Right orbitofrontal rTMS benefits patients with treatment-resistant depression after unsuccessful DLPFC rTMS

Abstract Repetitive transcranial magnetic stimulation (rTMS) is a clinically effective treatment in major depressive disorder (MDD) when targeting the dorsolateral prefrontal cortex (DLPFC). Yet, at least 44% of patients do not achieve remission, requiring validated alternatives, such as orbitofrontal (OFC) targeted rTMS. Preliminary results employing 1Hz OFC-rTMS show 30% achieving response (i.e. reduction ≥50% MDD symptoms) who were initially non-responsive to DMPFC-rTMS. In current study, we aimed replicate previously reported results, and identify variables that may predict outcome symptom patterns specific OFC-rTMS. Two groups (n1=25 n2=17), located Netherlands United States respectively, underwent after non-response DLPFC-rTMS. On average, group 1 received 42 DLPFC sessions, followed by 24 OFC sessions. 2, 21 sessions Collected data included age, sex, depression severity over course (BDI-II), medication use. The also sleep quality (PSQI, HSDQ), baseline anxiety stress (DASS), EEG individual alpha peak frequency (iAPF). Our both achieved 24% remission (BDI score≤12). 1, said was irrespective use or severity. Similar analyses 2 are ongoing. Further will be presented conference, clarifying whether priori defined outcome, an anhedonia cluster, dysphoric vs anxiosomatic clusters, derived iAPF. Moreover, explore effects on symptoms. consideration for non-responders Predictors enable future stratification, benefitting reducing number rTMS Research Category Technology Methods Clinical Research: 10. Transcranial Magnetic Stimulation (TMS) Keywords: TMS, OFC, DLPFC, Major