The patient was admitted to the hospital, where he initially received a non-enhanced CT brain to evaluate his brain. Then subsequently received an MRI and MRA /MRV of the brain (normal MRA/MRV). 

Acute CT (obtained within an hour of symptom onset): Hyperattenuating lesion in the left lentiform nucleus mainly the putamen with surrounding hypodensity consistent with edema. minimal mass effect on the adjacent lateral ventricle and effacement of the nearby sulci is noted.

MRI obtained just after CT (within few hours after symptom onset): left putamen lesion with isointense of T1 and T2/FLAIR / bright signal intensity. Surrounding T2 bright signal consistent with edema. No significant enhancement (compare pre-and post-Gd images) suggestive of a hypertensive basal ganglia hemorrhage.

Hemorrhagic lesions in putamen – differential includes hypertensive hemorrhage, vascular malformation, and neoplasm. Hypertension is the presumed cause in 70-90% of cases.  2/3 hypertensive hemorrhages occur in the putamen. 

CT - hematoma appears as areas of high density with sharply defined borders - the mass effect and the surrounding extruded serum/edema are hypodense - the hematoma changes from high density to isodense and finally to hypodense relative to the brain density over time.