The partially digested food arriving from the stomach stimulates the duodenum to produce hormones. These hormones tell the pancreas to release digestive enzymes, and the gallbladder to release bile. Much of the food digestion takes place in the duodenum.
Vertebral artery dissection (abbreviated VAD, often vertebral dissection) is a dissection (a flap-like tear) of the inner lining of the vertebral artery, which is located in the neck and supplies blood to the brain.fter the tear, blood enters the arterial wall and forms a blood clot, thickening the artery wall and often impeding blood flow. The symptoms of vertebral artery dissection include head and neck pain and intermittent or permanent stroke symptoms such as difficulty speaking, impaired coordination and visual loss.
Background. Carotid artery dissection begins as a tear in one of the carotid arteries of the neck, which allows blood under arterial pressure to enter the wall of the artery and split its layers.he blood dissects along the artery to create an intramural hematoma that leads to a thrombus, which can narrow the carotid artery lumen and become a nidus for distal embolization (see the image below). Arterial dissection. (A) Tear and elevation of intima from wall of artery, resulting in luminal stenosis.