09/07/2018] [Indexed: 12/17/2022]
Abstract
Image-guided interventions are widely employed in clinical medicine, which brings significant revolution in healthcare in recent years. However, it is impossible for medical trainees to experience the image-guided interventions physically in patients due to the lack of certificated skills. Therefore, training phantoms, which are normally tissue mimicking materials, are widely used in medical research, training, and quality assurance. This review focuses on the tissue mimicking materials used in image-guided needle-based interventions. In this case, we need to investigate the microstructure characteristics and mechanical properties (for needle intervention), optical properties and acoustical properties (for imaging) of these training phantoms to compare with the related properties of human real tissues. The widely used base materials, additives and the corresponding concentrations of the training phantoms are summarized from the literatures in recent ten years. The microstructure characteristics, mechanical behavior, optical properties and acoustical properties of the tissue mimicking materials are investigated, accompanied with the common experimental methods, apparatus and theoretical algorithm. The influence of the concentrations of the base materials and additives on these characteristics are compared and classified. In this review, we assess a comprehensive overview of the existing techniques with the main accomplishments, and limitations as well as recommendations for tissue mimicking materials used in image-guided needle-based interventions.
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Affiliation(s)
- Pan Li
- Centre for Advanced Mechanisms and Robotics, School of Mechanical Engineering, Tianjin University, No. 135, Yaguan Road, Jinnan District, Tianjin City 300354, China
| | - Zhiyong Yang
- Centre for Advanced Mechanisms and Robotics, School of Mechanical Engineering, Tianjin University, No. 135, Yaguan Road, Jinnan District, Tianjin City 300354, China
| | - Shan Jiang
- Centre for Advanced Mechanisms and Robotics, School of Mechanical Engineering, Tianjin University, No. 135, Yaguan Road, Jinnan District, Tianjin City 300354, China.
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16
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Nayak R, Schifitto G, Doyley MM. Visualizing Angle-Independent Principal Strains in the Longitudinal View of the Carotid Artery: Phantom and In Vivo Evaluation. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:1379-1391. [PMID: 29685590 PMCID: PMC5960628 DOI: 10.1016/j.ultrasmedbio.2018.03.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 02/08/2018] [Accepted: 03/16/2018] [Indexed: 05/03/2023]
Abstract
Non-invasive vascular elastography can evaluate the stiffness of the carotid artery by visualizing the vascular strain distribution. Axial strain estimates of the longitudinal cross section of the carotid artery are sensitive to the angle between the artery and the transducer. Anatomical variations in branching and arching of the carotid artery can affect the assessment of arterial stiffness. In this study, we hypothesized that principal strain elastograms computed using compounded plane wave imaging can reliably visualize the strain distribution in the carotid artery, independent of the transducer angle. We corroborated this hypothesis by conducting phantom and in vivo studies using a commercial ultrasound scanner (Sonix RP, Ultrasonix Medical Corp., Richmond, BC, Canada). The phantom studies were conducted using a homogeneous cryogel vessel phantom. The goal of the phantom study was to assess the feasibility of visualizing the radial deformation in the longitudinal plane of the vessel phantom, independent of the transducer angle (±30°, ±20°, ±10° and 0°). The in vivo studies were conducted on 20 healthy human volunteers in the age group 50-60 y. All echo imaging was performed at a transmit frequency of 5 MHz and sampling frequency of 40 MHz. The elastograms obtained from the phantom study revealed that for straight vessels, which had their lumen parallel to the transducer, principal strains were similar to axial strains. At non-parallel configurations (angles ±30°, ±20° and ±10°), the magnitudes of the mean principal strains were within 2.5% of the parallel configuration (0° angle) estimates and, thus, were observed to be relatively unaffected by change in angle. However, in comparison, the magnitude of the axial strain decreased with increase in angle because of coordinate dependency. Further, the pilot in vivo study indicated that the principal and axial strain elastograms were similar for subjects with relatively straight arteries. However, for arteries with arched geometry, axial strains were significantly lower (p <0.01) than the corresponding principal vascular strains, which was consistent with the results obtained from the phantom study. In conclusion, the results of the phantom and in vivo studies revealed that principal strain elastograms computed using CPW imaging could reliably visualize angle-independent vascular strains in the longitudinal plane of the carotid artery.
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Affiliation(s)
- Rohit Nayak
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
| | - Giovanni Schifitto
- Department of Neurology, School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York, USA
| | - Marvin M Doyley
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA; Department of Biomedical Engineering, University of Rochester, Rochester, New York, USA
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Filippou V, Tsoumpas C. Recent advances on the development of phantoms using 3D printing for imaging with CT, MRI, PET, SPECT, and ultrasound. Med Phys 2018; 45. [PMID: 29933508 PMCID: PMC6849595 DOI: 10.1002/mp.13058] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 06/03/2018] [Accepted: 06/15/2018] [Indexed: 12/27/2022] Open
Abstract
PURPOSE Printing technology, capable of producing three-dimensional (3D) objects, has evolved in recent years and provides potential for developing reproducible and sophisticated physical phantoms. 3D printing technology can help rapidly develop relatively low cost phantoms with appropriate complexities, which are useful in imaging or dosimetry measurements. The need for more realistic phantoms is emerging since imaging systems are now capable of acquiring multimodal and multiparametric data. This review addresses three main questions about the 3D printers currently in use, and their produced materials. The first question investigates whether the resolution of 3D printers is sufficient for existing imaging technologies. The second question explores if the materials of 3D-printed phantoms can produce realistic images representing various tissues and organs as taken by different imaging modalities such as computer tomography (CT), positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), ultrasound (US), and mammography. The emergence of multimodal imaging increases the need for phantoms that can be scanned using different imaging modalities. The third question probes the feasibility and easiness of "printing" radioactive or nonradioactive solutions during the printing process. METHODS A systematic review of medical imaging studies published after January 2013 is performed using strict inclusion criteria. The databases used were Scopus and Web of Knowledge with specific search terms. In total, 139 papers were identified; however, only 50 were classified as relevant for this paper. In this review, following an appropriate introduction and literature research strategy, all 50 articles are presented in detail. A summary of tables and example figures of the most recent advances in 3D printing for the purposes of phantoms across different imaging modalities are provided. RESULTS All 50 studies printed and scanned phantoms in either CT, PET, SPECT, mammography, MRI, and US-or a combination of those modalities. According to the literature, different parameters were evaluated depending on the imaging modality used. Almost all papers evaluated more than two parameters, with the most common being Hounsfield units, density, attenuation and speed of sound. CONCLUSIONS The development of this field is rapidly evolving and becoming more refined. There is potential to reach the ultimate goal of using 3D phantoms to get feedback on imaging scanners and reconstruction algorithms more regularly. Although the development of imaging phantoms is evident, there are still some limitations to address: One of which is printing accuracy, due to the printer properties. Another limitation is the materials available to print: There are not enough materials to mimic all the tissue properties. For example, one material can mimic one property-such as the density of real tissue-but not any other property, like speed of sound or attenuation.
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Affiliation(s)
- Valeria Filippou
- Institute of Medical and Biological EngineeringFaculty of Mechanical EngineeringUniversity of LeedsLeedsLS2 9JTWest YorkshireUK
| | - Charalampos Tsoumpas
- Department of Biomedical Imaging ScienceSchool of MedicineUniversity of LeedsLeedsLS2 9NLWest YorkshireUK
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18
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Chee AJY, Yiu BYS, Ho CK, Yu ACH. Arterial Phantoms with Regional Variations in Wall Stiffness and Thickness. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:872-883. [PMID: 29361372 DOI: 10.1016/j.ultrasmedbio.2017.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 11/28/2017] [Accepted: 12/12/2017] [Indexed: 06/07/2023]
Abstract
Regional wall stiffening and thickening are two common pathological features of arteries. To account for these two features, we developed a new arterial phantom design framework to facilitate the development of vessel models that contain a lesion segment whose wall stiffness and thickness differ from those of other segments. This new framework is based on multi-part injection molding principles that sequentially casted the lesion segment and the flank segments of the vessel model using molding parts devised with computer-aided design tools. The vessel-mimicking material is created from polyvinyl alcohol cryogel, and its acoustic properties are similar to those of arteries. As a case demonstration, we fabricated a stenosed three-segment phantom composed of a central lesion segment (5.1-mm diameter, 1.95-mm wall thickness, 212.6-kPa elastic modulus) and two flank segments (6.0-mm diameter, 1.5-mm wall thickness, 133.7-kPa elastic modulus). B-mode imaging confirmed the difference in thickness between the lesion segment and flank segments of the phantom. Also, Doppler-based vessel wall displacement analysis revealed that when pulsatile flow was fed through the phantom (carotid pulse; 27 mL/s peak flow rate), the lesion segment distended less compared with the flank segments. Specifically, the three-beat averaged peak wall displacement in the lesion segment was measured as 0.28 mm, and it was significantly smaller than that of the flank segments (0.60 mm). It is anticipated that this new multi-segment arterial phantom can serve as a performance testbed for the evaluation of local arterial stiffness estimation algorithms.
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Affiliation(s)
- Adrian J Y Chee
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Billy Y S Yiu
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Chung Kit Ho
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Alfred C H Yu
- Schlegel Research Institute for Aging and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada.
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Maneas E, Xia W, Ogunlade O, Fonseca M, Nikitichev DI, David AL, West SJ, Ourselin S, Hebden JC, Vercauteren T, Desjardins AE. Gel wax-based tissue-mimicking phantoms for multispectral photoacoustic imaging. BIOMEDICAL OPTICS EXPRESS 2018; 9. [PMID: 29541509 PMCID: PMC5846519 DOI: 10.1364/boe.9.001151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Tissue-mimicking phantoms are widely used for the calibration, evaluation and standardisation of medical imaging systems, and for clinical training. For photoacoustic imaging, tissue-mimicking materials (TMMs) that have tuneable optical and acoustic properties, high stability, and mechanical robustness are highly desired. In this study, gel wax is introduced as a TMM that satisfies these criteria for developing photoacoustic imaging phantoms. The reduced scattering and optical absorption coefficients were independently tuned with the addition of TiO2 and oil-based inks. The frequency-dependent acoustic attenuation obeyed a power law; for native gel wax, it varied from 0.71 dB/cm at 3 MHz to 9.93 dB/cm at 12 MHz. The chosen oil-based inks, which have different optical absorption spectra in the range of 400 to 900 nm, were found to have good photostability under pulsed illumination with photoacoustic excitation light. Optically heterogeneous phantoms that comprised of inclusions with different concentrations of carbon black and coloured inks were fabricated, and multispectral photoacoustic imaging was performed with an optical parametric oscillator and a planar Fabry-Pérot sensor. We conclude that gel wax is well suited as a TMM for multispectral photoacoustic imaging.
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Affiliation(s)
- Efthymios Maneas
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Wenfeng Xia
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Olumide Ogunlade
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Martina Fonseca
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Daniil I. Nikitichev
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Anna L. David
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Institute for Women’s Health, University College London, 86-96 Chenies Mews, London WC1E 6HX,
UK
- Department of Development and Regeneration, KU Leuven (Katholieke Universiteit),
Belgium
| | - Simeon J. West
- Department of Anaesthesia, University College Hospital, Main Theatres, Maple Bridge Link Corridor, Podium 3, 235 Euston Road, London NW1 2BU,
UK
| | - Sebastien Ourselin
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Jeremy C. Hebden
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Tom Vercauteren
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
| | - Adrien E. Desjardins
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ,
UK
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT,
UK
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Du YC, Shih JB, Wu MJ, Chiou CY. Development of an AVF Stenosis Assessment Tool for Hemodialysis Patients Using Robotic Ultrasound System. MICROMACHINES 2018; 9:E51. [PMID: 30393327 PMCID: PMC6187484 DOI: 10.3390/mi9020051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/24/2018] [Accepted: 01/25/2018] [Indexed: 11/17/2022]
Abstract
With the aging population and lifestyle changes, the number of hemodialysis (HD) patients increases year by year. The arteriovenous fistula (AVF) is the gold standard vascular access used to access the blood for HD treatment. Since the status of stenosis affects HD efficiency, current clinical practices usually use a Doppler ultrasound imaging system to assess the parameters of the stenosis, such as the degree of stenosis (DOS). Unfortunately, this is a very time-consuming task. Furthermore, it is difficult to stably maintain the ultrasound probe for a prolonged period to give doctors clearer or reproducible images. In this study, a robotic ultrasound system (RUS) with ultrasound sequential imaging analysis was designed to evaluate the DOS of the AVF. The sequential imaging analysis was capable of image smoothing and vessel boundary detection. It enabled clinicians to mark the thickness of the plaque for further processing. Finally, the system was used to reconstruct 3D models of fistulas and calculated the DOS for clinical assessment. We also designed a pressure sensing module attached to the ultrasound probe to prevent the probe from coming loose, vibrating, and exerting abnormal pressure on the skin. In the phantom test, the results showed that the error of the DOS that was calculated by RUS was less than 3%. The results of clinical trials obtained from ten patients show that the error between the RUS and clinicians' measurement was about 10% and had a highly linear correlation (R Square > 0.95). In addition, the reproducibility error was about 3% and could effectively save about 46% of the time during clinical examinations.
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Affiliation(s)
- Yi-Chun Du
- Department of Electrical Engineering, Southern Taiwan University of Science and Technology, No. 1, Nan-Tai Street, Yungkang Dist., Tainan 71005, Taiwan.
| | - Jheng-Bang Shih
- Department of Electrical Engineering, Southern Taiwan University of Science and Technology, No. 1, Nan-Tai Street, Yungkang Dist., Tainan 71005, Taiwan.
| | - Ming-Jui Wu
- Department of Electrical Engineering, Southern Taiwan University of Science and Technology, No. 1, Nan-Tai Street, Yungkang Dist., Tainan 71005, Taiwan.
- Department of Internal Medicine, Kaohsiung Veterans General Hospital Tainan Branch, Tainan 71051, Taiwan.
| | - Chung-Yi Chiou
- Department of Electrical Engineering, Southern Taiwan University of Science and Technology, No. 1, Nan-Tai Street, Yungkang Dist., Tainan 71005, Taiwan.
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Maneas E, Xia W, Nikitichev DI, Daher B, Manimaran M, Wong RYJ, Chang CW, Rahmani B, Capelli C, Schievano S, Burriesci G, Ourselin S, David AL, Finlay MC, West SJ, Vercauteren T, Desjardins AE. Anatomically realistic ultrasound phantoms using gel wax with 3D printed moulds. Phys Med Biol 2018; 63:015033. [PMID: 29186007 PMCID: PMC5802334 DOI: 10.1088/1361-6560/aa9e2c] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Here we describe methods for creating tissue-mimicking ultrasound phantoms based on patient anatomy using a soft material called gel wax. To recreate acoustically realistic tissue properties, two additives to gel wax were considered: paraffin wax to increase acoustic attenuation, and solid glass spheres to increase backscattering. The frequency dependence of ultrasound attenuation was well described with a power law over the measured range of 3–10 MHz. With the addition of paraffin wax in concentrations of 0 to 8 w/w%, attenuation varied from 0.72 to 2.91 dB cm−1 at 3 MHz and from 6.84 to 26.63 dB cm−1 at 10 MHz. With solid glass sphere concentrations in the range of 0.025–0.9 w/w%, acoustic backscattering consistent with a wide range of ultrasonic appearances was achieved. Native gel wax maintained its integrity during compressive deformations up to 60%; its Young’s modulus was 17.4 ± 1.4 kPa. The gel wax with additives was shaped by melting and pouring it into 3D printed moulds. Three different phantoms were constructed: a nerve and vessel phantom for peripheral nerve blocks, a heart atrium phantom, and a placental phantom for minimally-invasive fetal interventions. In the first, nerves and vessels were represented as hyperechoic and hypoechoic tubular structures, respectively, in a homogeneous background. The second phantom comprised atria derived from an MRI scan of a patient with an intervening septum and adjoining vena cavae. The third comprised the chorionic surface of a placenta with superficial fetal vessels derived from an image of a post-partum human placenta. Gel wax is a material with widely tuneable ultrasound properties and mechanical characteristics that are well suited for creating patient-specific ultrasound phantoms in several clinical disciplines.
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Affiliation(s)
- Efthymios Maneas
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom. Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ, United Kingdom. These authors contributed equally to this work
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Bücking TM, Hill ER, Robertson JL, Maneas E, Plumb AA, Nikitichev DI. From medical imaging data to 3D printed anatomical models. PLoS One 2017; 12:e0178540. [PMID: 28562693 PMCID: PMC5451060 DOI: 10.1371/journal.pone.0178540] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 05/15/2017] [Indexed: 12/17/2022] Open
Abstract
Anatomical models are important training and teaching tools in the clinical environment and are routinely used in medical imaging research. Advances in segmentation algorithms and increased availability of three-dimensional (3D) printers have made it possible to create cost-efficient patient-specific models without expert knowledge. We introduce a general workflow that can be used to convert volumetric medical imaging data (as generated by Computer Tomography (CT)) to 3D printed physical models. This process is broken up into three steps: image segmentation, mesh refinement and 3D printing. To lower the barrier to entry and provide the best options when aiming to 3D print an anatomical model from medical images, we provide an overview of relevant free and open-source image segmentation tools as well as 3D printing technologies. We demonstrate the utility of this streamlined workflow by creating models of ribs, liver, and lung using a Fused Deposition Modelling 3D printer.
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Affiliation(s)
- Thore M. Bücking
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
- * E-mail:
| | - Emma R. Hill
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - James L. Robertson
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Efthymios Maneas
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Andrew A. Plumb
- Centre for Medical Imaging, University College London, London, United Kingdom
| | - Daniil I. Nikitichev
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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Zhou X, Kenwright DA, Wang S, Hossack JA, Hoskins PR. Fabrication of Two Flow Phantoms for Doppler Ultrasound Imaging. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2017; 64:53-65. [PMID: 27925588 DOI: 10.1109/tuffc.2016.2634919] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Flow phantoms are widely used in studies associated with Doppler ultrasound measurements, acting as an effective experimental validation system in cardiovascular-related research and in new algorithm/instrumentation development. The development of materials that match the acoustic and mechanical properties of the vascular system is of great interest while designing flow phantoms. Although recipes that meet the flow phantom standard defined by the International Electrotechnical Commission 61685 are already available in the literature, the standard procedure for material preparations and phantom fabrications has not been well established. In this paper, two types of flow phantoms, with and without blood vessel mimic, are described in detail in terms of the material preparation and phantom fabrication. The phantom materials chosen for the two phantoms are from published phantom studies, and their physical properties have been investigated previously. Both the flow phantoms have been scanned by ultrasound scanners and images from different modes are presented. These phantoms may be used in the validation and characterization of Doppler ultrasound measurements in blood vessels with a diameter above 1 mm.
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