Cerebrovascular diseases can also present less commonly with headache or seizures. Any of these diseases can result in vascular dementia due to ischemic damage to the brain. Signs and symptoms
The most common presentation of cerebrovascular diseases is an acute stroke, which occurs when blood supply to the brain is compromised. Symptoms of stroke are usually rapid in onset, and may include weakness of one side of the face or body, numbness on one side of the face or body, inability to produce or understand speech, vision changes, and balance difficulties. Hemorrhagic strokes can present with a very severe, sudden headache associated with vomiting, neck stiffness, and decreased consciousness. Symptoms vary depending on the location and the size of the area of involvement of the stroke. Edema, or swelling, of the brain may occur which increases intracranial pressure and may result in brain herniation. A stroke may result in coma or death if it involves key areas of the brain.Other symptoms of cerebrovascular disease include migraines, seizures, epilepsy, or cognitive decline. However, cerebrovascular disease may go undetected for years until an acute stroke occurs. In addition, patients with some rare congenital cerebrovascular diseases may begin to have these symptoms in childhood. Causes
Congenital
Congenital diseases are medical conditions that are present at birth that may be associated with or inherited through genes. Examples of congenital cerebrovascular diseases include arteriovenous malformations, germinal matrix hemorrhage, and CADASIL (cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy). Arteriovenous malformations are abnormal tangles of blood vessels.
Dissections within the carotid arteries or vertebral arteries may compromise blood flow to the brain due to thrombosis, and dissections increase the risk of vessel rupture. Idiopathic
Idiopathic diseases are those that occur spontaneously without a known cause. Moyamoya is an example of an idiopathic cerebrovascular disorder that results in narrowing and occlusion of intracranial blood vessels. The most common presentation is stroke or transient ischemic attack, but cognitive decline within children may also be a presenting symptom. The disease may begin to show symptoms beginning in adolescence, but some may not have symptoms until adulthood. Pathophysiology
Mechanism of brain cell death
When a reduction in blood flow lasting seconds occurs, the brain tissue suffers ischemia, or inadequate blood supply. If the interruption of blood flow is not restored in minutes, the tissue suffers infarction followed by tissue death. When the low cerebral blood flow persists for a longer duration, this may develop into an infarction in the border zones (areas of poor blood flow between the major cerebral artery distributions). In more severe instances, global hypoxia-ischemia causes widespread brain injury leading to a severe cognitive sequelae called hypoxic-ischemic encephalopathy.An ischemic cascade occurs where an energetic molecular problem arises due to lack of oxygen and nutrients. The cascade results in decreased production of adenosine triphosphate (ATP), which is a high-energy molecule needed for cells in the brain to function. Consumption of ATP continues in spite of insufficient production, this causes total levels of ATP to decrease and lactate acidosis to become established (ionic homeostasis in neurons is lost).