P276 Transcranial Direct Current Stimulation (tDCS) replaces Electroconvulsive Therapy (ECT) in a patient with corpus callosum agenesis and catatonic schizophrenia

Abstract

The 42-year-old male patient with known complete Corpus Callosum Agenesis (CCA) had shown severe catatonic symptoms since adolescence and been treated with weekly electroconvulsive therapy (ECT) for almost six years, because drug treatment was ineffective. ECT was discontinued after the patient experienced a third degree atrioventricular block and cognitive deterioration. After obtaining approval from the local ethics committee and informed consent from the patient and his relatives, tDCS was started with the following stimulation settings: Anode over the left dorsolateral prefrontal cortex (F3) and cathode over the right (F4); 2 mA for 2 × 20 min/day (90-min interval), 3x/week for two weeks, once to twice weekly thereafter with the same parameter settings. A weekly clinical assessment was conducted that included the Bush-Francis Catatonia Rating Scale (BCRS). Functional magnetic resonance imaging was performed before and after 70 and 140 tDCS sessions to assess resting-state functional connectivity, structural brain volumes (T1-MPRAGE, T2-FLAIR) and Diffusion Tensor Imaging (DTI). The patient overall received about 300 tDCS sessions. The patient showed fewer catatonic symptoms during tDCS treatment than during ECT treatment (BCRS scores: 20-27/69 during ECT, 4-12/69 during tDCS with one outlier of a BCRS score of 18 at the September 9, 2015). His speech fluency, and personal hygiene improved. Seed-based functional connectivity in the left insula and the frontal brain showed decreased variability in the fluctuation of the BOLD signal at measurement t2 and t3 compared to baseline. Frontal and left insulair connectivity increased after 140 tDCS sessions compared to baseline. Post 140 tDCS sessions structural connectivity measured by the means of DTI showed an increased number of white matter fiber tracts (streamlines) in many brain regions with a focus in frontal (e.g. insulair cortex) and temporal (e.g. Hippocampus area) brain regions. This was also shown in volumetric brain changes in these regions. In this patient with severe catatonia, prefrontal tDCS was more effective than maintenance of ECT,suggesting that tDCS may exert clinically significant effects on catatonia even in a case of altered anatomical connectivity caused by CCA. The alterations in structural and functional MRI suggest strong changes that may be due to the long-term treatment using prefrontal tDCS and/or the possible recreation from ECT treatments/anesthesia. Download : Download high-res image (200KB) Download : Download full-size image Download : Download high-res image (138KB) Download : Download full-size image