Moyamoya disease [I67.5], Reason for Study: ^Reason: hx pial synangiosis: eval revascularization History: surveillance imaging Brain MRINo evidence of acute ischemic or hemorrhagic lesion on the scan.Focal encephalomalacia on the right basal ganglia and thalamus, hemosiderin deposition on the left mesial thalamus and right globus pallidus as well as encephalomalacia on the left inferior parietal lobule are again seen, unchanged since prior scan.Bilateral fronto-temporal craniectomy sites are redemonstrated, unchanged.The ventricles, sulci and cisterns are unremarkable. There is no mass, mass effect, edema, midline shift, intra or extra-axial fluid collection/hemorrhage, restricted diffusion/acute ischemia, or abnormal contrast enhancement. The midline structures and cranial-cervical junction are normal. The paranasal sinuses and mastoid air cells are clear.Brain MRA3D time of flight MOTSA MRA brain images with maximum intensity projections of the anterior/posterior intracranial circulation demonstrate obliteration of bilateral distal ICA supraclinoid segments which are consistent with known Moyamoya disease, unchanged since prior scan. Vertebrobasilar system appears to be normal. Reconstitution of bilateral MCAs and their branches are seen on source images, unchanged since prior scan.Vertebrobasilar system appears to be normal.Brain MR PerfusionAIF was measured from the distal basilar artery.The MTT appears to be delayed symmetrically on bilateral hemispheres comparing to posterior fossa.The rCBV and rCBF maps show approximately symmetric rCBV and rCBF but slightly decreased left hemispheric rCBV and rCBF.There is no focal significant increase or decreased area on either rCBV or rCBF maps. Above findings do not show any significant interval change since prior scan.
1. No evidence of acute ischemic or hemorrhagic lesion.2. No change of multifocal chronic ischemic and hemorrhagic lesions.3. No change of Moyamoya disease involving bilateral distal ICA with reconstitution of bilateral MCAs and their branches.4. No significant interval change of MR perfusion study. 