Ensuring most optimal C3

Background: Finding the motor threshold over right hand area is an integral part of cortical mapping and conducted at approximately C3 on strip. Two different scalp-based techniques have been taught frequently to find position maximal stimulation. At Harvard, was found by measuring from 5 cm vertex a line tragus The second measurement based 10-20 International System where calculating 20% distance measured marking this value. Using both measurements ensured could be with least amount energy. Both 5-cm rule EEG system for TMS positioning were used C3. Method: 285 consecutive patients 14 clinics underwent using Harvard IS measures each patient. Physicians trained in how methods (20% tragus) .Physicians documented which method resulted strongest visual response Results: Eighty-five percent time, chosen as giving single pulse fifteen time used. percentage among ranged low 71% high 100%. Conclusions: No finding “C3” successful all time. ensures that lowest energy level will patient thus reducing discomfort patients. And, protocols being Generally, between these two 2.9 cm. This indicates if used, mother not found, recommended “hunt” buy moving coil one-centimeter block would missed target. Had dual technique available during FDA Child Adolescent Depression Study, one very few 12-year-old subjects data age group represented rather than subject excluded study due failure their threshold. Additionally, results stimulation provides physician more leeway reduce electromagnetic while maintaining treatment efficacy thus, potential painfulness increasing completing programs. Conflict Interest: None Funding: Disclosures: