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 spinal artery column as well as the peripheral part of the anterior and central column. Disruption of blood supply to this particular artery in the medulla would result in a number of sensory deficits. If occlusion occurs above the level of sensory decussation, it would affect the proprioception, vibration, and two-point discrimination of the contralateral side of the body. When occurs below the level of sensory decussation, however, it would cause the effect on the ipsilateral side instead. Particularly at the upper cervical spinal cord where the posterior spinal artery supplies some parts of the ventral column, lesion might extend to the