Abnormal findings on diagnostic imaging of other specified body structures [R93.8] / Cerebral aneurysm, nonruptured [I67.1], Reason for Study: ^Reason: PLEASE DO THIN CUTS POSTERIOR FOSSA AND FIESTA, Outside CTA saw an aneurysmal lesion adjacent to the right PICA. Brain MRIThere is relatively well circumscribed lesion [7.4mm (AP) x 8.1mm (RL) x 7.7mm (CC)] at the cisternal space, just inferior to the right inferior cerebellar peduncle and slightly outer aspect of the right foramen Luschka. The lesion shows iso/low signal intensity on T1, low signal intensity on T2 and homogenous enhancement. There is no mass effects and there is no evidence that the lesion is connected to vascular structure. Constellation of these findings suggest extra axial benign lesions such as calcified and prominent choroid plexus, small meningioma at or around choroid plexus. Extra axial metastatic lesion is a very remote possibility. There is no evidence of acute ischemic or hemorrhagic lesion on this scan.There is no evidence of other abnormal enhancement.Underlying brain shows diffuse brain atrophy with corresponding prominent ventricle enlargement.There are subtle patchy high signal intensities on periventricular white matter indicating non specific small vessel ischemic disease.The paranasal sinuses and mastoid air cells are clear.Brain MRA:3D time of flight MOTSA MRA brain images with maximum intensity projections of the anterior/posterior intracranial circulation demonstrate normal ICAs, MCAs and ACAs. Vertebrobasilar system appears to be normal. Bilateral Pcom arteries and Acom artery are patent.There is no evidence of intracranial arterial aneurysm.No intracranial arterial luminal stenosis.
1. Extra axial enhancing lesion on the inferior aspect of the right inferior cerebellar peduncle as described above. Diagnostic possibilities include prominent calcified choroid plexus or associated small meningioma.2. No evidence of intracranial arterial aneurysm. No evidence of intracranial arterial luminal stenosis. 