Renal artery located above the renal vein. Supernumerary renal arteries (two or more arteries to a single kidney) are the most common renovascular anomaly, occurrence ranging from 25% to 40% of kidneys. Renal artery stenosis, or narrowing of one or both renal arteries will lead to hypertension as the affected kidneys release renin to increase blood pressure to preserve perfusion to the kidneys. RAS is typically diagnosed with duplex ultrasonography of the renal arteries. It is treated with the use of balloon angioplasty and stents, if necessary. Atherosclerosis can also affect the renal arteries and can lead to poor perfusion of the
Posterior inferior cerebellar artery medial branch continues backward to the notch between the two hemispheres of the cerebellum; while the lateral supplies the under surface of the cerebellum, as far as its lateral border, where it anastomoses with the anterior inferior cerebellar and the superior cerebellar branches of the basilar artery. Branches from this artery supply the choroid plexus of the fourth ventricle. A disrupted blood supply to this artery due to a blood clot or embolus will result in tissue damage and lead to lateral medullary syndrome, also known as posterior inferior cerebellar artery syndrome ("PICA syndrome"), or "Wallenberg syndrome." Severe occlusion of