<unk>  is generally defined by the type of blood vessel affected (arterial or venous<unk>  and the precise location of the blood vessel or the organ supplied by it. Venous<unk>  Deep vein<unk>  Deep vein<unk>  (DVT) is the formation of a blood clot within a deep vein. It most commonly affects leg veins, such as the femoral vein. Three factors are important in the formation of a blood clot within a deep vein—these are the rate of blood flow, the thickness of the blood and qualities of the vessel wall. Classical signs of DVT include swelling, pain and redness of the affected area. Paget-Schroetter disease Paget-Schroetter disease or upper extremity DVT (UEDVT) is the obstruction of an arm vein (such as the axillary vein or subclavian vein) by a<unk> us. The condition usually comes to light after vigorous exercise and usually presents in younger, otherwise healthy people. Men are affected more than women. Budd-Chiari syndrome Budd-Chiari syndrome is the blockage of a hepatic vein or of the hepatic part of the inferior vena cava. This form of<unk>  presents with abdominal pain, ascites and enlarged liver. Treatment varies between therapy and surgical intervention by the use of shunts. Portal vein<unk>  Portal vein<unk>  affects the hepatic portal vein, which can lead to portal hypertension and reduction of the blood supply to the liver. It usually happens in the setting of another disease such as pancreatitis, cirrhosis, diverticulitis or cholangiocarcinoma. Renal vein<unk>  Renal vein<unk>  is the obstruction of the renal vein by a<unk> us. This tends to lead to reduced drainage from the kidney. Cerebral venous sinus<unk>  Cerebral venous sinus<unk>  (CVST) is a rare form of stroke which results from the blockage of the dural venous sinuses by a<unk> us. Symptoms may include headache, abnormal vision, any of the symptoms of stroke such as weakness of the face and limbs on one side of the body and seizures. The diagnosis is usually made with a CT or MRI scan. The majority of persons affected make a full recovery. The mortality rate is 4.3%. Jugular vein<unk>  Jugular vein<unk>  is a condition that may occur due to infection, intravenous drug use or malignancy. Jugular vein<unk>  can have a varying list of complications, including: systemic sepsis, pulmonary embolism, and papilledema. Though characterized by a sharp pain at the site of the vein, it can prove difficult to diagnose, because it can occur at random. Cavernous sinus<unk>  Cavernous sinus<unk>  is a specialised form of cerebral venous sinus<unk> , where there is<unk>  of the cavernous sinus of the basal skull dura, due to the retrograde spread of infection and endothelial damage from the danger triangle of the face. The facial veins in this area anastomose with the superior and inferior ophthalmic veins of the orbit, which drain directly posteriorly into the cavernous sinus through the superior orbital fissure. Staphyloccoal or Streptococcal infections of the face, for example nasal or upper lip pustules may thus spread directly into the cavernous sinus, causing stroke-like symptoms of double vision, squint, as well as spread of infection to cause meningitis. Arterial<unk>  Arterial<unk>  is the formation of a<unk> us within an artery. In most cases, arterial<unk>  follows rupture of atheroma (a fat-rich deposit in the blood vessel wall), and is therefore referred to as atherothrombosis. Arterial embolism occurs when clots then migrate downstream and can affect any organ. Alternatively, arterial occlusion occurs as a consequence of embolism of blood clots originating from the heart ("cardiogenic" emboli). The most common cause is atrial fibrillation, which causes a blood stasis within the atria with easy<unk> us formation, but blood clots can develop inside the heart for other reasons too as infective endocarditis. Stroke Acute<unk> us in the right MCA M1 branch A stroke is the rapid decline of brain function due to a disturbance in the supply of blood to the brain. This can be due to ischemia,<unk> us, embolus (a lodged particle) or hemorrhage (a bleed). In<unk> otic stroke, a<unk> us (blood clot) usually forms around atherosclerotic plaques. Since blockage of the artery is gradual, the onset of symptomatic<unk> otic strokes is slower.<unk> otic stroke can be divided into two categories—large vessel disease and small vessel disease. The former affects vessels such as the internal carotids, vertebral and the circle of Willis. The latter can affect smaller vessels such as the branches of the circle of Willis. Myocardial infarction Myocardial infarction (MI) or heart attack, is caused by ischemia, (restriction in the blood supply), often due to the obstruction of a coronary artery by a<unk> us. This restriction gives an insufficient supply of oxygen to the heart muscle which then results in tissue death (infarction). A lesion is then formed which is the infarct. MI can quickly become fatal if emergency medical treatment is not received promptly. If diagnosed within 12 hours of the initial episode (attack) then<unk> olytic therapy is initiated. Limb ischemia An arterial<unk> us or embolus can also form in the limbs, which can lead to acute limb ischemia. Other sites Hepatic artery<unk>  usually occurs as a devastating complication after liver transplantation.
Thrombosis
Thrombus
Angiopathy
Sclerosis 
Calcification
Infarction
Adhesion 
Abscess