Teaching image-guided stereotactic methodology and functional neuroanatomy of the thalamus and pallidum: A simple ex vivo technique

Abstract Cochlear implants include an electrode array (EA) which needs to be inserted into the cochlea. Insertion tests using artificial cochlear models (ACM) or ex vivo specimens are widely used methods during EA development to characterize EA design properties, including insertion forces. Measured forces are directly linked to the orientation of the cochlear lumen with respect to the insertion axis of the test bench. While desired insertion directions in ACM experiments can be predefined by design, specimens are individually shaped and the cochlear lumen is embedded invisibly. Therefore, a new method for accurate, individual specimen positioning is required. A key element of the proposed method is a customizable pose setting adapter (PSA) used to adjust the specimen’s fine positioning. After rigid fixation of the specimen to a holder featuring spherical registration markers and subsequent cone beam computed tomography the desired insertion direction is planned. The planned data is used to calculate the individual shape of the PSA. Finally, the PSA is 3D printed and mounted between force sensor and specimen holder to correctly align the specimen to the test bench’s insertion axis. All necessary hard- and software have been developed including the specimen holder, a software for registration and trajectory planning, and a custom Matlab script whose output drives a parametric CAD file of the PSA. Positioning accuracy was determined in a first trial using 10 virtual trajectories and was found to be 0.23 ± 0.12 mm and 0.38 ± 0.17°. The presented stereotactic positioning procedure enables high repeatability in future ex vivo insertion experiments due to accurate, image-guided control of the insertion direction.

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Image-guided sonoporation in an ex vivo machine perfused porcine liver

Journal of Therapeutic Ultrasound ◽

10.1186/2050-5736-3-s1-p99 ◽

2015 ◽

Vol 3 (S1) ◽

Author(s):

Christina Keravnou ◽

Christophoros Mannaris ◽

Maria-Louisa Izamis ◽

Michalakis Averkiou

Keyword(s):

Ex Vivo ◽

Porcine Liver ◽

Image Guided

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Modeling of Radiofrequency Ablation Lesions for Image-Guided Arrhythmia Therapy: A Preliminary ex vivo Demonstration

Augmented Environments for Computer-Assisted Interventions - Lecture Notes in Computer Science ◽

10.1007/978-3-642-38085-3_4 ◽

2013 ◽

pp. 22-33 ◽

Cited By ~ 1

Author(s):

Cristian A. Linte ◽

Jon J. Camp ◽

David R. Holmes ◽

Maryam E. Rettmann ◽

Richard A. Robb

Keyword(s):

Radiofrequency Ablation ◽

Ex Vivo ◽

Image Guided ◽

Arrhythmia Therapy

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CT mapping of saline distribution after infusion of saline into the liver in an ex vivo animal model. How much tissue is actually infused in an image-guided procedure?

Physica Medica ◽

10.1016/j.ejmp.2012.03.001 ◽

2013 ◽

Vol 29 (2) ◽

pp. 188-195 ◽

Cited By ~ 4

Author(s):

Fernando Burdío ◽

Enrique Berjano ◽

Olga Millan ◽

Luis Grande ◽

Ignasi Poves ◽

...

Keyword(s):

Animal Model ◽

Ex Vivo ◽

Image Guided

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Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance

Sci ◽

10.3390/sci3010008 ◽

2021 ◽

Vol 3 (1) ◽

pp. 8

Author(s):

Naama Lev-Cohain ◽

Gal Sapir ◽

Sivaranjan Uppala ◽

Atara Nardi-Schreiber ◽

Shraga Goldberg ◽

...

Keyword(s):

Magnetic Resonance ◽

Ex Vivo ◽

Human Subjects ◽

Alanine Transaminase ◽

Small Hepatocellular Carcinoma ◽

Mri Scan ◽

Hyperpolarized 13C ◽

Image Guided ◽

Metabolic Monitoring

The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a noninvasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects.

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Image-guided ex-vivo targeting accuracy using a laparoscopic tissue localization system

10.1117/12.713884 ◽

2007 ◽

Author(s):

Jerry Bieszczad ◽

Eric Friets ◽

Darin Knaus ◽

Thomas Rauth ◽

Alan Herline ◽

...

Keyword(s):

Ex Vivo ◽

Tissue Localization ◽

Localization System ◽

Image Guided ◽

Targeting Accuracy

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Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance

Sci ◽

10.3390/sci2020043 ◽

2020 ◽

Vol 2 (2) ◽

pp. 43

Author(s):

Naama Lev-Cohain ◽

Gal Sapir ◽

Sivaranjan Uppala ◽

Atara Nardi-Schreiber ◽

Shraga Nahum Goldberg ◽

...

Keyword(s):

Magnetic Resonance ◽

Ex Vivo ◽

Human Subjects ◽

Small Hepatocellular Carcinoma ◽

Mri Scan ◽

Hyperpolarized 13C ◽

Non Invasive ◽

Image Guided ◽

Metabolic Monitoring

The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a non-invasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects.

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Identification of cholesteryl esters in human carotid atherosclerosis by ex vivo image-guided proton MRS

The Journal of Lipid Research ◽

10.1194/jlr.m500431-jlr200 ◽

2005 ◽

Vol 47 (2) ◽

pp. 310-317 ◽

Cited By ~ 23

Author(s):

Frederick L. Ruberg ◽

Jason Viereck ◽

Alkystis Phinikaridou ◽

Ye Qiao ◽

Joseph Loscalzo ◽

...

Keyword(s):

Carotid Atherosclerosis ◽

Ex Vivo ◽

Cholesteryl Esters ◽

Proton Mrs ◽

Image Guided ◽

Human Carotid

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CREATION OF CLINICALLY-DIFFERENTIAL TUMOR MIMIC MODEL USING VASELINE-BASED MATERIALS WITH BARIUM SULFATE FOR THE VALIDATION OF REAL-TIME ULTRASOUND IMAGE-GUIDED LIVER BIOPSY SYSTEM

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237216500034 ◽

2016 ◽

Vol 28 (01) ◽

pp. 1650003

Author(s):

Cheng Li ◽

Jin Yao Teo ◽

Jiaze Wu ◽

Apoorva Gogna ◽

Bien Soo Tan ◽

...

Keyword(s):

Liver Biopsy ◽

Real Time ◽

Barium Sulfate ◽

Ex Vivo ◽

Ultrasound Image ◽

Tumor Model ◽

Palpable Mass ◽

Image Guided ◽

In Vivo Experiments

Testing objects are important for the validation of developing biopsy systems. Unfortunately, they are very hard to obtain. Motivated by this issue, the purpose of this study is to develop a technique for the easy creation of a model to simulate tumors of different sizes inside porcine livers, which could be used for ultrasound image-guided liver biopsy amongst other applications, and evaluate its performance by comparing to the more widely-used approaches in-vivo and ex-vivo. In this study, a Vaseline-based tumor model, and a more widely-used agar-based tumor model to provide comparison with the proposed method were created and injected into porcine livers as biopsy targets. The clinician located simulated tumors using real-time 2D imaging under the guidance of a robotic arm to delivery the biopsy in ex-vivo and in-vivo experiments. The results show that the optimum tumor model was created from a mixture of Vaseline, glycerol, and barium sulfate which can be easily produced and injected. All Vaseline-based simulated tumors were of solid, palpable mass on gross examination, and ultrasound imaging revealed clearly visible lesions. The clinician successfully performed ultrasound image guided liver biopsy in all the trials (10/10) in the ex-vivo experiment, and 2 out of 3 trials (2/3) in the in-vivo experiment on this optimum tumor model. We described a novel technique of creating solid liver tumor models that can be used for ultrasound image-guided liver biopsy.

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