Diagnosis: Arteriovenous malformation of cerebral vesselsClinical question: 3 t scanner please, s/p SRS for AVM 8/15/14 MRI of the brainNo diffusion weighted abnormalities are appreciated.The patient is status post left-sided craniotomy for removal of an arteriovenous malformation. Some signal changes at the surgical bed likely represent gliotic changesThere is a small tangle of flow voids present in the right perimesencephalic cistern and in the right geniculate nucleus. There is associated enhancement at the right geniculate nucleus which has decreased compared to the prior exam but is larger this focus of enhancement currently measures 13 x 6 mm axial dimensions. Than on the 11/17/2014 exam. On susceptibility there is new signal loss at the area of contrast enhancement.A punctate microhemorrhage is present in the left middle frontal gyrus. This is stable when compared to the prior examThe visualized portions of the paranasal sinuses demonstrate a small mucus retention cyst in the right maxillary sinus. The visualized portions of the mastoid air cells are clear. The visualized portions of the orbits are intact.MRA brain:Antegrade flow is present in the distal internal carotid arteries, the distal vertebral arteries, the basilar artery and the proximal anterior, middle and posterior cerebral arteries.There is a small tangle of vascular structures centered in the expected location of the right geniculate nucleus associated with mild enlargement of the the thalamogeniculate branches of the right posterior cerebral artery. These are less prominent than on the previous exams.The anterior communicating artery is medium-sized. The posterior communicating arteries are small. The vertebral arteries are similar in size.
1.Status post removal of left temporal lobe arteriovenous malformation with expected post treatment change.2.Findings suggest persistence of an arteriovenous malformation centered in the right geniculate nucleus. It appears to be slightly less prominent than on prior exams. Contrast enhancement possibly related to radiation treatment has regressed. There is susceptibility effect in this region likely relating to a reaction to the radiation treatment.