MRI
There is a left thalamic small area of diffusion restriction. It is likely to interrupt sensory tracts from the right hemi-body.
Time of flight MRA shows a large right vertebral artery, slender left. Left vertebral artery terminates as the PICA. This is still a normal variant. Basilar is flowing.
Both posterior cerebral arteries are flowing, both P1 segments are flowing. The area of infarction is conventionally supplied by small perforators from the left P1 segment basilar tip, left P2 segment. These segments are normal.
There is also supply from posterior communicators. The posterior communicators are present, reasonable calibre bilaterally.
Therefore likely occlusion of a very small branch vessel, not visible to MR. In the anterior circulation ICAs are flowing, M1 and A1 segments are flowing. Equal peripheral penetration of MCA and ACA branches.
CONCLUSION: Small left thalamic fresh infarct, which correlates very well with the symptoms.