Accelerated Robotized Neuronavigated Continuous Theta Burst Stimulation (cTBS) in the treatment of Auditory Hallucinations in Schizophrenia - A Randomized Sham Controlled Trial

BACKGROUND: Auditory verbal hallucinations (AVH) are one of the core features of schizophrenia. In approximately 25% of patients with schizophrenia, AVH are refractory to psychotropic drug treatment and can chronically persist. Superior temporal cortex is implicated in AVH. Continuous Theta Burst Stimulation (cTBS) can be one of the add on treatment for auditory hallucination in refractory cases. Accelerated cTBS protocols have the advantage of shorter application time and lower stimulation intensity. In addition use of robotized neuronavigation will improve the accuracy of coil placement and thus localization of the stimulation site. AIM: We aimed to evaluate the efficacy of accelerated cTBS over left superior temporal cortex (STC) in improvement of AVH in schizophrenia, using neuronavigation and robotic arm. METHODS: 40 patients of schizophrenia with AVH, were enrolled for this randomized, sham controlled, double-blind trial. Each participant in the active group received cTBS comprising of 900 pulses (bursts of 3 stimuli at 50 Hz repeated at 5 Hz frequency), twice a day for 5 days per week for 3 consecutive weeks. AVH were assessed with PSYRATS(AHRS), PANSS & CGI. Assessments were carried out at baseline,1(st),3(rd) & 6(th) weeks. RESULTS: The improvement in AVH in active group at 1(st) 3(rd) & 6(th) week was not statistically significant at 0.05 (p-value) as compared to sham group. Stimulation was well tolerated. CONCLUSION: Results suggest that accelerated robotized neuronavigated cTBS does not appear to have substantial potential in the treatment of auditory hallucinations and further research should investigate individualised MRI guided neuronavigation with higher sample size.