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Background Transcranial magnetic stimulation (TMS) is a rapidly expanding technology utilized in research and neuropsychiatric treatments. Yet, conventional TMS configurations affect primarily neurons that are aligned parallel to the induced electric field by a fixed coil, making the activation orientation-specific. A novel method termed rotational field TMS (rfTMS), where two orthogonal coils are operated with a 90° phase shift, produces rotation of the electric field vector over almost a complete cycle, and may stimulate larger portion of the neuronal population within a given brain area. Objective To compare the physiological effects of rfTMS and conventional unidirectional TMS (udTMS) in the motor cortex. Methods Hand and leg resting motor thresholds (rMT), and motor evoked potential (MEP) amplitudes and latencies (at 120% of rMT), were measured using a dual-coil array based on the H7-coil, in 8 healthy volunteers following stimulation at different orientations of either udTMS or rfTMS. Results For both target areas rfTMS produced significantly lower rMTs and much higher MEPs than those induced by udTMS, for comparable induced electric field amplitude. Both hand and leg rMTs were orientation-dependent. Conclusions rfTMS induces stronger physiologic effects in targeted brain regions at significantly lower intensities. Importantly, given the activation of a much larger population of neurons within a certain brain area, repeated application of rfTMS may induce different neuroplastic effects in neural networks, opening novel research and clinical opportunities.

Introduction Deep TMS with the H7 coil over the dmPFC/ACC was recently approved for the treatment of obsessive compulsive disorder (OCD) by the FDA based on a twenty-nine-treatment-six-week sham-controlled study. Objective Quantify the improvement patients and clinicians can expect from their initial six-weeks of treatment. Methods The current analysis (n = 68) combined data from two groups of patients: – patients from the multi-center study who received active dTMS (n = 42) – an open label sample (n = 26). All patients were assessed on a weekly basis with Yale Brown Obsessive Compulsive Scale (YBOCS). Results The YBOCS score decreased significantly by 8.6 ± 0.8 which represents a 30.1% reduction from baseline through week 6 of treatment (P Conclusions Six weeks of dTMS treatment for OCD resulted in both statistically and clinically significant improvement. Notably, in eight out of nine patients who were treated for more than twenty-nine treatments, their scores improved. Patients with higher baseline severity are less likely to achieve response within 6 weeks and may benefit from longer treatment. Similarly, responders may reach remission with extended treatment courses.

Background An acute course of dTMS typically involves treatments delivered 5 days a week, for 4 weeks. Should more treatments be given if the patient has not responded? Data are needed to inform decisions about the best next steps for acute non-responders. Objective To characterize response among acute-phase non-responders in a randomized controlled trial of deep repetitive transcranial magnetic stimulation (dTMS) monotherapy for medication-resistant depression. Methods Summary statistics and Kaplan-Meier curves were used to characterize outcomes of 33 medication-free Brainsway™ dTMS non-responders to double blind but active treatment at the end of 4 weeks (20 sessions), who then continued double blind but active twice–weekly treatment for up to 12 additional weeks. Results 24 participants (72.7%) achieved responder status during at least one rating with dTMS continuation -- 20 (60.6%) within four weeks, with 13 (39.4%) consistently meeting response criteria for the duration of the study. 20 (63.6%) achieved remission status at some point during treatment continuation. Conclusions A significant proportion of acute course non-responders to dTMS treatment eventually respond with continued treatment. Continuing TMS treatment beyond the acute course for non-responders may result in eventual response in over half of these individuals.