@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 {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 {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 {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 {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 {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} } @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 {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 {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 {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 {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 {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} } @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 {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} } @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} } @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 {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} } @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} } @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 {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.} } @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} }