The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Charles Love - One of the best experts on this subject based on the ideXlab platform.
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Lead extraction by selective operation of a nanosecond-pulsed 355nm laser
Optical Interactions with Tissue and Cells XXVII, 2016Co-Authors: Amir Herzog, Stefan Bogdan, Michael Glikson, Amiel A. Ishaaya, Charles LoveAbstract:Lead extraction (LE) is necessary for patients who are suffering from a related infection, or in opening venous occlusions that prevent the insertion of additional lead. In severe cases of fibrous encapsulation of the lead within a vein, laser-based cardiac LE has become one of the foremost methods of removal. In cases where the laser radiation (typically at 308 nm wavelength) interacts with the vein wall rather than with the fibrotic lesion, severe injury and subsequent bleeding may occur. Selective tissue ablation was previously demonstrated by a laser operating in the UV regime; however, it requires the use of sensitizers (e.g.: tetracycline). In this study, we present a preliminary examination of efficacy and safety aspects in the use of a nanosecond-pulsed solid-state laser radiation, at 355 nm wavelength, guided in a catheter consisting of optical fibers, in LE. Specifically, we demonstrate a correlation between the tissue elasticity and the catheter advancement rate, in ex-vivo experiments. Our results indicate a selectivity property for specific parameters of the laser radiation and catheter design. The selectivity is attributed to differences in the mechanical properties of the fibrotic tissue and a normal vein wall, leading to a different photomechanical response of the tissue’s extracellular matrix. Furthermore, we performed successful in-vivo animal trials, providing a basic proof of concept for using the suggested scheme in LE. Selective operation using a 355 nm laser may reduce the risk of Blood Vessel Perforation as well as the incidence of major adverse events.
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Selective tissue ablation using laser radiation at 355 nm in lead extraction by a hybrid catheter; a preliminary report.
Lasers in surgery and medicine, 2015Co-Authors: Amir Herzog, Stefan Bogdan, Michael Glikson, Amiel A. Ishaaya, Charles LoveAbstract:Background Current lead extraction (LE) devices can harm the Blood Vessel endothelium, increasing the risk of Perforation. Objective Proof of concept for using a solid-state pulsed laser at 355 nm with a hybrid catheter in LE. Methods A hybrid catheter was used comprising optical fibers for the delivery of 355 nm laser pulses at 30 Hz and 6 J/cm2 combined with a blunt mechanical blade. Specific parameters were chosen to enable selectivity in ablation, thereby reducing the risk of Blood Vessel Perforation. The design exploits differences in the mechanical properties of the fibrotic tissue and the normal Blood Vessel. Ex vivo ablation was performed to evaluate a hybrid catheter operation on various tissues. Two ex/in vivo pig studies used a free-floating electrode to which three bovine tendon pieces were glued. Finally, two in vivo dog model studies were performed on specimens with 4-5-year-old pacing lead implants, followed by a histopathology study. Results Catheter penetration rate in the ex vivo experiments was 0.1 mm/seconds for bovine tendon, 0.025 mm/seconds for porcine superior vena cava and 0.033 mm/seconds for porcine aorta. In the ex/in vivo pig study, the three tissue blocks were successfully dissected. In the in vivo dog study, the two leads were successfully extracted. In all in vivo tests, hemodynamic stability was maintained. Gross histopathology did not reveal any injury. Conclusions Ablation using 355 nm laser pulses in combination with a mechanical blunt blade may potentially constitute a viable alternative for LE. Lasers Surg. Med. © 2015 Wiley Periodicals, Inc.
Franco Odicino - One of the best experts on this subject based on the ideXlab platform.
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Laparoscopic Access with Optical Gasless Trocar: A Single-center Experience of 7431 Procedures.
Journal of Minimally Invasive Gynecology, 2019Co-Authors: Giuseppe Ciravolo, Paolo Donarini, Fabio Rampinelli, Chiara Visenzi, Franco OdicinoAbstract:ABSTRACT Study Objective To analyze the complications experienced and describe laparoscopic surgery using a gasless optical trocar. Design A retrospective study. Setting A department of obstetrics and gynecology in a tertiary center in Italy. Patients Seven thousand four hundred thirty-one surgical procedures were performed. Interventions From the hospital database, data were evaluated regarding major complications of laparoscopy with the ENDOPATH XCEL Bladeless Trocar (Ethicon, Johnson & Johnson, Somerville, NJ) performed between 2000 and 2017 by different laparoscopic surgeons. Measurements and Main Results The mean age of the patients was 40.66 ± 12.06 years (range, 13–91 years). The mean body mass index was 22.12 ± 3.64 kg/m2 (range, 15.74–41.51 kg/m2). The overall complication rate was 0.31% (23/7431 cases). Major complications included stomach Perforation in 1 procedure (0.014%), ileal Perforation in 2 procedures (0.028%), and Blood Vessel Perforation in 1 procedure (0.014%). Twelve procedures were completed with initial access through the omentum and 2 through an ovarian cyst. In 5 procedures (0.067%), conversion to laparotomy was required because the optical trocar failed to reach the abdominal cavity. With regard to complications requiring further intervention (n = 9), the rate of complications was 0.12%. Conclusions The optical gasless trocar is a feasible laparoscopic entry technique. The complication rate is lower than those reported previously.
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Laparoscopic Access with Optical Gasless Trocar: A Single-center Experience of 7431 Procedures.
Journal of Minimally Invasive Gynecology, 2019Co-Authors: Giuseppe Ciravolo, Paolo Donarini, Fabio Rampinelli, Chiara Visenzi, Franco OdicinoAbstract:ABSTRACT Study Objective To analyze the complications experienced and describe laparoscopic surgery using a gasless optical trocar. Design A retrospective study. Setting A department of obstetrics and gynecology in a tertiary center in Italy. Patients Seven thousand four hundred thirty-one surgical procedures were performed. Interventions From the hospital database, data were evaluated regarding major complications of laparoscopy with the ENDOPATH XCEL Bladeless Trocar (Ethicon, Johnson & Johnson, Somerville, NJ) performed between 2000 and 2017 by different laparoscopic surgeons. Measurements and Main Results The mean age of the patients was 40.66 ± 12.06 years (range, 13–91 years). The mean body mass index was 22.12 ± 3.64 kg/m2 (range, 15.74–41.51 kg/m2). The overall complication rate was 0.31% (23/7431 cases). Major complications included stomach Perforation in 1 procedure (0.014%), ileal Perforation in 2 procedures (0.028%), and Blood Vessel Perforation in 1 procedure (0.014%). Twelve procedures were completed with initial access through the omentum and 2 through an ovarian cyst. In 5 procedures (0.067%), conversion to laparotomy was required because the optical trocar failed to reach the abdominal cavity. With regard to complications requiring further intervention (n = 9), the rate of complications was 0.12%. Conclusions The optical gasless trocar is a feasible laparoscopic entry technique. The complication rate is lower than those reported previously.
Amir Herzog - One of the best experts on this subject based on the ideXlab platform.
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Lead extraction by selective operation of a nanosecond-pulsed 355nm laser
Optical Interactions with Tissue and Cells XXVII, 2016Co-Authors: Amir Herzog, Stefan Bogdan, Michael Glikson, Amiel A. Ishaaya, Charles LoveAbstract:Lead extraction (LE) is necessary for patients who are suffering from a related infection, or in opening venous occlusions that prevent the insertion of additional lead. In severe cases of fibrous encapsulation of the lead within a vein, laser-based cardiac LE has become one of the foremost methods of removal. In cases where the laser radiation (typically at 308 nm wavelength) interacts with the vein wall rather than with the fibrotic lesion, severe injury and subsequent bleeding may occur. Selective tissue ablation was previously demonstrated by a laser operating in the UV regime; however, it requires the use of sensitizers (e.g.: tetracycline). In this study, we present a preliminary examination of efficacy and safety aspects in the use of a nanosecond-pulsed solid-state laser radiation, at 355 nm wavelength, guided in a catheter consisting of optical fibers, in LE. Specifically, we demonstrate a correlation between the tissue elasticity and the catheter advancement rate, in ex-vivo experiments. Our results indicate a selectivity property for specific parameters of the laser radiation and catheter design. The selectivity is attributed to differences in the mechanical properties of the fibrotic tissue and a normal vein wall, leading to a different photomechanical response of the tissue’s extracellular matrix. Furthermore, we performed successful in-vivo animal trials, providing a basic proof of concept for using the suggested scheme in LE. Selective operation using a 355 nm laser may reduce the risk of Blood Vessel Perforation as well as the incidence of major adverse events.
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Selective tissue ablation using laser radiation at 355 nm in lead extraction by a hybrid catheter; a preliminary report.
Lasers in surgery and medicine, 2015Co-Authors: Amir Herzog, Stefan Bogdan, Michael Glikson, Amiel A. Ishaaya, Charles LoveAbstract:Background Current lead extraction (LE) devices can harm the Blood Vessel endothelium, increasing the risk of Perforation. Objective Proof of concept for using a solid-state pulsed laser at 355 nm with a hybrid catheter in LE. Methods A hybrid catheter was used comprising optical fibers for the delivery of 355 nm laser pulses at 30 Hz and 6 J/cm2 combined with a blunt mechanical blade. Specific parameters were chosen to enable selectivity in ablation, thereby reducing the risk of Blood Vessel Perforation. The design exploits differences in the mechanical properties of the fibrotic tissue and the normal Blood Vessel. Ex vivo ablation was performed to evaluate a hybrid catheter operation on various tissues. Two ex/in vivo pig studies used a free-floating electrode to which three bovine tendon pieces were glued. Finally, two in vivo dog model studies were performed on specimens with 4-5-year-old pacing lead implants, followed by a histopathology study. Results Catheter penetration rate in the ex vivo experiments was 0.1 mm/seconds for bovine tendon, 0.025 mm/seconds for porcine superior vena cava and 0.033 mm/seconds for porcine aorta. In the ex/in vivo pig study, the three tissue blocks were successfully dissected. In the in vivo dog study, the two leads were successfully extracted. In all in vivo tests, hemodynamic stability was maintained. Gross histopathology did not reveal any injury. Conclusions Ablation using 355 nm laser pulses in combination with a mechanical blunt blade may potentially constitute a viable alternative for LE. Lasers Surg. Med. © 2015 Wiley Periodicals, Inc.
Herbert Stepp - One of the best experts on this subject based on the ideXlab platform.
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ICG-assisted Blood Vessel detection during stereotactic neurosurgery: Simulation study on excitation power limitations due to thermal effects in human brain tissue
Photodiagnosis and photodynamic therapy, 2014Co-Authors: Adrian Rühm, Ronald Sroka, Werner Göbel, Herbert SteppAbstract:Summary Background Intraoperative Blood Vessel detection based on intraluminal indocyanin-green (ICG) would allow to minimize the risk of Blood Vessel Perforation during stereotactic brain tumor biopsy. For a fiber-based approach compatible with clinical conditions, the maximum tolerable excitation light power was derived from simulations of the thermal heat load on the tissue. Methods Using the simulation software LITCIT, the temperature distribution in human brain tissue was calculated as a function of time for realistic single-fiber probes (0.72 mm active diameter, numerical aperture 0.35, optional focusing to 0.29 mm diameter) and for the optimum ICG excitation wavelength of 785 nm. The asymptotic maximum temperature in the simulated tissue region was derived for different radiant fluxes at the distal fiber end. Worst case values were assumed for all other parameters. In addition to homogeneous (normal and tumor) brain tissue with homogeneous Blood perfusion, models with localized extra Blood Vessels incorporated ahead of the distal fiber end were investigated. Results If one demands that destruction of normal brain tissue must be excluded by limiting the tissue heating to 42 °C, then the radiant flux at the distal fiber end must be limited to 33 mW with and 43 mW without focusing. When considering extra Blood Vessels of 0.1 mm diameter incorporated into homogeneously perfused brain tissue, the tolerable radiant flux is reduced to 22 mW with and 32 mW without focusing. The threshold value according to legal laser safety regulations for human skin tissue is 28.5 mW. Conclusions For the envisaged modality of Blood Vessel detection, light power limits for an application-relevant fiber configuration were determined and found to be roughly consistent with present legal regulations for skin tissue.
Giuseppe Ciravolo - One of the best experts on this subject based on the ideXlab platform.
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Laparoscopic Access with Optical Gasless Trocar: A Single-center Experience of 7431 Procedures.
Journal of Minimally Invasive Gynecology, 2019Co-Authors: Giuseppe Ciravolo, Paolo Donarini, Fabio Rampinelli, Chiara Visenzi, Franco OdicinoAbstract:ABSTRACT Study Objective To analyze the complications experienced and describe laparoscopic surgery using a gasless optical trocar. Design A retrospective study. Setting A department of obstetrics and gynecology in a tertiary center in Italy. Patients Seven thousand four hundred thirty-one surgical procedures were performed. Interventions From the hospital database, data were evaluated regarding major complications of laparoscopy with the ENDOPATH XCEL Bladeless Trocar (Ethicon, Johnson & Johnson, Somerville, NJ) performed between 2000 and 2017 by different laparoscopic surgeons. Measurements and Main Results The mean age of the patients was 40.66 ± 12.06 years (range, 13–91 years). The mean body mass index was 22.12 ± 3.64 kg/m2 (range, 15.74–41.51 kg/m2). The overall complication rate was 0.31% (23/7431 cases). Major complications included stomach Perforation in 1 procedure (0.014%), ileal Perforation in 2 procedures (0.028%), and Blood Vessel Perforation in 1 procedure (0.014%). Twelve procedures were completed with initial access through the omentum and 2 through an ovarian cyst. In 5 procedures (0.067%), conversion to laparotomy was required because the optical trocar failed to reach the abdominal cavity. With regard to complications requiring further intervention (n = 9), the rate of complications was 0.12%. Conclusions The optical gasless trocar is a feasible laparoscopic entry technique. The complication rate is lower than those reported previously.
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Laparoscopic Access with Optical Gasless Trocar: A Single-center Experience of 7431 Procedures.
Journal of Minimally Invasive Gynecology, 2019Co-Authors: Giuseppe Ciravolo, Paolo Donarini, Fabio Rampinelli, Chiara Visenzi, Franco OdicinoAbstract:ABSTRACT Study Objective To analyze the complications experienced and describe laparoscopic surgery using a gasless optical trocar. Design A retrospective study. Setting A department of obstetrics and gynecology in a tertiary center in Italy. Patients Seven thousand four hundred thirty-one surgical procedures were performed. Interventions From the hospital database, data were evaluated regarding major complications of laparoscopy with the ENDOPATH XCEL Bladeless Trocar (Ethicon, Johnson & Johnson, Somerville, NJ) performed between 2000 and 2017 by different laparoscopic surgeons. Measurements and Main Results The mean age of the patients was 40.66 ± 12.06 years (range, 13–91 years). The mean body mass index was 22.12 ± 3.64 kg/m2 (range, 15.74–41.51 kg/m2). The overall complication rate was 0.31% (23/7431 cases). Major complications included stomach Perforation in 1 procedure (0.014%), ileal Perforation in 2 procedures (0.028%), and Blood Vessel Perforation in 1 procedure (0.014%). Twelve procedures were completed with initial access through the omentum and 2 through an ovarian cyst. In 5 procedures (0.067%), conversion to laparotomy was required because the optical trocar failed to reach the abdominal cavity. With regard to complications requiring further intervention (n = 9), the rate of complications was 0.12%. Conclusions The optical gasless trocar is a feasible laparoscopic entry technique. The complication rate is lower than those reported previously.