OBJECTIVE: Pharmacotherapy for epilepsy is limited with 30% of patients refractory to this approach of suppressing seizures. Current surgical options are invasive and carry significant morbidities including infection, bleeding, and the potential for deleterious neurocognitive effects. As a result, there is a burgeoning need for innovation to develop safer and efficacious interventions. METHODS: Four distinct catheters (2 existing: Cardima catheter, Standard EPT Blazer catheter; 2 new prototypes: balloon catheter, basket catheters) were tested in 12 baboons (21-30 kg, 100% male). For each, we assessed whether or not the catheter was able to be maneuvered safely in various locations of the cerebral venous system, provide adequate cortical tissue contact to record signals, detect these signals as normal or abnormal, successfully stimulate the cortex, and capture the cortical tissue. Locations trialed included the petrosal sinus, straight sinus, vein of Galen, and occipital vein. Pacing cycle length and pacing thresholds varied among experiments. RESULTS: Successful mapping was conducted in all 12 baboons. The pacing cycle length varied from 75 ms to 650 ms depending on location of the cortex. Pacing threshold was recorded in 4/12 (33%) of the experiments; data is not available for the remaining 8/12 experiments. The threshold values ranged from 0.3 - 20 mAmps. Capture of cortical electrical activity was observed in 11/12 (91.7 %) experiments though the number of successful capture and stimulation attempts varied among experiments. The most reliable and consistent capture occurred with the use of our novel prototyped over-the-wire balloon catheter (9/12; 75%) and basket catheter (3/3; 100%). Necropsy and histology were performed post-experimentation, and only minimal complications were noted (Table 1). CONCLUSION: New electrode design can be maneuvered safely in the venous system, provide adequate cortical tissue contact to record signals, detect these signals as normal or abnormal, successfully stimulate the cortex, and capture cortical tissue. These novel devices merit further study in chronic baboons to establish long-term efficacy of continuous seizure recording.
OBJECTIVE: Pharmacotherapy for epilepsy is limited with 30% of patients refractory to this approach of suppressing seizures. Current surgical options are invasive and carry significant morbidities including infection, bleeding, and the potential for deleterious neurocognitive effects. As a result, there is a burgeoning need for innovation to develop safer and efficacious interventions. METHODS: Four distinct catheters (2 existing: Cardima catheter, Standard EPT Blazer catheter; 2 new prototypes: balloon catheter, basket catheters) were tested in 12 baboons (21-30 kg, 100% male). For each, we assessed whether or not the catheter was able to be maneuvered safely in various locations of the cerebral venous system, provide adequate cortical tissue contact to record signals, detect these signals as normal or abnormal, successfully stimulate the cortex, and capture the cortical tissue. Locations trialed included the petrosal sinus, straight sinus, vein of Galen, and occipital vein. Pacing cycle length and pacing thresholds varied among experiments. RESULTS: Successful mapping was conducted in all 12 baboons. The pacing cycle length varied from 75 ms to 650 ms depending on location of the cortex. Pacing threshold was recorded in 4/12 (33%) of the experiments; data is not available for the remaining 8/12 experiments. The threshold values ranged from 0.3 - 20 mAmps. Capture of cortical electrical activity was observed in 11/12 (91.7 %) experiments though the number of successful capture and stimulation attempts varied among experiments. The most reliable and consistent capture occurred with the use of our novel prototyped over-the-wire balloon catheter (9/12; 75%) and basket catheter (3/3; 100%). Necropsy and histology were performed post-experimentation, and only minimal complications were noted (Table 1). CONCLUSION: New electrode design can be maneuvered safely in the venous system, provide adequate cortical tissue contact to record signals, detect these signals as normal or abnormal, successfully stimulate the cortex, and capture cortical tissue. These novel devices merit further study in chronic baboons to establish long-term efficacy of continuous seizure recording.
Authors: Benhur D Henz; Paul A Friedman; Charles J Bruce; David R Holmes; Yasuo Okumura; Susan B Johnson; Douglas L Packer; Samuel J Asirvatham Journal: Epilepsy Res Date: 2008-06-06 Impact factor: 3.045
Authors: Tomas Kara; Pavel Leinveber; Michal Vlasin; Pavel Jurak; Miroslav Novak; Zdenek Novak; Jan Chrastina; Krzysztof Czechowicz; Milos Belehrad; Samuel J Asirvatham Journal: Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub Date: 2012-11-12 Impact factor: 1.245
Authors: Christopher V DeSIMONE; David R Holmes; Elisa Ebrille; Faisal F Syed; Dorothy J Ladewig; Susan B Mikell; Joanne Powers; Scott H Suddendorf; Emily J Gilles; Andrew J Danielsen; David O Hodge; Suraj Kapa; Samuel J Asirvatham Journal: J Cardiovasc Electrophysiol Date: 2015-08-16
Authors: Bernard Lim; Kalpathi L Venkatachalam; Arshad Jahangir; Susan B Johnson; Samuel J Asirvatham Journal: J Cardiovasc Electrophysiol Date: 2008-03-21
Authors: Benhur D Henz; Paul A Friedman; Charles J Bruce; David R Holmes; Mark Bower; Malini Madhavan; Christopher V DeSimone; Douglas Wahnschaffe; Steven Berhow; Andrew J Danielsen; Dorothy J Ladewig; Susan B Mikell; Susan B Johnson; Scott H Suddendorf; Tomas Kara; Gregory A Worrell; Samuel J Asirvatham Journal: Epilepsy Res Date: 2014-04-27 Impact factor: 3.045