Anterior Spinal Artery Syndrome: Ischemia or infarction of the spinal cord in the distribution of the anterior spinal artery, which supplies the ventral two-thirds of the spinal cord. This condition is usually associated with ATHEROSCLEROSIS of the aorta and may result from dissection of an AORTIC ANEURYSM or rarely dissection of the anterior spinal artery. Clinical features include weakness and loss of pain and temperature sensation below the level of injury, with relative sparing of position and vibratory sensation. (From Adams et al., Principles of Neurology, 6th ed, pp1249-50)Infarction: Formation of an infarct, which is NECROSIS in tissue due to local ISCHEMIA resulting from obstruction of BLOOD CIRCULATION, most commonly by a THROMBUS or EMBOLUS.Superior Mesenteric Artery Syndrome: DUODENAL OBSTRUCTION by the superior mesenteric artery (MESENTERIC ARTERY, SUPERIOR) which travels in the root of the MESENTERY and crosses over the DUODENUM. The syndrome is characterized by the dilated proximal duodenum and STOMACH, bloating, ABDOMINAL CRAMPS, and VOMITING. Often it is observed in patient with body casts after spinal surgery.Spinal Cord Vascular Diseases: Pathological processes involving any of the BLOOD VESSELS feeding the SPINAL CORD, such as the anterior and paired posterior spinal arteries or their many branches. Disease processes may include ATHEROSCLEROSIS; EMBOLISM; and ARTERIOVENOUS MALFORMATIONS leading to ISCHEMIA or HEMORRHAGE into the spinal cord (hematomyelia).Duodenostomy: Surgical formation of an opening into the DUODENUM.Vertebral Artery: The first branch of the SUBCLAVIAN ARTERY with distribution to muscles of the NECK; VERTEBRAE; SPINAL CORD; CEREBELLUM; and interior of the CEREBRUM.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Hypesthesia: Absent or reduced sensitivity to cutaneous stimulation.Arteries: The vessels carrying blood away from the heart.Angiography: Radiography of blood vessels after injection of a contrast medium.Paraplegia: Severe or complete loss of motor function in the lower extremities and lower portions of the trunk. This condition is most often associated with SPINAL CORD DISEASES, although BRAIN DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; and MUSCULAR DISEASES may also cause bilateral leg weakness.Duodenal Obstruction: Hindrance of the passage of luminal contents in the DUODENUM. Duodenal obstruction can be partial or complete, and caused by intrinsic or extrinsic factors. Simple obstruction is associated with diminished or stopped flow of luminal contents. Strangulating obstruction is associated with impaired blood flow to the duodenum in addition to obstructed flow of luminal contents.Jejunostomy: Surgical formation of an opening through the ABDOMINAL WALL into the JEJUNUM, usually for enteral hyperalimentation.Syndrome: A characteristic symptom complex.Enterostomy: Creation of an artificial external opening or fistula in the intestines.