The Common Symptoms of Cerebrovascular Stenosis

Cerebrovascular stenosis, or the narrowing of blood vessels in the brain, can present a range of symptoms depending on the severity and location of the blockage. In mild cases, individuals may not experience any noticeable symptoms at all. However, as the narrowing becomes more severe, particularly in older adults, signs of reduced cerebral blood flow may begin to appear.

General Symptoms of Severe Narrowing

Among the more common symptoms associated with significant cerebrovascular stenosis are dizziness and a feeling of pressure or tightness in the head. These sensations often indicate impaired blood flow to the brain. The specific symptoms can vary greatly depending on which artery is affected and the extent of the narrowing.

Symptoms Based on Location of the Stenosis

Middle Cerebral Artery Stenosis

When the narrowing occurs in the middle cerebral artery, it can lead to reduced blood supply to the corresponding regions of the brain. This can result in contralateral hemiparesis or hemiplegia—weakness or paralysis on one side of the body—as well as sensory deficits. In more severe cases, vision disturbances such as hemianopia, or loss of half the visual field, may occur.

Vertebrobasilar Artery Stenosis

Narrowing in the vertebrobasilar system can lead to ischemia in the brainstem and cerebellum. This often causes symptoms such as dizziness, vertigo, nausea, vomiting, unsteady gait, and reduced muscle tone. If the stenosis occurs in the upper part of the basilar artery, it can affect consciousness and potentially lead to quadriplegia. The severity of symptoms generally correlates with the degree of narrowing and the area of the brain affected.

Understanding Asymptomatic Cases

Interestingly, some patients with completely occluded arteries may not exhibit any symptoms. This phenomenon is often due to the presence of a well-developed collateral circulation. In these cases, smaller blood vessels compensate by rerouting blood flow around the blockage, providing adequate nourishment to the affected brain tissue. The presence and effectiveness of these alternate pathways can vary significantly from person to person, which is why symptoms may differ even among individuals with similar levels of vascular narrowing.