Fronto-temporal lobar degeneration - agrammatic variant primary progressive aphasia

Significant encephalomalacia and volume loss is identified involving the left hemisphere. The atrophy affects the frontal lobe and temporal lobe more than the parietal and occipital lobe, however, all lobes are involved. 

At the inferior aspect of the left temporal lobe there is FLAIR hyperintensity in keeping with gliosis.

The hippocampal formation on the left is significantly atrophied but not to any further degree than the surrounding temporal lobe changes. The left sylvian fissure is widened.

Multiple focal regions of FLAIR hyperintensity are identified within the deep white matter bilaterally. These regions are more confluent in the region of the centrum semiovale bilaterally. These are most in keeping with moderate to severe small vessel ischemic changes.

Ventricular size remains age-appropriate. Note is made however of ex-vacuo dilatation of the left lateral ventricle adjacent to the regions of encephalomalacia. Midline structures demonstrate mild thinning of the corpus callosum without focal lesions identified.

Volume and signal within the basal ganglia and brainstem are preserved. No restricted diffusion to suggest acute ischemia.

RADIOPHARMACEUTICAL: 99mTc CERETEC 740 MBq 

RESULTS : Tracer uptake in the left cerebral cortex is notably decreased compared with the right. This is most severe in the left temporal lobe, extending into the parietal and posterior frontal cortex. The area of perfusion reduction corresponds with the areas of cortical atrophy evident on MRI.  Right cerebral cortical perfusion is normal. The basal ganglia retain normal perfusion. The left thalamus appears to be laterally displaced due to the ex vacuo dilatation of the left lateral ventricle, as is seen also on the MRI. 

OVERALL IMPRESSION: Left cortical perfusion reduction involving the temporal, parietal and posterior frontal cortices, and corresponding to cortical atrophy on the MRI.