There are two types of vascular diseases which I haven’t previously discussed: hypertensive cerebrovascular disease and vasculitis. I’ll discuss each of them here.
Hypertensive Cerebrovascular Disease (HCDs)
Hypertensive cerebrovascular disease is defined by types of diseases of the brain caused by high blood pressure. These types of diseases have decreased in recent years due to more extensive testing and treatment done at lower blood pressure levels. However, these diseases have not disappeared entirely.
Within the brain, HCDs can lead to intracerebral haemorrhage, slit haemorrhages, lacunar infarcts and hypertensive encephalopathy (diseases within the brain tissue as a result of high blood pressure). Since I’ve discussed intracerebral haemorrhages previously, I’ll only refer to the final three conditions.
Due to hypertension (high blood pressure), rupturing of veins can occur. In cases where the level of haemorrhaging is small, the bleed eventually gets resorbed, leaving behind a brown discolouration as well as a slitlike cavity on the blood vessel.
Lacunar infarcts are mostly found within the deep grey matter in the thalamus and basal ganglia, the pons, the deep white matter and within the inner capsule and are usually less than 15mm wide. They can either cause significant levels of neurological damage or they can remain asymptomatic, depending on the location. These infarcts create cavities, with tissue loss and some scattered macrophages and damage to glial cells.
Acute Hypertensive Encephalopathy (AHE)
Acute hypertensive encephalopathy or AHE is defined as abnormal functioning within the cerebrum. Symptoms associated with this disorder include vomiting, headaches, confusion, convulsions, and occasionally the person may slip into a coma. Under the microscope, petechiae (red or purple spots) and death of blood vessels within the grey matter can be seen.
Vasculitis is defined as inflammation of the blood vessels. Within the brain, this condition is known as primary angitis of the CNS, and it involves inflammation of small to medium sized vessels both with the brain and within the subarachnoid space in the meninges. There are also some systemic diseases which can lead to vasculitis in the brain: one example is polyarteritis nodosa, which can exhibit inflammation of the blood vessels and infarcts throughout the brain. Under the microscope, inflammation can be seen, as well as giant cells that are multinucleated and may or may not have granuloma formation and vessel wall destruction.