 Brain MRI:The ventricles and sulci are normal in size. The cerebellar tonsils are in normal position. There are no masses, mass effect or midline shift. The pituitary gland is normal in size. There is no evidence for intracranial hemorrhage or acute cerebral, brainstem or cerebellar infarction. No diffusion-weighted abnormalities are identified. There are no extraaxial fluid collections or subdural hematomas. The paranasal sinuses and mastoid air cells are clear. Brain MRA: There is antegrade flow within the distal bilateral vertebral arteries, within the basilar artery, distal bilateral internal carotid arteries and carotid siphons and bilateral anterior, middle and posterior cerebral arteries. No arterial stenoses, occlusions or aneurysms are identified. No arteriovenous malformations are identified and there is no evidence for cerebral vasculitis. Note is made of anatomic variation of a hypoplastic right vertebral artery which primarily ends in PICA as well as partial persistent right fetal PCA circulation.Neck MRA:There is conventional takeoff of the great vessels from the aortic arch without evidence for stenosis of the origin of the great vessels or of the bilateral vertebral arteries. There is poor visualization of the right vertebral artery throughout its entirety, and the left vertebral artery is large. The proximal 4 cm demonstrates a tiny lumen with a patent origin and uniformity of lumen caliber.There are no stenoses of the bilateral common, internal or external carotid arteries or of the bilateral carotid bifurcations. There is no evidence for vasculitis, fibromuscular dysplasia or dissection of the carotid or vertebral arterial systems within the neck. There are no vascular masses identified.
1.Negative MRI of the brain.2.Negative MRA of the brain.3.There is poor visualization of the right vertebral artery throughout its entirety, and the left vertebral artery is large. The proximal 4 cm demonstrates a tiny lumen with a patent origin and uniformity of lumen caliber. Given the brain MRA demonstrates what appears to be a hypoplastic distal right vertebral artery primarily ending in PICA, overall these findings most likely indicate congenital vertebral artery hypoplasia. However, since the right vertebral lumen is not visualized in its entirety, prior dissection cannot entirely be excluded. If deemed beneficial, a CTA of the neck could be obtained to evaluate for lumenal enhancement as well as the size of the transversarium foramen which can indicate congenital hypoplasia when small.