MRI

On a T1-weighted MRI scan, look for atrophy in the ventromedial frontal cortex, bilateral posterior orbital frontal regions, bilateral insula, anterior cingulate cortex, dorsolateral frontal cortex and premotor cortex to support bvFTD.

SD patients often have severe bilateral, asymmetric anterior temporal atrophy (“knife edge atrophy”) as well as medial temporal atrophy. In SD the amygdala, temporal pole, fusiform and inferolateral temporal gyri are more severely atrophic than in typical AD. Unbiased measurements of T1-weighted MRI scans suggest that atrophy in SD is much more significant in temporal than extra-temporal brain regions.

MRI scans of PNFA patients show atrophy of the left frontal, insular, anterior parietal, perisylvian and superior temporal cortices.