Acute PCA territory infarct - medial branch

Non-contrast CT head study show hypodensity in the left splenium of the corpus callosum extending posteriorly into the left occipital lobe. There is a further region of hypodensity in the left posterolateral thalamus.

Focal periventricular hypodensities on figure C and D are old lacunar infarcts (comparison was made to previous study which is not shown and subsequent MRI DWI/ADC assessment does not demonstrate restricted diffusion)  

(1) MRA demonstrates absence of the left medial branch of PCA. 

(2) 3D reconstruction shows absence of left medial branch of PCA. 

(3) DWI and ADC (not shown) shows restricted diffusion of the left splenium of corpus callosum, the left medial occipital lobe. This confirms acute infarction of vascular territory supplied by the medial branch of of PCA.  In addition restricted diffusion in the left posterolateral thalamus suggest involvement of the left lateral posterior choroidal artery which may arise from either P2 or P3 segment of PCA.