@article {227, title = {First-in-human demonstration of floating EMG sensors and stimulators wirelessly powered and operated by volume conduction}, journal = {Journal of NeuroEngineering and Rehabilitation}, volume = {21}, year = {2024}, pages = {4}, chapter = {4}, doi = {10.1186/s12984-023-01295-5}, url = {https://doi.org/10.1186/s12984-023-01295-5}, author = {Laura Becerra-Fajardo and Jesus Minguillon and Krob, Marc O. and Camila Rogrigues and Miguel Gonz{\'a}lez-S{\'a}nchez and {\'A}lvaro Meg{\'\i}a-Garc{\'\i}a and Redondo Gal{\'a}n, Carolina and Guiti{\'e}rrez Henares, Francisco and Albert Comerma and del Ama, Antonio J. and {\'A}ngel Gil-Agudo and Francisco Grandas and Andreas Schneider and Filipe O. Barroso and Antoni Ivorra} } @article {226, title = {Dynamics of High-Density Unipolar Epicardial Electrograms During PFA}, journal = {Circulation: Arrhythmia and Electrophysiology}, year = {2023}, pages = {e011914}, chapter = {e011914}, doi = {10.1161/CIRCEP.123.011914}, url = {https://www.ahajournals.org/doi/10.1161/CIRCEP.123.011914}, author = {Gerard Amor{\'o}s-Figueras and Sergi Casabella-Ramon and Zoraida Moreno-Weidmann and Antoni Ivorra and Jose M. Guerra and Tomas Garcia-Sanchez} } @article {228, title = {Effects of Contact Force on Lesion Size During Pulsed Field Catheter Ablation: Histochemical Characterization of Ventricular Lesion Boundaries}, journal = {Circulation: Arrhythmia and Electrophysiology}, volume = {(Online ahead of print.)}, year = {2023}, pages = {e012026}, doi = {10.1161/CIRCEP.123.012026}, url = {https://doi.org/10.1161/CIRCEP.123.012026}, author = {Hiroshi Nakagawa and Q. Castellv{\'\i} and Robert Neal and Steven Girouard and Jacob Laughner and Atsushi Ikeda and Masafumi Sugawara and Yoshimori An and Hussein, Ayman A. and Shady Nakhla and Tyler Taigen and Jakub Srounbek and Mohamed Kanj and Pasquale Santangeli and Walid I. Saliba and Antoni Ivorra and Oussama M. Wazni} } @article {215, title = {Powering Electronic Implants by High Frequency Volume Conduction: In Human Validation}, journal = {IEEE Transactions on Biomedical Engineering}, volume = {70}, year = {2023}, month = {08/2022}, pages = {659-670}, chapter = {659}, doi = {10.1109/TBME.2022.3200409}, url = {https://ieeexplore.ieee.org/document/9864046}, author = {Jesus Minguillon and Marc Tudela-Pi and Laura Becerra-Fajardo and Enric Perera-Bel and del Ama, Antonio J. and {\'A}ngel Gil-Agudo and {\'A}lvaro Meg{\'\i}a-Garc{\'\i}a and Aracelys Garc{\'\i}a-Moreno and Antoni Ivorra} } @article {213, title = {Auricular transcutaneous vagus nerve stimulation acutely modulates brain connectivity in mice}, journal = {Frontiers in Cellular Neuroscience}, volume = {16}, year = {2022}, pages = {856855}, chapter = {856855}, doi = {10.3389/fncel.2022.856855}, url = {https://www.frontiersin.org/articles/10.3389/fncel.2022.856855/abstract}, author = {Cecilia Brambilla-Pisoni and Emma Mu{\~n}oz-Moreno and Ianire Gallego-Amaro and Rafael Maldonado and Antoni Ivorra and Guadalupe Soria and Andr{\'e}s Ozaita} } @article {217, title = {A computational comparison of Radiofrequency and Pulsed Field Ablation in terms of lesion morphology in the cardiac chamber}, journal = {Scientific Reports}, volume = {12}, year = {2022}, chapter = {16144}, doi = {10.1038/s41598-022-20212-9}, url = {https://doi.org/10.1038/s41598-022-20212-9}, author = {Mario G{\'o}mez-Barea and Tomas Garcia-Sanchez and Antoni Ivorra} } @article {214, title = {Floating EMG Sensors and Stimulators Wirelessly Powered and Operated by Volume Conduction for Networked Neuroprosthetics}, journal = {Journal of NeuroEngineering and Rehabilitation}, volume = {19}, year = {2022}, pages = {57}, chapter = {57}, doi = {10.1186/s12984-022-01033-3}, url = {https://doi.org/10.1186/s12984-022-01033-3}, author = {Laura Becerra-Fajardo and Krob, Marc O. and Jesus Minguillon and Camila Rogrigues and Christine Welsch and Marc Tudela-Pi and Albert Comerma and Filipe O. Barroso and Andreas Schneider and Antoni Ivorra} } @article {223, title = {Implantable Sensor for Measuring and Monitoring Intravascular Pressure, System Comprising Said Sensor and Method for Operating Thereof}, year = {2022}, edition = {A61B5/0215; A61B5/07; A61F2/90}, chapter = {WO 2022/184801 A1}, author = {Antoni Ivorra and Laura Becerra-Fajardo and Albert Comerma and Jesus Minguillon} } @article {209, title = {Modeling methods for treatment planning in overlapping electroporation treatments}, journal = {IEEE Transactions on Biomedical Engineering}, volume = {69}, year = {2022}, month = {09/2021}, pages = {1318 - 1327}, chapter = {1318}, doi = {10.1109/TBME.2021.3115029}, url = {https://ieeexplore.ieee.org/document/9547807}, author = {Enric Perera-Bel and Borja Mercadal and Tomas Garcia-Sanchez and Miguel A. Gonz{\'a}lez-Ballester and Antoni Ivorra} } @article {218, title = {Parametric study of Pulsed Field Ablation with biphasic waveforms in an in vivo heart model: the role of frequency}, journal = {Circulation: Arrhythmia and Electrophysiology}, volume = {15}, year = {2022}, pages = {693-705}, chapter = {693}, doi = {10.1161/CIRCEP.122.010992}, url = {https://www.ahajournals.org/doi/abs/10.1161/CIRCEP.122.010992}, author = {Tomas Garcia-Sanchez and Gerard Amor{\'o}s-Figueras and Esther Jorge and Mar{\'\i}a C. Campos and Elad Maor and Jose M. Guerra and Antoni Ivorra} } @article {224, title = {PIRET {\textemdash} A Platform for Treatment Planning in Electroporation-Based Therapies}, journal = {Transactions on Biomedical Engineering}, volume = {(Accepted)}, year = {2022}, author = {Enric Perera-Bel and Kenneth N. Aycock and Zaid Salameh and Mario G{\'o}mez-Barea and Rafael Davalos and Antoni Ivorra and Miguel A. Gonz{\'a}lez-Ballester} } @article {216, title = {Wireless networks of injectable microelectronic stimulators based on rectification of volume conducted high frequency currents}, journal = {Journal of Neural Engineering}, volume = {19}, year = {2022}, pages = {056015}, chapter = {056015}, doi = {10.1088/1741-2552/ac8dc4}, url = {https://iopscience.iop.org/article/10.1088/1741-2552/ac8dc4}, author = {Aracelys Garc{\'\i}a-Moreno and Albert Comerma and Marc Tudela-Pi and Jesus Minguillon and Laura Becerra-Fajardo and Antoni Ivorra} } @article {206, title = {Comparing High-Frequency With Monophasic Electroporation Protocols in an In Vivo Beating Heart Model}, journal = {JACC: Clinical Electrophysiology}, volume = {7}, year = {2021}, pages = {959-964}, chapter = {959}, doi = {10.1016/j.jacep.2021.05.003}, author = {Eyal Heller and Tomas Garcia-Sanchez and Yonatan Moshkovits and Raul Rabinovici and Dvora Grynberg and Amit Segev and Samuel Asirvatham and Antoni Ivorra and Elad Maor} } @article {221, title = {Implantable Electronic Sensing System for Measuring and Monitoring Medical Parameters}, year = {2021}, edition = {A61B5/00; A61B5/145; A61B5/1455; A61B5/1486}, chapter = {WO 2021/043481 A1}, author = {Antoni Ivorra and Q. Castellv{\'\i} and Laura Becerra-Fajardo} } @conference {211, title = {Injectable Temperature Sensors Based on Passive Rectification of Volume-Conducted Currents}, booktitle = {2021 IEEE Biomedical Circuits and Systems Conference (BioCAS)}, year = {2021}, publisher = {IEEE}, organization = {IEEE}, address = {Berlin, Germany}, doi = {10.1109/BioCAS49922.2021.9645006}, author = {Laura Becerra-Fajardo and Aracelys Garc{\'\i}a-Moreno and Alvarez-De-Eulate, Nerea and Antoni Ivorra} } @article {207, title = {Volume Conduction for Powering Deeply Implanted Networks of Wireless Injectable Medical Devices: a Numerical Parametric Analysis}, journal = {IEEE Access }, volume = {9}, year = {2021}, pages = {100594-100605}, chapter = {100594-100605}, doi = {10.1109/ACCESS.2021.3096729}, url = {https://ieeexplore.ieee.org/document/9481290}, author = {Marc Tudela-Pi and Jesus Minguillon and Laura Becerra-Fajardo and Antoni Ivorra} } @article {184, title = {Auricular transcutaneous vagus nerve stimulation improves memory persistence in na{\"\i}ve mice and in an intellectual disability mouse model}, journal = {Brain Stimulation}, volume = {13}, year = {2020}, pages = {494-498}, chapter = {494}, doi = {10.1016/j.brs.2019.12.024}, url = {https://doi.org/10.1016/j.brs.2019.12.024}, author = {Anna V{\'a}zquez-Oliver and Cecilia Brambilla-Pisoni and Mikel Domingo-Gainza and Rafael Maldonado and Antoni Ivorra and Andr{\'e}s Ozaita} } @article {187, title = {Dynamics of Cell Death After Conventional IRE and H-FIRE Treatments}, journal = {Annals of Biomedical Engineering}, volume = {48}, year = {2020}, pages = {1451{\textendash}1462}, chapter = {pages1451}, doi = {10.1007/s10439-020-02462-8}, url = {https://doi.org/10.1007/s10439-020-02462-8}, author = {Borja Mercadal and Natalie Beitel-White and Kenneth N. Aycock and Q. Castellv{\'\i} and Rafael Davalos and Antoni Ivorra} } @article {199, title = {Electrophoresis-assisted accumulation of conductive nanoparticles for the enhancement of cell electropermeabilization}, journal = {Bioelectrochemistry}, volume = {(In Press, Journal Pre-proof)}, year = {2020}, pages = {107642}, chapter = {107642}, doi = {10.1016/j.bioelechem.2020.107642}, url = {https://doi.org/10.1016/j.bioelechem.2020.107642}, author = {Amina Ghorbel and Franck M. Andr{\'e} and Lluis M. Mir and Tomas Garcia-Sanchez} } @article {198, title = {EView: An electric field visualization web platform for electroporation-based therapies}, journal = {Computer Methods and Programs in Biomedicine}, volume = {197}, year = {2020}, pages = {105682}, chapter = {105682}, doi = {10.1016/j.cmpb.2020.105682}, author = {Enric Perera-Bel and Carlos Yag{\"u}e and Borja Mercadal and Mario Ceresa and Natalie Beitel-White and Rafael Davalos and Miguel A. Gonz{\'a}lez-Ballester and Antoni Ivorra} } @article {192, title = {GaN-Based Versatile Waveform Generator for Biomedical Applications of Electroporation}, journal = {IEEE Access}, volume = {(Early Access)}, year = {2020}, doi = {10.1109/ACCESS.2020.2996426}, author = {H{\'e}ctor Sarnago and Jos{\'e} M. Burd{\'\i}o and Tomas Garcia-Sanchez and Lluis M. Mir and Ignacio {\'A}lvarez-Gariburo and {\'O}scar Luc{\'\i}a} } @article {185, title = {High-voltage pulsed electric field laboratory device with asymmetric voltage multiplier for marine macroalgae electroporation}, journal = {Innovative Food Science and Emerging Technologies}, volume = {(In press, Journal Pre-proof)}, year = {2020}, doi = {10.1016/j.ifset.2020.102288}, author = {Klimentiy Levkov and Yoav Linzon and Borja Mercadal and Antoni Ivorra and C{\'e}sar Gonz{\'a}lez and Alexander Golberg} } @conference {210, title = {In Vitro Evaluation of a Protocol and an Architecture for Bidirectional Communications in Networks of Wireless Implants Powered by Volume Conduction}, booktitle = {5th International Conference on Neurorehabilitation (ICNR2020)}, volume = {28}, year = {2020}, pages = {103-108}, publisher = {Springer Nature}, organization = {Springer Nature}, edition = {Converging Clinical and Engineering Research on Neurorehabilitation IV, Biosystems \& Biorobotics}, doi = {10.1007/978-3-030-70316-5_17}, author = {Laura Becerra-Fajardo and Jesus Minguillon and Camila Rogrigues and Filipe O. Barroso and Pons, Jos{\'e} Luis and Antoni Ivorra} } @article {188, title = {In vitro study on the mechanisms of action of electrolytic electroporation (E2)}, journal = {Bioelectrochemistry}, volume = {133}, year = {2020}, pages = {107482}, chapter = {107482}, doi = {10.1016/j.bioelechem.2020.107482}, url = {https://doi.org/10.1016/j.bioelechem.2020.107482}, author = {Nina Klein and Borja Mercadal and Michael Stehling and Antoni Ivorra} } @article {193, title = {Injectable Sensors Based on Passive Rectification of Volume-Conducted Currents}, journal = {IEEE Transactions on Biomedical Circuits and Systems}, volume = {14}, year = {2020}, pages = {867-878}, chapter = {867}, doi = {10.1109/TBCAS.2020.3002326}, url = {https://ieeexplore.ieee.org/document/9117042}, author = {Shahid Malik and Q. Castellv{\'\i} and Laura Becerra-Fajardo and Marc Tudela-Pi and Aracelys Garc{\'\i}a-Moreno and Maryam Shojaei Baghini and Antoni Ivorra} } @article {196, title = {Interleaved intramuscular stimulation with minimally overlapping electrodes evokes smooth and fatigue resistant forces}, journal = {Journal of Neural Engineering}, volume = {17}, year = {2020}, pages = {046037}, chapter = {046037}, doi = {10.1088/1741-2552/aba99e}, url = {https://doi.org/10.1088/1741-2552/aba99e}, author = {Ahmed Eladly and Jaume Del Valle and Jesus Minguillon and Borja Mercadal and Laura Becerra-Fajardo and Xavier Navarro and Antoni Ivorra} } @article {194, title = {Monitoring the molecular composition of live cells exposed to electric pulses via label-free optical methods}, journal = {Scientific Reports}, volume = {10}, year = {2020}, pages = {10471}, chapter = {10471}, doi = {10.1038/s41598-020-67402-x}, url = {https://doi.org/10.1038/s41598-020-67402-x}, author = {Antoine Azan and Marianne Grognot and Tomas Garcia-Sanchez and Lucie Descamps and Val{\'e}rie Untereiner and Guilhem Gallot and Lluis M. Mir} } @article {197, title = {Physiological changes may dominate the electrical properties of liver during reversible electroporation: measurements and modelling}, journal = {Bioelectrochemistry}, volume = {(In Press, Journal Pre-proof)}, year = {2020}, doi = {10.1016/j.bioelechem.2020.107627}, url = {https://doi.org/10.1016/j.bioelechem.2020.107627}, author = {Tomas Garcia-Sanchez and Damien Voyer and Clair Poignard and Lluis M. Mir} } @article {191, title = {Possible molecular and cellular mechanisms at the basis of atmospheric electromagnetic field bioeffects}, journal = {International Journal of Biometeorology}, volume = {(In Press, available online)}, year = {2020}, doi = {10.1007/s00484-020-01885-1}, url = {https://doi.org/10.1007/s00484-020-01885-1}, author = {Michal Cifra and Francesca Apollonio and Micaela Liberti and Tomas Garcia-Sanchez and Lluis M. Mir} } @article {189, title = {Power Transfer by Volume Conduction: In Vitro Validated Analytical Models Predict DC Powers above 1 mW in Injectable Implants}, journal = {IEEE Access}, volume = {8}, year = {2020}, pages = {37808-37820}, chapter = {37808}, doi = {10.1109/ACCESS.2020.2975597}, author = {Marc Tudela-Pi and Laura Becerra-Fajardo and Aracelys Garc{\'\i}a-Moreno and Jesus Minguillon and Antoni Ivorra} } @article {195, title = {Pulsed radiofrequency for chronic pain: in vitro evidence of an electroporation mediated calcium uptake}, journal = {Bioelectrochemistry}, volume = {136}, year = {2020}, pages = {107624}, chapter = {107624}, doi = {10.1016/j.bioelechem.2020.107624}, author = {Borja Mercadal and Rub{\'e}n Vicente and Antoni Ivorra} } @article {180, title = {The combination of electroporation and electrolysis (E2) employing different electrode arrays for ablation of large tissue volumes}, journal = {PLoS One}, volume = {14}, year = {2019}, pages = {e0221393}, chapter = {e0221393}, doi = {10.1371/journal.pone.0221393}, url = {https://doi.org/10.1371/journal.pone.0221393}, author = {Nina Klein and Enric Guenther and Florin Botea and Mihail Pautov and Simona Dima and Dana Tomescu and Mihai Popescu and Antoni Ivorra and Michael Stehling and Irinel Popescu} } @article {186, title = {Industrial Electronics for Biomedicine: A New Cancer Treatment Using Electroporation}, journal = {IEEE Industrial Electronics Magazine}, volume = {13}, year = {2019}, pages = {6-18}, chapter = {6}, doi = {10.1109/MIE.2019.2942377}, author = {{\'O}scar Luc{\'\i}a and H{\'e}ctor Sarnago and Tomas Garcia-Sanchez and Lluis M. Mir and Jos{\'e} M. Burd{\'\i}o} } @article {179, title = {Successful tumor Electrochemotherapy using Sine Waves}, journal = {IEEE Transactions on Biomedical Engineering}, volume = {67}, year = {2019}, pages = {1040-1049}, chapter = {1040}, doi = {10.1109/TBME.2019.2928645}, author = {Tomas Garcia-Sanchez and Borja Mercadal and Melanie Polrot and Adeline Muscat and H{\'e}ctor Sarnago and {\'O}scar Luc{\'\i}a and Lluis M. Mir} } @article {169, title = {Avoiding neuromuscular stimulation in liver irreversible electroporation using radiofrequency electric fields}, journal = {Physics in Medicine and Biology}, volume = {63}, year = {2018}, pages = {035027}, chapter = {035027}, doi = {10.1088/1361-6560/aaa16f}, author = {Q. Castellv{\'\i} and Borja Mercadal and Xavier Moll and Fontdevila, Dolors and Andaluz, Anna and Antoni Ivorra} } @article {174, title = {Design, Construction and Validation of an Electrical Impedance Probe with Contact Force and Temperature Sensors Suitable for in-vivo Measurements}, journal = {Scientific Reports}, volume = {8}, year = {2018}, pages = {14818}, chapter = {14818}, doi = {10.1038/s41598-018-33221-4}, author = {A. Ruiz-Vargas and Antoni Ivorra and J. W. Arkwright} } @article {159, title = {Effect of applied voltage, duration and repetition frequency of RF pulses for pain relief on temperature spikes and electrical field: A computer modeling study}, journal = {International Journal of Hyperthermia }, volume = {34}, year = {2018}, pages = {112-121}, chapter = {112}, doi = {10.1080/02656736.2017.1323122}, url = {http://dx.doi.org/10.1080/02656736.2017.1323122}, author = {El{\.z}bieta Ewertowska and Borja Mercadal and V{\'\i}ctor Mu{\~n}oz and Antoni Ivorra and Trujillo, Macarena and Berjano, Enrique} } @conference {173, title = {First Steps Towards an Implantable Electromyography (EMG) Sensor Powered and Controlled by Galvanic Coupling}, booktitle = {World Congress on Medical Physics and Biomedical Engineering 2018. IFMBE Proceedings}, volume = {68/3}, year = {2018}, month = {2019}, pages = {19-22}, publisher = {Springer}, organization = {Springer}, address = {Prague, Czech Republic}, abstract = {

In the past it has been proposed to use implanted electromyography (EMG) sensors for myoelectric control. In contrast to surface systems, these implanted sensors provide signals with low cross-talk. To achieve this, miniature implantable devices that acquire and transmit real-time EMG signals are necessary. We have recently in vivo demonstrated electronic implants for electrical stimulation which can be safely powered and independently addressed by means of galvanic coupling. Since these implants lack bulky components as coils and batteries, we anticipate it will be possible to accomplish very thin implants to be massively deployed in tissues. We have also shown that these devices can have bidirectional communication. The aim of this work is to demonstrate a circuit architecture for embedding EMG sensing capabilities in our galvanically powered implants. The circuit was simulated using intramuscular EMG signals obtained from an analytical infinite volume conductor model that used a similar implant configuration. The simulations showed that the proposed analog front-end is compatible with the galvanic powering scheme and does not affect the implant{\textquoteright}s ability to perform electrical stimulation. The system has a bandwidth of 958 Hz, an amplification gain of 45 dB, and an output-referred noise of 160 {\textmu}Vrms. The proposed embedded EMG sensing capabilities will boost the use of these galvanically powered implants for diagnosis, and closed-loop control.

}, doi = {10.1007/978-981-10-9023-3_4}, author = {Laura Becerra-Fajardo and Antoni Ivorra} } @article {168, title = {Impedance spectroscopy measurements as a tool for distinguishing different luminal content during bolus transit studies}, journal = {Neurogastroenterology and Motility}, volume = {30}, year = {2018}, pages = {e13274}, chapter = {e13274}, doi = {10.1111/nmo.13274}, author = {A. Ruiz-Vargas and R. Mohd Rosli and Antoni Ivorra and J. W. Arkwright} } @article {171, title = {Irreversible electroporation for the treatment of cardiac arrhythmias}, journal = {Expert Review of Cardiovascular Therapy}, volume = {16}, year = {2018}, pages = {349-360 }, chapter = {349}, doi = {10.1080/14779072.2018.1459185}, url = {https://www.tandfonline.com/doi/abs/10.1080/14779072.2018.1459185}, author = {Alan Sugrue and Elad Maor and Antoni Ivorra and Vaibhav Vaidya and Chance Witt and Suraj Kapa and Samuel Asirvatham} } @article {161, title = {Modeling Liver Electrical Conductivity during Hypertonic Injection}, journal = {International Journal for Numerical Methods in Biomedical Engineering}, volume = {34}, year = {2018}, pages = {e2904}, chapter = {e2904}, doi = {10.1002/cnm.2904}, author = {Q. Castellv{\'\i} and Patricia S{\'a}nchez-Vel{\'a}zquez and Xavier Moll and Berjano, Enrique and Andaluz, Anna and Burd{\'\i}o, Fernando and Bijnens, Bart and Antoni Ivorra} } @conference {181, title = {Monitoring the Effect of Contact Pressure on Bioimpedance Measurements}, booktitle = {018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)}, year = {2018}, month = {2019}, pages = {4949-4952}, doi = {10.1109/EMBC.2018.8513173}, author = {A. Ruiz-Vargas and Antoni Ivorra and J. W. Arkwright} } @article {162, title = {Numerical analysis of thermal impact of intramyocardial capillary blood flow during radiofrequency cardiac ablation}, journal = {International Journal of Hyperthermia}, volume = {34}, year = {2018}, pages = {243-249}, chapter = {243}, doi = {10.1080/02656736.2017.1336258}, author = {P{\'e}rez, Juan J. and Gonz{\'a}lez-Su{\'a}rez, Ana and Berjano, Enrique} } @conference {172, title = {Powering Implants by Galvanic Coupling: A Validated Analytical Model Predicts Powers Above 1 mW in Injectable Implants}, booktitle = {World Congress on Medical Physics and Biomedical Engineering 2018. IFMBE Proceedings}, volume = {68/3}, year = {2018}, month = {2019}, pages = {23-26}, publisher = {Springer}, organization = {Springer}, address = {Prague, Czech Republic}, abstract = {

While galvanic coupling for intrabody communications has been proposed lately by different research groups, its use for powering active implantable medical devices remains almost non-existent. Here it is presented a simple analytical model able to estimate the attainable power by galvanic coupling based on the delivery of high frequency (\>1 MHz) electric fields applied as short bursts. The results obtained with the analytical model, which is in vitro validated in the present study, indicate that time-averaged powers above 1 mW can be readily obtained in very thin (diameter \< 1 mm) and short (length \< 20 mm) elongated implants when fields which comply with safety standards (SAR \< 10 W/kg) are present in the tissues where the implants are located. Remarkably, the model indicates that, for a given SAR, the attainable power is independent of the tissue conductivity and of the duration and repetition frequency of the bursts. This study reveals that galvanic coupling is a safe option to power very thin active implants, avoiding bulky components such as coils and batteries.

}, doi = {10.1007/978-981-10-9023-3_5}, author = {Marc Tudela-Pi and Laura Becerra-Fajardo and Antoni Ivorra} } @article {167, title = {Relation between Denaturation Time Measured by Optical Coherence Reflectometry and Thermal Lesion Depth during Radiofrequency Cardiac Ablation: Feasibility Numerical Study}, journal = {Lasers in surgery and medicine}, volume = {50}, year = {2018}, pages = {222-229}, chapter = {222}, doi = {10.1002/lsm.22771}, author = {Gonz{\'a}lez-Su{\'a}rez, Ana and Herranz, David and Berjano, Enrique and Rubio-Guivernau, Jose L and Margallo-Balb{\'a}s, Eduardo} } @article {183, title = {RF-Energized Intracoronary Guidewire to Enhance Bipolar Ablation of the Interventricular Septum: In-silico Feasibility Study}, journal = {International Journal of Hyperthermia}, volume = {34}, year = {2018}, pages = {1202-1212}, chapter = {1202}, doi = {10.1080/02656736.2018.1425487}, url = {https://www.tandfonline.com/doi/full/10.1080/02656736.2018.1425487}, author = {P{\'e}rez, Juan J. and Gonz{\'a}lez-Su{\'a}rez, Ana and d{\textquoteright}Avila, A and Berjano, Enrique} } @article {182, title = {Should fluid dynamics be included in computer models of RF cardiac ablation by irrigated-tip electrodes?}, journal = {BioMedical Engineering OnLine}, volume = {17}, year = {2018}, pages = {43}, chapter = {43}, doi = {10.1186/s12938-018-0475-7}, url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5910590/}, author = {Gonz{\'a}lez-Su{\'a}rez, Ana and P{\'e}rez, Juan J. and Berjano, Enrique} } @conference {175, title = {Two-Port Networks to Model Galvanic Coupling for Intrabody Communications and Power Transfer to Implants}, booktitle = {2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)}, year = {2018}, month = {10/2018}, pages = {407-410}, isbn = {978-1-5386-3603-9}, doi = {10.1109/BIOCAS.2018.8584691}, author = {Laura Becerra-Fajardo and Marc Tudela-Pi and Antoni Ivorra} } @article {153, title = {Anatomically Realistic Simulations of Liver Ablation by Irreversible Electroporation: Impact of Blood Vessels on Ablation Volumes and Undertreatment}, journal = {Technology in Cancer Research \& Treatment}, volume = {[Epub ahead of print]}, year = {2017}, doi = {10.1177/1533034616687477}, author = {Radwan Qasrawi and Louis Silve and Fernando Burd{\'\i}o and Ziad Abdeen and Antoni Ivorra} } @article {165, title = {Avoiding nerve stimulation in irreversible electroporation: a numerical modeling study}, journal = {Physics in Medicine and Biology}, volume = {62}, year = {2017}, pages = {8060-8079}, chapter = {8060}, doi = {https://doi.org/10.1088/1361-6560/aa8c53}, author = {Borja Mercadal and Christopher Arena and Rafael Davalos and Antoni Ivorra} } @article {152, title = {Demonstration of 2 mm thick microcontrolled injectable stimulators based on rectification of high frequency current bursts}, journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering}, volume = {25}, year = {2017}, pages = {1343 - 1352}, chapter = {1343}, doi = {10.1109/TNSRE.2016.2623483}, author = {Laura Becerra-Fajardo and Marieluise Schmidbauer and Antoni Ivorra} } @article {220, title = {Electronic System Having Variable Modular Power for Generating Electrical Pulses and Associated Uses}, year = {2017}, edition = {A61N1/32}, chapter = {WO 2017/109261 A1 }, author = {H{\'e}ctor Sarnago and {\'O}scar Luc{\'\i}a and Jos{\'e} M. Burd{\'\i}o and Alejandro Naval and Antoni Ivorra and Q. Castellv{\'\i}} } @article {166, title = {Focused Transhepatic Electroporation Mediated by Hypersaline Infusion throuth the Portal Vein in Rat Model. Preliminary Results on Differential Conductivity}, journal = {Radiology and Oncology}, volume = {51}, year = {2017}, pages = {415-421}, chapter = {415}, author = {Clara Pa{\~n}ella and Q. Castellv{\'\i} and Xavier Moll and Rita Quesada and Alberto Villanueva and M. Iglesias and Dolores Naranjo and Patricia S{\'a}nchez-Vel{\'a}zquez and Andaluz, Anna and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @conference {156, title = {Injectable Stimulators Based on Rectification of High Frequency Current Bursts: Power Efficiency of 2~mm Thick Prototypes}, booktitle = {Converging Clinical and Engineering Research on Neurorehabilitation II: Proceedings of the 3rd International Conference on NeuroRehabilitation (ICNR2016), October 18-21, 2016, Segovia, Spain}, year = {2017}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, address = {Cham}, abstract = {

To overcome the miniaturization bottleneck imposed by existing power generation/transfer technologies for implantable stimulators, we have proposed a heterodox electrical stimulation method based on local rectification of high frequency (>=1\ MHz) current bursts delivered through superficial electrodes. We have reported 2\ mm thick addressable injectable stimulators, made of off-the-shelf components, that operate according to this principle. Since a significant amount of high frequency power is wasted by Joule heating, the method exhibits poor energy efficiency. In here we have performed a numerical case study in which the presence of the above implant prototypes is simulated in an anatomically realistic leg model. The results from this study indicate that, despite low power transfer efficiency (~0.05\ \%), the power consumed by the external high frequency current generator is low enough (\<4\ W) to grant the use of small portable batteries.

}, isbn = {978-3-319-46669-9}, doi = {10.1007/978-3-319-46669-9_110}, url = {http://dx.doi.org/10.1007/978-3-319-46669-9_110}, author = {Laura Becerra-Fajardo and Garcia-Arnau, Roser and Antoni Ivorra}, editor = {Ib{\'a}{\~n}ez, Jaime and Gonz{\'a}lez-Vargas, Jos{\'e} and Azor{\'\i}n, Jos{\'e} Mar{\'\i}a and Akay, Metin and Pons, Jos{\'e} Luis} } @article {158, title = {Long-term effectiveness of irreversible electroporation in a murine model of colorectal liver metastasis}, journal = {Scientific reports}, volume = {7}, year = {2017}, chapter = {44821}, doi = {10.1038/srep44821}, author = {Patricia S{\'a}nchez-Vel{\'a}zquez and Q. Castellv{\'\i} and Alberto Villanueva and M. Iglesias and Rita Quesada and Clara Pa{\~n}ella and Marta C{\'a}ceres and Dimitri Dorcaratto and Andaluz, Anna and Xavier Moll and Jos{\'e} M. Burd{\'\i}o and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @conference {147, title = {3D Assessment of Irreversible Electroporation Treatments in Vegetal Models}, booktitle = {1st World Congress on Electroporation and Pulsed Electric Fields in Biology, Medicine and Food \& Environmental Technologies}, series = {IFMBE Proceedings}, volume = {53}, year = {2016}, pages = {294-297}, publisher = {Springer Singapore}, organization = {Springer Singapore}, keywords = {In-vivo assessment, Irreversible electroporation, Potato, Three-dimensional, Vegetal model}, isbn = {978-981-287-816-8}, url = {http://dx.doi.org/10.1007/978-981-287-817-5_65}, author = {Q. Castellv{\'\i} and J. Ban{\'u}s and Antoni Ivorra}, editor = {Jarm, Tomaz and Kramar, Peter} } @inbook {155, title = {Assessment of Electroporation by Electrical Impedance Methods}, booktitle = {Handbook of Electroporation}, year = {2016}, pages = {1-20 (electronic)}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, abstract = {

Electroporation causes an immediate increase in cell membrane permeability that results in membrane conductivity increase, which has an effect in the measured impedance of the cell suspension or the tissue. Therefore, impedance measurements offer the possibility to perform real-time assessment of the electroporation phenomenon in a minimally invasive fashion. Nevertheless, impedance measurements in biological organisms depend on many factors and other processes besides the membrane permeabilization. This lack of specificity can be an important drawback for using impedance measurements as an electroporation measure. An equivalent electrical model of cell suspensions and tissues is commonly employed to better understand how the different processes that take place during electroporation can affect the measured impedance of a sample. This chapter briefly overviews the information that can be extracted from impedance measurements during and after the application of electroporation pulses. These measurements have been widely used to observe and analyze the dynamics of the phenomenon. Impedance has the potential to be used as a tool to assess electroporation effectiveness of treatment. A significant conclusion from the experimental studies on the topic is that conductivity measured shortly after treatment appears to be correlated with electroporation effectiveness in terms of cell membrane permeabilization. That is, it has the potential to be used as an electroporation effectiveness indicator. On the other hand, dynamic conductivity during the electroporation pulses, which is much easier to be measured, does not seem to be correlated with electroporation effectiveness.

}, issn = {978-3-319-26779-1}, doi = {10.1007/978-3-319-26779-1_164-1}, author = {Q. Castellv{\'\i} and Borja Mercadal and Antoni Ivorra} } @article {151, title = {Dependence of electroporation detection threshold on cell radius: an explanation to observations non compatible with Schwan{\textquoteright}s equation model}, journal = {Journal of Membrane Biology}, volume = {249}, year = {2016}, pages = {663-676}, chapter = {663}, abstract = {

It is widely accepted that electroporation occurs when the cell transmembrane voltage induced by an external applied electric field reaches a threshold. Under this assumption, in order to trigger electroporation in a spherical cell, Schwan{\textquoteright}s equation leads to an inversely proportional relationship between the cell radius and the minimum magnitude of the applied electric field. And, indeed, several publications report experimental evidences of an inverse relationship between the cell size and the field required to achieve electroporation. However, this dependence is not always observed or is not as steep as predicted by Schwan{\textquoteright}s equation. The present numerical study attempts to explain these observations that do not fit Schwan{\textquoteright}s equation on the basis of the interplay between cell membrane conductivity, permeability and transmembrane voltage. For that, a single cell in suspension was modeled and it was determined the electric field necessary to achieve electroporation with a single pulse according to two effectiveness criteria: a specific permeabilization level, understood as the relative area occupied by the pores during the pulse, and a final intracellular concentration of a molecule due to uptake by diffusion after the pulse, during membrane resealing. The results indicate that plausible model parameters can lead to divergent dependencies of the electric field threshold on the cell radius. These divergent dependencies were obtained through both criteria and using two different permeabilization models. This suggests that the interplay between cell membrane conductivity, permeability and transmembrane voltage might be the cause of results which are non compatible with the Schwan{\textquoteright}s equation model.\ 

}, author = {Borja Mercadal and P. Thomas Vernier and Antoni Ivorra} } @conference {146, title = {Incorporation of the Blood Vessel Wall into Electroporation Simulations}, booktitle = {1st World Congress on Electroporation and Pulsed Electric Fields in Biology, Medicine and Food \& Environmental Technologies}, series = {IFMBE Proceedings}, volume = {53}, year = {2016}, pages = {223-227}, publisher = {Springer Singapore}, organization = {Springer Singapore}, keywords = {Blood vessel, Blood vessel wall, Electric field, Electroporation, Simulation}, isbn = {978-981-287-816-8}, url = {http://dx.doi.org/10.1007/978-981-287-817-5_50}, author = {Louis Silve and Radwan Qasrawi and Antoni Ivorra}, editor = {Jarm, Tomaz and Kramar, Peter} } @article {150, title = {Irreversible electroporation of the liver: is there a safe limit to the ablation volume?}, journal = {Scientific Reports}, volume = {6}, year = {2016}, pages = {23781}, doi = {10.1038/srep23781}, author = {Patricia S{\'a}nchez-Vel{\'a}zquez and Q. Castellv{\'\i} and Alberto Villanueva and Rita Quesada and Clara Pa{\~n}ella and Marta C{\'a}ceres and Dimitri Dorcaratto and Andaluz, Anna and Xavier Moll and Trujillo, Macarena and Jos{\'e} M. Burd{\'\i}o and Berjano, Enrique and Luis Grande and Antoni Ivorra and Burd{\'\i}o, Fernando} } @article {149, title = {A Versatile Multilevel Converter Platform for Cancer Treatment Using Irreversible Electroporation}, journal = {IEEE Journal of Emerging and Selected Topics in Power Electronics}, volume = {4}, year = {2016}, pages = {236 - 242}, chapter = {236}, issn = {2168-6777}, doi = {10.1109/JESTPE.2015.2512324}, author = {H{\'e}ctor Sarnago and {\'O}scar Luc{\'\i}a and Alejandro Naval and Jos{\'e} M. Burd{\'\i}o and Q. Castellv{\'\i} and Antoni Ivorra} } @conference {140, title = {Bidirectional communications in wireless microstimulators based on electronic rectification of epidermically applied currents}, booktitle = {Neural Engineering (NER), 2015 7th International IEEE/EMBS Conference on}, year = {2015}, month = {April}, doi = {10.1109/NER.2015.7146680}, author = {Laura Becerra-Fajardo and Antoni Ivorra} } @conference {132, title = {Charge Counter for Performing Active Charge-Balance in Miniaturized Electrical Stimulators}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering SE - 64}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, month = {2015///}, pages = {256 - 259}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, keywords = {active charge-balance, dc-blocking capacitor, FES, miniaturization, rectifier}, isbn = {978-3-319-11127-8}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_64}, author = {Laura Becerra-Fajardo and Antoni Ivorra}, editor = {Lackovi{\'c}, Igor and Vasic, Darko} } @conference {139, title = {Impact of Liver Vasculature on Electric Field Distribution during Electroporation Treatments: An Anatomically Realistic Numerical Study}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, pages = {573-576}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, keywords = {blood vessels, conductivity, Electroporation, numerical modeling}, isbn = {978-3-319-11127-8}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_143}, author = {Radwan Qasrawi and Antoni Ivorra}, editor = {Lackovi{\'c}, Igor and Vasic, Darko} } @article {138, title = {In Vivo Demonstration of Addressable Microstimulators Powered by Rectification of Epidermically Applied Currents for Miniaturized Neuroprostheses}, journal = {Plos One}, volume = {10}, year = {2015}, month = {07/2015}, chapter = {e0131666}, doi = {10.1371/journal.pone.0131666}, url = {http://dx.doi.org/10.1371\%2Fjournal.pone.0131666}, author = {Laura Becerra-Fajardo and Antoni Ivorra} } @article {144, title = {In vivo demonstration of injectable microstimulators based on charge-balanced rectification of epidermically applied currents}, journal = {Journal of Neural Engineering}, volume = {12}, year = {2015}, chapter = {066010}, doi = {10.1088/1741-2560/12/6/066010}, author = {Antoni Ivorra and Laura Becerra-Fajardo and Q. Castellv{\'\i}} } @conference {133, title = {Selective Electroporation of Liver Tumor Nodules by Means of Hypersaline Infusion: A Feasibility Study}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, pages = {821-824}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, abstract = {

Spread tumors in liver are not suitable to be treated with local treatments, such as conventional surgery or radiofrequency ablation, thus entailing a poor prognosis. Electroporation-based therapies imply the delivery of pulsed high electric fields and currently are performed in a local fashion using needle or plate electrodes. Here, however, it is proposed a novel electroporation paradigm in which field delivery is not local. All the tumor nodules will be selectively treated using large plate electrodes at both sides of the liver. By infusing an hypersaline solution of high electrical conductivity through the portal vein, the electrical conductivity of healthy tissues and tumor nodules will be made significantly different so that the electric field will be focused on the undesirable tissues. Numerical simulations were used to evaluate the feasibility of the proposed technique. In addition, an in vivo procedure was carried out to assess whether it is possible and practical to significantly modify the conductivity of the liver tissue by hypersaline infusion. Both the numerical simulations and the in vivo procedure provided encouraging results.

}, keywords = {Disseminated nodules, Electroporation, Hypersaline, Liver, Spread tumors}, isbn = {978-3-319-11127-8}, doi = {10.1007/978-3-319-11128-5_204}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_204}, author = {Q. Castellv{\'\i} and Patricia S{\'a}nchez-Vel{\'a}zquez and Berjano, Enrique and Burd{\'\i}o, Fernando and Antoni Ivorra} } @article {137, title = {Tumor growth delay by adjuvant alternating electric fields which appears non-thermally mediated}, journal = {Bioelectrochemistry}, volume = {105}, year = {2015}, month = {2015/10//}, pages = {16 - 24}, keywords = {Alternating electric field, Chemotherapeutic adjuvant, Hyperthermia, Pancreatic tumor, TTFields}, isbn = {1567-5394}, doi = {10.1016/j.bioelechem.2015.04.006}, author = {Q. Castellv{\'\i} and Mireia M. Ginest{\`a} and G. Capella and Antoni Ivorra} } @article {134, title = {Bioimpedance Measurements and the Electroporation Phenomenon}, journal = {Revue 3EI}, volume = {75}, year = {2014}, month = {04/2014}, pages = {21-26}, abstract = {

Bioimpedance measurements are used to determine physiological aspects of biological tissues. On the other hand, the electroporation phenomenon causes a variation in the electrical properties of tissue, so it is possible use bioimpedance measurement with the aim of monitor the electroporation phenomenon in real time. The objective of this article is present the basic concepts required to understand bioimpedance measurements and the utility of these for detecting the electroporation effects.

}, author = {Q. Castellv{\'\i}} } @article {141, title = {Comparison of the effects of the repetition rate between microsecond and nanosecond pulses: Electropermeabilization-induced electro-desensitization?}, journal = {Biochimica et Biophysica Acta (BBA) - General Subjects}, volume = {1840}, year = {2014}, pages = {2139 - 2151}, keywords = {Electroporation}, issn = {0304-4165}, doi = {http://dx.doi.org/10.1016/j.bbagen.2014.02.011}, url = {http://www.sciencedirect.com/science/article/pii/S0304416514000725}, author = {Aude Silve and A. Guimer{\`a} Brunet and B. Al-Sakere and Antoni Ivorra and L.M. Mir} } @article {Gonzalez-Sosa2014, title = {{Fast flow-through non-thermal pasteurization using constant radiofrequency electric fields}}, journal = {Innovative Food Science and Emerging Technologies}, volume = {22}, year = {2014}, pages = {pp.116-123}, chapter = {116}, doi = {DOI: 10.1016/j.ifset.2014.01.003}, author = {J. Gonz{\'a}lez-Sosa and A. Ruiz-Vargas and G. Arias and Antoni Ivorra} } @conference {190, title = {Flexible Thread-like Electrical Stimulation Implants Based on Rectification of Epidermically Applied Currents which Perform Charge Balance}, booktitle = {2nd International Conference on NeuroRehabilitation (ICNR2014), Aalborg, 24-26 June, 2014}, year = {2014}, pages = {447-455}, publisher = {Springer}, organization = {Springer}, address = {Aalborg, Denmark}, isbn = {978-3-319-08072-7}, doi = {10.1007/978-3-319-08072-7_67}, author = {Antoni Ivorra and Laura Becerra-Fajardo} } @article {Ivorra, title = {System for preventing bacterial infections in needle trajectories}, number = {P201231644}, year = {2014}, month = {10/2012}, type = {Granted}, edition = {A61b18/14; A61B10/02}, chapter = {WO 2014/064304 A1}, address = {Spain}, author = {Antoni Ivorra and Q. Castellv{\'\i}} } @conference {131, title = {Towards addressable wireless microstimulators based on electronic rectification of epidermically applied currents}, booktitle = {Annual International Conference of the IEEE Engineering in Medicine and Biology Society}, year = {2014}, month = {2014///}, pages = {3973 - 3976}, publisher = {IEEE}, organization = {IEEE}, address = {Chicago}, abstract = {

Electrical stimulation has been explored to restore the capabilities of the nervous system in paralysis patients. This area of research and of clinical practice, known as Functional Electrical Stimulation, would greatly benefit from further miniaturization of implantable stimulators. To that end, we recently proposed and demonstrated an innovative electrical stimulation method in which implanted microstimulators operate as rectifiers of bursts of innocuous high frequency current supplied by skin electrodes, thus generating low frequency currents capable of stimulating excitable tissues. A diode could suffice in some applications but, in order to broaden the method{\textquoteright}s clinical applicability, we envision rectifiers with advanced capabilities such as current control and addressability. We plan flexible thread-like implants (diameters \< 300 urn) containing ASICs. As an intermediate stage, we are developing macroscopic implants (diameters \~{} 2 mm) made of off-the-shelf components. Here we present a circuit which responds to commands modulated within the high frequency bursts and which is able to deliver charge-balanced currents. We show that a number of these circuits can perform independent stimulation of segments of an anesthetized earthworm following commands from a computer.

}, keywords = {Batteries, Capacitors, Electrical Stimulation, Electrodes, Implants, Microcontrollers, Rectifiers}, author = {Laura Becerra-Fajardo and Antoni Ivorra} } @article {Trujillo2013, title = {{Can electroporation previous to radiofrequency hepatic ablation enlarge thermal lesion size? A feasibility study based on theoretical modelling and in vivo experiments.}}, journal = {International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group}, volume = {29}, number = {3}, year = {2013}, pages = {211{\textendash}8. {\textcopyright} 2013 Informa UK Ltd.}, abstract = {

PURPOSE: The aim of this study was to assess the feasibility of a hybrid ablative technique based on applying electroporation (EP) pulses just before conducting radiofrequency ablation (RFA). The rationale was that the EP-induced reduction in blood perfusion could be sufficient to reduce the thermal sink effect and hence to increase the coagulation volume in comparison to that created exclusively by RFA. MATERIALS AND METHODS: A modelling study and in vivo experimental study were used. A Cool-tip RF applicator was used both for EP and RFA. RESULTS: Overall, the results did not show any synergy effect from using the hybrid technique. Applying EP pulses prior to RFA did not increase the coagulation zone obtained and the lesions were almost identical. Additional computer simulations provided an explanation for this; the effect of reducing blood perfusion by thermal damage during RFA completely masks the effect of reducing blood perfusion by EP. This is because both thermal damage and EP affect the same zone, i.e. the tissue around the electrode. CONCLUSIONS: Our computer modelling and in vivo experimental findings suggest that the combination of EP and RFA with monopolar applicators does not provide an additional benefit over the use of RFA alone.

}, keywords = {Animals, Catheter Ablation, Combined Modality Therapy, Computer Simulation, Electroporation, Feasibility Studies, Female, Liver, Liver: surgery, Models, Swine, Theoretical}, issn = {1464-5157}, doi = {10.3109/02656736.2013.777854}, url = {http://www.ncbi.nlm.nih.gov/pubmed/23573935}, author = {Trujillo, Macarena and Q. Castellv{\'\i} and Burd{\'\i}o, Fernando and Patricia S{\'a}nchez-Vel{\'a}zquez and Antoni Ivorra and Andaluz, Anna and Berjano, Enrique} } @conference {Gonzalez-Sosa2013, title = {{Fast flow-through non-thermal pasteurization using constant radiofrequency electric fields}}, booktitle = {Tenth International Bioelectrics Symposium (BIOELECTRICS 2013)}, year = {2013}, address = {Karlsruhe, Germany}, abstract = {

Pulsed Electric Field technologies have captured the attention of researchers on food pasteurization because of their non-thermal inactivation mechanism, which results in fresh-like products. Nevertheless, high voltage pulsing required by these technologies implies complex and costly generators. Here, as an alternative, it is proposed a method, partially inherited from research on cell electroporation for gene transfection, in which the liquid to be treated flows at high speed through a miniature chamber where the electric field is permanently applied. In particular, it is proposed that the constantly applied electric field consists of an AC signal (\> 100 kHz) so that electrochemical by-products are minimized. The method, while being compatible with batch processing, will allow use of lower voltages and will avoid the pulsation requirement.\ 

}, author = {J. Gonz{\'a}lez-Sosa and A. Ruiz-Vargas and G. Arias and Q. Castellv{\'\i} and Antoni Ivorra} } @article {142, title = {In vivo assessment of corneal barrier function through non-invasive impedance measurements using a flexible probe}, journal = {Journal of Physics: Conference Series}, volume = {434}, year = {2013}, pages = {012072}, abstract = {

The cornea is a transparent structure composed of three layers: the epithelium, the stroma and the endothelium. To maintain its ransparency the stroma remains in a constant state of dehydration. Consequently, any ion flow disorder through the covering layers can compromise the barrier function and, therefore the corneal homeostasis. Since ionic permeability has a fundamental impact on the passive electrical properties of living tissues, in this work it is proposed and demonstrated a diagnosis method based on tetrapolar impedance measurements performed by electrodes placed on the corneal surface. The contribution of each cornea layer to the total measured impedance has been analysed over a frequency range. Following the obtained guidelines, a flexible probe with integrated electrodes has been developed and manufactured using SU-8 photoresin. The feasibility of the proposed method has been evaluated in vivo by monitoring corneal epithelium wound healing. Obtained impedance measurements have been compared with measurements of permeability to sodium fluorescein from different excised corneas. Successful results demonstrate the feasibility of this novel flexible sensor and its capability to quantify corneal permeability in vivo in a noninvasive way.

}, url = {http://stacks.iop.org/1742-6596/434/i=1/a=012072}, author = {A Guimera and X Illa and E Traver and S Marchan and C Herrero and C Lagunas and M J Maldonado and Antoni Ivorra and R Villa} } @conference {Castellvi2013, title = {{In vivo study using Tumor Treatment Fields (TTFs) and prolonged mild hyperthermia as adjuvant methods for cancer treatment}}, booktitle = {Tenth International Bioelectrics Symposium (BIOELECTRICS 2013)}, year = {2013}, address = {Karlsruhe, Germany}, abstract = {

Delivery of the so called Tumor Treatment Fields (TTFs) was proposed a few years ago as a cancer therapy and has been object of study in a recent phase III trial in which their efficacy against glioblastomas was assessed with modest results [1]. TTFs are alternating electric fields at a frequency in the order of 100 kHz and a magnitude below 300 V/m which are applied continuously for weeks. According to their proposers, TTFs inhibit tumor growth by interfering with the cell division process through electrical forces without causing significant heating in tissues. However, we estimate that TTFs are capable of producing temperature increases of about some tens of kelvin which cannot be neglected, particularly because TTFs are applied for long periods of time. Therefore, we hypothesized that the promising results reported in initial in vitro and in vivo studies on the use of TTFs could be mediated by heat rather than by electrical forces. Heat induction (i.e. hyperthermia) has been extensively used as an adjuvant in cancer treatment. Typically, cancer hyperthermia involves generating moderate temperature increases during about one hour after radiotherapy or chemotherapy sessions. Nevertheless, to the best of our knowledge, there are no in vivo studies on the use of mild hyperthermia for long periods of time, despite there are in vitro studies showing that cell survival to hyperthermia depends both on the temperature and the exposition time. In order to test our hypothesis and also to independently validate the efficacy of TTFs, we have carried out a study in which nude mice subcutaneously implanted with human exocrine pancreatic adenocarcinomas were physically treated for 7 days; either with heat from a resistor or with TTFs delivered by electrodes. The animals were paired: one was treated and the other was sham treated. Four treatment groups were created: hyperthermia (H) (n=5+5), hyperthermia + gemcitabine chemotherapy (H\&Ch) (n=6+6), TTFs (TTF) (n=5+5) and TTFs + gemcitabine therapy (TTF\&Ch) (n=7+7). Our hypothesis has not been validated: no statistically significant effects were observed in the H and H\&Ch groups. On the other hand, although the TTF group did also not produce any significant effect, the animals treated with the TTFs + chemotherapy combination show a tumor growth rate about 200\% smaller (p=0.018) than the animals treated only with chemotherapy.

}, author = {Q. Castellv{\'\i} and Mireia M. Ginest{\`a} and G. Capella and Antoni Ivorra} } @conference {Ivorra2013, title = {Wireless Microstimulators Based on Electronic Rectification of Epidermically Applied Currents: Safety and Portability Analysis}, booktitle = {18th IFESS Annual Conference}, year = {2013}, pages = {213{\textendash}216}, address = {Donostia-San Sebasti{\'a}n, Spain}, abstract = {

Miniaturization of implantable medical electronic devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants {\textendash} batteries and inductive couplers {\textendash} comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. For overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, we recently proposed and demonstrated a method in which the implants operate as rectifiers of bursts of high frequency (HF) current supplied by remote electrodes. In this way, low frequency currents capable of performing stimulation of excitable tissues are generated locally around the implants whereas the auxiliary high frequency currents only cause innocuous heating. This approach has the potential to reduce the diameter of the implants to one-tenth the diameter of current microstimulators and, more importantly, to allow that most of the implants{\textquoteright} volume consists of flexible materials. Implants based on the proposed method may look like short pieces of flexible thread. With currently available microelectronic techniques, diameters down to 200 $μ$m are easily conceivable. The numerical study presented here, in which a hypothetical but plausible clinical scenario for paralysis is analyzed, shows that the auxiliary high frequency (1 MHz) currents will be indeed safe according to safety standards and that portable systems based on portable batteries will be feasible.

}, author = {Antoni Ivorra and Laura Becerra-Fajardo} } @conference {Ivorra2012, title = {{Injectable Rectifiers as Microdevices for Remote Electrical Stimulation: an Alternative to Inductive Coupling}}, booktitle = {World Congress 2012 on Medical Physics and Biomedical Engineering}, year = {2012}, pages = {1581{\textendash}1584}, address = {Beijing, China}, abstract = {

Miniaturization of implantable medical electronic devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants {\textendash} batteries and inductive couplers {\textendash} comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. For overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, we recently proposed and demonstrated a method based on making the implants operate as rectifiers of bursts of high frequency current supplied by remote electrodes. In this way, low frequency current is generated locally around the implant and this low frequency current performs stimulation of excitable tissues whereas the high frequency current only causes innocuous heating. The present paper reports further progress in this technology. We first describe construction and functional test of an injectable stimulator consisting of a single miniature diode (300 m {\texttimes} 300 m {\texttimes} 600 m) and two thin electrodes which is implanted trough a 19G needle into an anesthetized earthworm. We then propose a circuit architecture for implementing smart implants based on this technology. Both accomplishments are steps towards the implementation of injectable addressable microsystems for neuroprosthetics. These systems based on the proposed technology will look like short pieces of flexible thread rather than rigid capsules, as it was the case of previous miniature electrical stimulation implants. With currently available microelectronic techniques, very thin stimulation implants (diameter \< 200 m) are easily conceivable. This technology may be foundational to a broad range of new developments in the field of implantable medical devices with applications ranging from wound healing to nerve stimulation for pain relief. In addition, other non-medical devices could also emerge such as implantable identification devices.

}, keywords = {Electrical Stimulation, Implantable Devices, Microsystems, Neuroprosthetics, Rectifiers}, author = {Antoni Ivorra and Sacrist{\'a}n, J. and Baldi, A.} } @article {Jose2012, title = {{Irreversible electroporation shows efficacy against pancreatic carcinoma without systemic toxicity in mouse models.}}, journal = {Cancer letters}, volume = {317}, number = {1}, year = {2012}, pages = {16{\textendash}23}, abstract = {

Pancreatic ductal adenocarcinoma (PDAC) therapies show limited success. Irreversible electroporation (IRE) is an innovative loco-regional therapy in which high-voltage pulses are applied to induce plasma membrane defects leading to cellular death. In the present study we evaluated the feasibility of IRE against PDAC. IRE treatment exhibited significant antitumor effects and prolonged survival in mice with orthotopic xenografts. Extensive tumor necrosis, reduced tumor cell proliferation and disruption of microvessels were observed at different days post-IRE. Animals had transient increases in transaminases, amylase and lipase enzymes that normalized at 24h post-IRE. These results suggest that IRE could be an effective treatment for locally advanced pancreatic tumors.

}, keywords = {Alanine Transaminase, Alanine Transaminase: blood, Amylases, Amylases: blood, Animals, Aspartate Aminotransferases, Aspartate Aminotransferases: blood, Biological Markers, Biological Markers: blood, Blood Glucose, Blood Glucose: metabolism, Carcinoma, Cell Line, Cell Proliferation, Electrochemotherapy, Electrochemotherapy: adverse effects, Feasibility Studies, Genes, Humans, Lipase, Lipase: blood, Luminescent Measurements, Male, Mice, Microvessels, Microvessels: pathology, Necrosis, Nude, Pancreatic Ductal, Pancreatic Ductal: blood, Pancreatic Ductal: blood supply, Pancreatic Ductal: genetics, Pancreatic Ductal: pathology, Pancreatic Ductal: therapy, Pancreatic Neoplasms, Pancreatic Neoplasms: blood, Pancreatic Neoplasms: blood supply, Pancreatic Neoplasms: genetics, Pancreatic Neoplasms: pathology, Pancreatic Neoplasms: therapy, Reporter, Time Factors, Transfection, Tumor, Xenograft Model Antitumor Assays}, issn = {1872-7980}, doi = {10.1016/j.canlet.2011.11.004}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22079741}, author = {Jos{\'e}, Anabel and Sobrevals, Luciano and Antoni Ivorra and Fillat, Cristina} } @conference {Becerra-Fajardo2012, title = {{Proof of Concept of a Stimulator Based on AC Current Rectification for Neuroprosthetics}}, booktitle = {XXX Congreso Anual de la Sociedad Espa{\~n}ola de Ingenir{\'\i}a Biom{\'e}dica}, year = {2012}, address = {San Sebasti{\'a}n, Spain}, abstract = {

For several years, researchers have developed techniques to replace and enhance the capabilities of our neural system by means of implantable electrical stimulation technologies. Even though important work has been done in this field, further progress must be accomplished in terms of miniaturization in order to ensure comfort, simpler surgical implantation procedures, and the capability of using multiple wireless smart stimulators for achieving more muscle recruitment. In the past, with the objective of accomplishing an unprecedented level of miniaturization, we have proposed the development of implantable stimulators that would act as rectifiers of AC current supplied by external electrodes. Here it is described the development and evaluation of an addressable stimulator based on discrete component technology as a proof-of-concept of the proposed method. This macroscopic version of the stimulator is capable of generating magnitude controlled bipolar pulses according to commands modulated in the AC current. Multiple evaluations were done to test the device, including DC current testing, in-vitro and in-vivo testing, concluding that the developed system is an effective proof-of-concept of the method proposed, being able to perform controlled electrical stimulation. Electrical current testing showed that anodal and cathodal currents were generated, and in-vivo testing showed the effective electrical stimulation of an anesthetized earthworm. It is concluded that the idea of developing smart rectifiers as implantable stimulators is feasible. This represents a first step towards the design of an implantable device with a miniaturization level without precedents.

}, author = {Laura Becerra-Fajardo and Antoni Ivorra} } @article {Ivorraa, title = {System for the Electrochemical Prevention of Needle Tract Tumor Seeding and Method for Using the System}, number = {P201031848}, year = {2012}, month = {12/2010}, edition = {A61B18/14; A61B10/02; A61B18/12}, chapter = {WO 2012/080394 A1}, address = {Spain}, author = {Antoni Ivorra} } @conference {Silve2011, title = {{Detection of permeabilisation obtained by micropulses and nanopulses by means of bioimpedance of biological tissues}}, booktitle = {5th European Conference on Antennas and Propagation (EUCAP)}, year = {2011}, pages = {3164{\textendash}3167. {\textcopyright} 2011 Institute of Electrical and Electronics Engineers, Inc.}, address = {Rome, Italy}, abstract = {

In this paper permeabilisation of potato tissue caused by either microsecond electric pulses or nanosecond electric pulses is compared. The intensity of permeabilisation is quantified by means of bio-impedance change. Thanks to this method, the impact of the repetition frequency was investigated. Data show that very low repetition frequencies can be much more efficient to permeabilise.

}, author = {Aude Silve and Antoni Ivorra and L.M. Mir} } @article {Ivorra2011, title = {{Electrochemical prevention of needle-tract seeding.}}, journal = {Annals of biomedical engineering}, volume = {39}, number = {7}, year = {2011}, month = {jul}, pages = {2080{\textendash}9}, abstract = {

Needle-tract seeding refers to the implantation of tumor cells by contamination when instruments, such as biopsy needles, are employed to examine, excise, or ablate a tumor. The incidence of this iatrogenic phenomenon is low but it entails serious consequences. Here, as a new method for preventing neoplasm seeding, it is proposed to cause electrochemical reactions at the instrument surface so that a toxic microenvironment is formed. In particular, the instrument shaft would act as the cathode, and the tissues would act as the electrolyte in an electrolysis cell. By employing numerical models and experimental observations reported by researchers on Electrochemical Treatment of tumors, it is numerically showed that a sufficiently toxic environment of supraphysiological pH can be created in a few seconds without excessive heating. Then, by employing an ex vivo model consisting of meat pieces, validity of the conclusions provided by the numerical model concerning pH evolution is confirmed. Furthermore, a simplified in vitro model based on bacteria, instead of tumor cells, is implemented for showing the plausibility of the method. Depending on the geometry of the instrument, suitable current densities will probably range from about 5 to 200 mA/cm(2), and the duration of DC current delivery will range from a few seconds to a few minutes.

}, keywords = {Animals, Electrochemistry, Electrochemistry: methods, Equipment Contamination, Equipment Contamination: prevention \& control, Humans, Needles, Neoplasm Seeding, Neoplasms, Neoplasms: etiology, Neoplasms: prevention \& control}, issn = {1573-9686}, doi = {10.1007/s10439-011-0295-4}, url = {http://www.ncbi.nlm.nih.gov/pubmed/21400019}, author = {Antoni Ivorra} } @article {Ivorra2011a, title = {{Remote electrical stimulation by means of implanted rectifiers.}}, journal = {PloS one}, volume = {6}, number = {8}, year = {2011}, pages = {e23456}, abstract = {

Miniaturization of active implantable medical devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants{\textendash}batteries and inductive couplers{\textendash}comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. Here, for overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, it is proposed to make those implants act as rectifiers of high frequency bursts supplied by remote electrodes. In this way, low frequency currents will be generated locally around the implant and these low frequency currents will perform stimulation of excitable tissues whereas the high frequency currents will cause only innocuous heating. The present study numerically demonstrates that low frequency currents capable of stimulation can be produced by a miniature device behaving as a diode when high frequency currents, neither capable of thermal damage nor of stimulation, flow through the tissue where the device is implanted. Moreover, experimental evidence is provided by an in vivo proof of concept model consisting of an anesthetized earthworm in which a commercial diode was implanted. With currently available microelectronic techniques, very thin stimulation capsules (diameter \<500 {\textmu}m) deliverable by injection are easily conceivable.

}, keywords = {Animals, Electric Stimulation, Electric Stimulation: instrumentation, Electric Stimulation: methods, Electrodes, Implanted, Oligochaeta, Software}, issn = {1932-6203}, doi = {10.1371/journal.pone.0023456}, url = {http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=3151300\&tool=pmcentrez\&rendertype=abstract}, author = {Antoni Ivorra} } @article {Ivorra2010a, title = {{Electric field redistribution during tissue electroporation: its potential impact on treatment planning}}, journal = {Comptes Rendus Physique}, volume = {Accepted (still pending publication)}, year = {2010}, abstract = {
Electroporation is the phenomenon in which cell membrane permeability is increased by exposing the cell to short high electric field pulses. Electroporation is accompanied by an increase of tissue electrical conductivity during the pulses. Such conductivity increase results in a redistribution of the electric field magnitude that can be simulated with simple functions describing the change in tissue conductivity. Experiments on potato tuber reveal that the conductivity increase phenomenon has indeed a significant impact on field distribution, and validate the use of models that take into account such conductivity alteration. For instance, the error in electroporated area estimation can decrease from 30 \% to 3 \%.\ 
}, author = {Antoni Ivorra and Boris Rubinsky and L.M. Mir} } @article {Laufer2010, title = {{Electrical impedance characterization of normal and cancerous human hepatic tissue.}}, journal = {Physiological measurement}, volume = {31}, number = {7}, year = {2010}, pages = {995{\textendash}1009. {\textcopyright} 2010 Institute of Physics and IOP Publishing Limited.}, abstract = {

The four-electrode method was used to measure the ex vivo complex electrical impedance of tissues from 14 hepatic tumors and the surrounding normal liver from six patients. Measurements were done in the frequency range 1-400 kHz. It was found that the conductivity of the tumor tissue was much higher than that of the normal liver tissue in this frequency range (from 0.14 +/- 0.06 S m(-1) versus 0.03 +/- 0.01 S m(-1) at 1 kHz to 0.25 +/- 0.06 S m(-1) versus 0.15 +/- 0.03 S m(-1) at 400 kHz). The Cole-Cole models were estimated from the experimental data and the four parameters (rho(0), rho(infinity), alpha, f(c)) were obtained using a least-squares fit algorithm. The Cole-Cole parameters for the cancerous and normal liver are 9 +/- 4 Omega m(-1), 2.2 +/- 0.7 Omega m(-1), 0.5 +/- 0.2, 140 +/- 103 kHz and 50 +/- 28 Omega m(-1), 3.2 +/- 0.6 Omega m(-1), 0.64 +/- 0.04, 10 +/- 7 kHz, respectively. These data can contribute to developing bioelectric applications for tissue diagnostics and in tissue treatment planning with electrical fields such as radiofrequency tissue ablation, electrochemotherapy and gene therapy with reversible electroporation, nanoscale pulsing and irreversible electroporation.

}, keywords = {80 and over, Adult, Aged, Electric Impedance, Electrodes, Female, Humans, Liver, Liver Cirrhosis, Liver Cirrhosis: pathology, Liver Neoplasms, Liver Neoplasms: pathology, Liver: pathology, Male, Middle Aged}, issn = {1361-6579}, doi = {10.1088/0967-3334/31/7/009}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20577035}, author = {Laufer, Shlomi and Antoni Ivorra and Reuter, Victor E and Boris Rubinsky and Solomon, Stephen B} } @article {Ivorra2010, title = {{Electrical modeling of the influence of medium conductivity on electroporation.}}, journal = {Physical chemistry chemical physics : PCCP}, volume = {12}, number = {34}, year = {2010}, pages = {10055{\textendash}64}, abstract = {

Electroporation is the phenomenon in which cell membrane permeability is increased by exposing the cell to short high electric field pulses. Experimental data show that the amount of permeabilization depends on the conductivity of the extracellular medium. If medium conductivity decreases then it is necessary to deliver a pulse of larger field amplitude in order to achieve the same effect. Models that do not take into account the permeabilization effect on the membrane conductivity cannot reproduce qualitatively the experimental observations. Here we employ an exponential function for describing the strong dependence of membrane conductivity on transmembrane potential. Combining that model with numerical methods we demonstrate that the dependence on medium conductivity can be explained as being the result of increased membrane conductance due to electroporation. As experimentally observed, extracellular conductivities of about 1 and 0.1 S m(-1) yield very similar results, however, for lower conductivities (\<0.01 S m(-1)) the model predicts that significantly higher field magnitudes will be required to achieve the same amount of permeabilization.

}, keywords = {Biological, Cell Membrane, Cell Membrane Permeability, Cell Membrane: metabolism, Diffusion, Electric Conductivity, Electroporation, Membrane Potentials, Models, Reproducibility of Results}, issn = {1463-9084}, doi = {10.1039/c004419a}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20585676}, author = {Antoni Ivorra and J. Villemejane and L.M. Mir} } @inbook {Ivorra2010e, title = {{Historical Review of Irreversible Electroporation in Medicine}}, booktitle = {Irreversible Electroporation}, series = {Series in Biomedical Engineering}, year = {2010}, pages = {1{\textendash}21}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

The objective of this chapter is to present a historical review of the field of irreversible electroporation (IRE) in the context of its medical applications. Although relevant scientific observations were made since the 18th century, the electroporation phenomenon was not identified as an increase of membrane permeability until mid 20th century. After that, multiple applications of reversible electroporation emerged in vitro (DNA electrotransfer) and in vivo (electrogenetherapy and electrochemotherapy). Irreversible electroporation was tested commercially in the 60s as a bactericidal method for liquids and foods but its use in the context of medical applications was not studied until the early 2000s as an ablative method. The cell destruction mechanism of IRE is not based on thermal damage and this fact provides to IRE an important advantage over other physical ablation methods: the extracellular scaffolding, including the vessels, is preserved. Several surgical applications are now under study or even under clinical trial: ablation of hepatocarcinomas, ablation of prostate tumors, treatment of atrial fibrillation and treatment of vascular occurrences such as restenosis and atherosclerotic processes.

}, isbn = {978-3-642-05419-8}, doi = {10.1007/978-3-642-05420-4}, url = {http://link.springer.com/10.1007/978-3-642-05420-4}, author = {Antoni Ivorra and Boris Rubinsky}, editor = {Boris Rubinsky} } @conference {Ivorra2010c, title = {{Introduction to tissue Irreversible Electroporation and effects of electroporation on tissue passive electrical properties}}, booktitle = {Bioelectrochemistry Gordon Research Conference}, year = {2010}, address = {Biddeford, Maine, USA}, author = {Antoni Ivorra} } @inbook {Ivorra2010d, title = {{Irreversible Electroporation}}, booktitle = {Irreversible Electroporation}, series = {Series in Biomedical Engineering}, year = {2010}, pages = {23{\textendash}61}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

Electroporation is the phenomenon in which cell membrane permeability to ions and macromolecules is increased by exposing the cell to short (microsecond to millisecond) high electric field pulses. In living tissues, such permeabilization boost can be used in order to enhance the penetration of drugs (electrochemotherapy) or DNA plasmids (electrogenetherapy) or to destroy undesirable cells (irreversible electroporation). The main purpose of the present chapter is to provide an overview of the electrical concepts related to electroporation for those not familiar with electromagnetism. It is explained that electroporation is a dynamic phenomenon that depends on the local transmembrane voltage and it is shown how a voltage difference applied though a pair of electrodes generates an electric field which in turn induces the required transmembrane voltage for electroporation to occur. Quite exhaustive details are given on how electroporation changes the passive electrical properties of living tissues. Furthermore, some remarks are given about the effects of electroporation on other bioelectric phenomena such as cardiac arrhythmias.

}, isbn = {978-3-642-05419-8}, doi = {10.1007/978-3-642-05420-4}, url = {http://link.springer.com/10.1007/978-3-642-05420-4}, author = {Antoni Ivorra}, editor = {Boris Rubinsky} } @conference {Ivorra2010b, title = {{Irreversible Electroporation for Tissue Ablation}}, booktitle = {5th Course ("Medical Applications of Electromagnetic Fields: Research and Therapy") of the School of Bioelectromagnetism Alessadro Chiabreara}, year = {2010}, author = {Antoni Ivorra} } @inbook {Silve2010, title = {{Nanosecond pulsed electric field delivery to biological samples: difficulties and potential solutions}}, booktitle = {Advanced Electroporation Techniques in Biology and Medicine}, year = {2010}, pages = {353{\textendash}370}, abstract = {

In this chapter we discuss particular features of the nanosecond electric pulsed fields (nsPEFs) that must be taken into account when experimenting on their delivery to biological samples. The purpose of the chapter is to provide future users of this technology with some advice on how to correctly apply it. It is first analyzed how propagation related phenomena can impact on the actual electric field pulse that is applied to the sample. In particular, it is shown that impedance matching for the exposure chamber will be a key element. It is then proposed to employ monitoring systems for voltage and current signals and some indications about their use and limitations are given. Finally, the electrochemical and thermal consequences of nsPEFs delivery are also discussed. We conclude that only excellent experimental conditions can result in robust, controlled and reproducible data on the nsPEFs biological effects.

}, keywords = {breakdown of dielectric, electrochemical reactions, impedance, matching, materials, monitoring, nanosecond electric pulses, thermal effects, transmission line, waves propagation}, isbn = {978-1-439-81906-7}, author = {Aude Silve and J. Villemejane and Joubert, V. and Antoni Ivorra and L.M. Mir} } @article {Guimera2010, title = {{Non-invasive assessment of corneal endothelial permeability by means of electrical impedance measurements.}}, journal = {Medical engineering \& physics}, volume = {32}, number = {10}, year = {2010}, pages = {1107{\textendash}15. {\textcopyright} 2010 IPEM. Published by Elsevier Ltd.}, abstract = {

The permeability of the corneal endothelial layer has an important role in the correct function of the cornea. Since ionic permeability has a fundamental impact on the passive electrical properties of living tissues, here it is hypothesized that impedance methods can be employed for assessing the permeability of the endothelial layer in a minimally invasive fashion. Precisely, the main objective of the present study is to develop and to analyze a minimally invasive method for assessing the electrical properties of the corneal endothelium, as a possible diagnostic tool for the evaluation of patients with endothelial dysfunction. A bidimensional model consisting of the main corneal layers and a four-electrode impedance measurement setup placed on the epithelium has been implemented and analyzed by means of the finite elements method (FEM). In order to obtain a robust indicator of the permeability of the endothelium layer, the effect of the endothelium electrical properties on the measured impedance has been studied together with reasonable variations of the other model layers. Simulation results show that the impedance measurements by means of external electrodes are indeed sufficiently sensitive to the changes in the electrical properties of the endothelial layer. It is concluded that the method presented here can be employed as non-invasive method for assessing endothelial layer function.

}, keywords = {Biomedical Engineering, Biomedical Engineering: methods, Corneal, Corneal: abnormalities, Corneal: metabolism, Corneal: pathology, Electric Impedance, Electric Impedance: diagnostic use, Endothelium, Finite Element Analysis, Humans, Permeability, Reproducibility of Results, Sensitivity and Specificity}, issn = {1873-4030}, doi = {10.1016/j.medengphy.2010.07.016}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20832346}, author = {A Guimera and Antoni Ivorra and Gabriel, G and R Villa} }