Presentation
Sudden onset of right-sided hemiparesis and dysarthria started 14 days ago.
Patient Data
An ill-defined cortical and subcortical lesion of altered signal measuring about
35 x 40 x 55 mm involving the left middle and inferior frontal gyrus displays areas of
water restriction on DWI images
The lesion displays high T1 and mixed-signal onT2/Flair sequences
In the post-contrast study, the lesion shows a gyral pattern of enhancement
There is no significant mass effect
Mild perilesional cerebral edematous changes
Brain MRS reveals mild reduction of NAA and marked elevation of lactate peaks
No significant rise of Cho peak.
Case Discussion
Regarding the sudden onset clinical findings and conventional MRI sequences, cerebral infarction in late subacute phase was the main differential diagnosis. MRS is more conclusive as there is marked elevation of lactate indicative of anerobic metabolism and mild reduction of NAA consistent with neuronal damage. The non rise of Cho peak excludes neoplastic activity.