Moyamoya disease [437.5], Reason for Study: ^Reason: hx moya moya, eval vasculature. Brain MRIThere is no evidence of acute ischemic or hemorrhagic lesion on the scan.Previously recognized right lateral medullary subtle high signal intensity on diffusion weighted image is not showing restricted diffusion on today's scan, therefore this lesion is likely represent artifacts.Diffuse volume loss with multifocal patch high signal intensity of white matter on the left hemisphere indicating chronic ischemic lesions, do not show any interval change since prior scan.Multiple tortuous small signal voids around suprasellar cistern especially left MCA M1 segment area as well as left side ambient cistern indicate Moyamoya vessels, no change since prior scan.Post enhancement scan shows prominent enhancement of bihemispheric cortical vessels most likely cortical veins. This finding may suggest relatively slow flow or increased blood volume.The ventricles, sulci and cisterns are symmetric and unremarkable. The midline structures and cranial-cervical junction are normal. Normal flow voids are identified in the major intracranial vessels. 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 non visualization of the left distal ICA and MCA but prominent left ACA. The distal right ICA and right MCA show luminal irregularity but the lumen size appear to be maintained. No significant interval change since prior scan.Perfusion MRIPerfusion MR scan using DSC technique shows mildly increased mean transit time on the left hemisphere especially frontal and posterior parietal lobes. The corresponding areas show slightly increased CBV and equivocal CBF.Please be reminded that the MR perfusion study can only provide relative value comparing to the other side which in this case is the right side.
1. No change of chronic ischemia related tissue loss on the left hemisphere, no change since prior scan.2. Moyamoya vessels on suprasellar cistern especially bilateral MCA M1 segment area and the left side ambient cistern.3. Occlusion of the left distal ICA and left MCA with prominent left ACA. Luminal irregularities were seen on the distal right ICA and right MCA with maintaining lumen size.4. Slightly increased MTT, increased CBV and equivocal CBF of the left hemisphere indicate possibly compensatory hypoperfusion status. 