The Bipolar Lithium Imaging Scan Study.

After obtaining written informed consent and within four weeks of reaching a stable therapeutic serum lithium concentration, lithium MR imaging will be performed using a 7 Tesla MR system (Achieva, Philips Medical Systems, Eindhoven, The Netherlands) with a dual-tuned 7Li/1H volume head coil (RAPID Biomedical GmbH, Rimpar, Germany). Various approaches, including whole-brain, voxel-wise, parcellation, mean, and regions of interest, will be applied to measure lithium concentrations.