Dolichoectasia of the basilar artery with increased diameter reaching 11 mm with intraluminal hyper & hypointense signal and a thin spiral intraluminal flap suggestive of basilar artery dissection. It is exerting mass effect upon the right side of the pons with encephalomalacic changes of the right side of the pons and midbrain.
High basilar tip location, indenting the floor of the third ventricle with no CSF flow obstruction or supratentorial ventricular dilatation.
Dominant right vertebral artery with tortuous course indenting the ventral aspect of the cervicomedullary junction, resulting in acute angulation of the junction posteriorly (seen on sagittal plane).