Fig 1. A and B, MR images showing the MR spectroscopy voxel placement. A, Midline sagittal T2-weighted MR image (TR/TE/NEX, 6790/103 ms/4) of a first-episode patient shows the ¹H-MR spectroscopic voxel placement. The maximal anteroposterior length (L) of the corpus callosum is identified (between points a’ and p’). The line drawn perpendicular to the a’p’ line at the anterior one-third point (point t) constitutes the posterior border of posterior genu region (separates the posterior genu from anterior midbody region). The horizontal line (line ac) drawn from the most anterior point of the corpus callosum (point a) to the "crook" of the genu (point c) separates the superior genu above and the inferior genu (open white arrow) below. The ¹H-MR spectroscopic voxel (black arrow) is placed into the superior and posterior genu of the corpus callosum. B, Coronal T1-weighted MR image (TR/TE/NEX, 530/30 ms/2) demonstrates the voxel placement into the genu of the corpus callosum.