 Brain MRI:Cerebellar peduncles extend 3-4 mm below the level of the foramen magnum, maintaining a rounded morphology, most consistent with cerebellar ectopia and not Chiari malformation.The ventricles and sulci are normal in size. The cerebellar tonsils are in normal position. There are no masses, mass effect or midline shift. Note is again made of a partially empty sella. 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 a tiny fenestration of the basilar artery just past the vertebral artery confluence, of no clinical significance.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 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.Cerebellar peduncles extend 3-4 mm below the level of the foramen magnum, maintaining a rounded morphology, most consistent with cerebellar ectopia and not Chiari malformation.2.Note is again made of a partially up the sella.3.Otherwise negative MRI of the brain including gadolinium enhancement.4.Negative MRA of the brain.5.Negative MRA of the neck.