Please evaluate for cause of bleeding noted on MRI 2months ago: Double vision, bleeding noted on outside imaging in July, fatigue, gait unsteadiness. There is interval evolution of signal characteristics and size of a lesion within the posterior left midbrain that now displays intrinsically T1 and T2 hyperintensity with a complete rim of low susceptibility signal and measures up to 15 mm, previously 11 mm. There is effacement of the adjacent cerebral aqueduct, but the third and lateral ventricles are not particularly enlarged. There is no evidence of an associated developmental venous anomaly. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, paranasal sinuses, and scalp soft tissues are grossly unremarkable.
Interval increase in size and evolution of the appearance of a lesion within the posterior left midbrain may represent a cavernous malformation with subacute hemorrhage. 