Planning Irreversible Electroporation in the Porcine Kidney: Are Numerical Simulations Reliable for Predicting Empiric Ablation Outcomes?

PurposeNumerical simulations are used for treatment planning in clinical applications of irreversible electroporation (IRE) to determine ablation size and shape. To assess the reliability of simulations for treatment planning, we compared simulation results with empiric outcomes of renal IRE using computed tomography (CT) and histology in an animal model.MethodsThe ablation size and shape for six different IRE parameter sets (70–90 pulses, 2,000–2,700 V, 70–100 µs) for monopolar and bipolar electrodes was simulated using a numerical model. Employing these treatment parameters, 35 CT-guided IRE ablations were created in both kidneys of six pigs and followed up with CT immediately and after 24 h. Histopathology was analyzed from postablation day 1.ResultsAblation zones on CT measured 81 ± 18 % (day 0, p ≤ 0.05) and 115 ± 18 % (day 1, p ≤ 0.09) of the simulated size for monopolar electrodes, and 190 ± 33 % (day 0, p ≤ 0.001) and 234 ± 12 % (day 1, p ≤ 0.0001) for bipolar electrodes. Histopathology indicated smaller ablation zones than simulated (71 ± 41 %, p ≤ 0.047) and measured on CT (47 ± 16 %, p ≤ 0.005) with complete ablation of kidney parenchyma within the central zone and incomplete ablation in the periphery.ConclusionBoth numerical simulations for planning renal IRE and CT measurements may overestimate the size of ablation compared to histology, and ablation effects may be incomplete in the periphery.

[1]  Rafael V. Davalos,et al.  Experimental Characterization and Numerical Modeling of Tissue Electrical Conductivity during Pulsed Electric Fields for Irreversible Electroporation Treatment Planning , 2012, IEEE Transactions on Biomedical Engineering.

[2]  Zhao Li,et al.  Immunologic Response to Tumor Ablation with Irreversible Electroporation , 2012, PloS one.

[3]  Boris Rubinsky,et al.  A statistical model for multidimensional irreversible electroporation cell death in tissue , 2010, Biomedical engineering online.

[4]  S. Silverman,et al.  Comparison of percutaneous and surgical approaches to renal tumor ablation: metaanalysis of effectiveness and complication rates. , 2008, Journal of vascular and interventional radiology : JVIR.

[5]  Majid Maybody,et al.  Renal tissue ablation with irreversible electroporation: preliminary results in a porcine model. , 2011, Urology.

[6]  J. Yi,et al.  Changes of apoptosis in tumor tissues with time after irreversible electroporation. , 2013, Biochemical and biophysical research communications.

[7]  Raphael C. Lee,et al.  Cell Injury by Electric Forces , 2005, Annals of the New York Academy of Sciences.

[8]  Samuel K. Park,et al.  Irreversible electroporation: evaluation of nonthermal and thermal ablative capabilities in the porcine kidney. , 2013, Urology.

[9]  Jacob Sosna,et al.  Irreversible Electroporation: Treatment Effect Is Susceptible to Local Environment and Tissue Properties , 2013 .

[10]  Boris Rubinsky,et al.  Electrical field and temperature model of nonthermal irreversible electroporation in heterogeneous tissues. , 2009, Journal of biomechanical engineering.

[11]  P. Shires,et al.  Real-time ultrasound imaging of irreversible electroporation in a porcine liver model adequately characterizes the zone of cellular necrosis. , 2012, HPB : the official journal of the International Hepato Pancreato Biliary Association.

[12]  Helen Kavnoudias,et al.  Investigation of the safety of irreversible electroporation in humans. , 2011, Journal of vascular and interventional radiology : JVIR.

[13]  B. Benway.  Irreversible Electroporation of Renal Cell Carcinoma: A First-in-Man Phase I Clinical Study: Pech M, Janitzky A, Wendler JJ, et al (Univ of Magdeburg, Germany) Cardiovasc Intervent Radiol 34:132-138, 2011§ , 2011 .

[14]  Markus Porsch,et al.  Urinary Tract Effects After Multifocal Nonthermal Irreversible Electroporation of the Kidney: Acute and Chronic Monitoring by Magnetic Resonance Imaging, Intravenous Urography and Urinary Cytology , 2012, CardioVascular and Interventional Radiology.

[15]  Markus Porsch,et al.  Angiography in the Isolated Perfused Kidney: Radiological Evaluation of Vascular Protection in Tissue Ablation by Nonthermal Irreversible Electroporation , 2012, CardioVascular and Interventional Radiology.

[16]  Jens Ricke,et al.  Irreversible Electroporation of Renal Cell Carcinoma: A First-in-Man Phase I Clinical Study , 2011, CardioVascular and Interventional Radiology.

[17]  Boris Rubinsky,et al.  Tumor Ablation with Irreversible Electroporation , 2007, PloS one.

[18]  S. Hayasaka,et al.  Oncologic efficacy of CT-guided percutaneous radiofrequency ablation of renal cell carcinomas. , 2007, AJR. American journal of roentgenology.

[19]  J. Raman,et al.  Management and prevention of renal ablative therapy complications , 2010, World Journal of Urology.

[20]  F. Keeley,et al.  Prevention and handling of complications of renal focal therapies. , 2010, Journal of endourology.

[21]  Yuman Fong,et al.  Ablation of perivascular hepatic malignant tumors with irreversible electroporation. , 2012, Journal of the American College of Surgeons.

[22]  D. Gervais,et al.  Radiofrequency ablation of renal cell carcinoma: part 2, Lessons learned with ablation of 100 tumors. , 2005, AJR. American journal of roentgenology.

[23]  C. Georgiades,et al.  Safety and efficacy of CT-guided percutaneous cryoablation for renal cell carcinoma. , 2008, Journal of vascular and interventional radiology : JVIR.

[24]  Boris Rubinsky,et al.  Irreversible Electroporation in Medicine , 2007, Technology in cancer research & treatment.

[25]  S. Goldberg,et al.  Irreversible electroporation ablation: is all the damage nonthermal? , 2013, Radiology.

[26]  B. Rubinsky,et al.  Tissue Ablation with Irreversible Electroporation , 2005, Annals of Biomedical Engineering.

[27]  T. Atwell,et al.  Percutaneous cryoablation of solitary sporadic renal cell carcinomas , 2012, BJU international.

[28]  D. Gervais,et al.  Radiofrequency ablation of renal cell carcinoma: part 1, Indications, results, and role in patient management over a 6-year period and ablation of 100 tumors. , 2005, AJR. American journal of roentgenology.

[29]  F. Fischbach,et al.  Short- and Mid-term Effects of Irreversible Electroporation on Normal Renal Tissue: An Animal Model , 2013, CardioVascular and Interventional Radiology.

[30]  Jon F Edd,et al.  Mathematical Modeling of Irreversible Electroporation for Treatment Planning , 2007, Technology in cancer research & treatment.