Lacunar Infarction: Understanding This Type of Stroke

Lacunar infarction, also known as lacunar stroke, is a type of ischemic stroke that occurs when small arteries deep within the brain become blocked. These arteries, known as penetrating or perforating arteries, are responsible for supplying blood to deeper brain structures, including the basal ganglia, thalamus, and internal capsule. Unlike larger arteries that branch across the brain's surface, these smaller vessels dive directly into the brain tissue to provide essential nutrients and oxygen.

What Causes Lacunar Infarction?

The primary cause of lacunar infarction is the blockage of these small penetrating arteries due to the buildup of plaque or thickening of the artery walls—a condition often linked to chronic hypertension. When blood flow is restricted, the brain tissue supplied by that artery begins to die, leading to what is known as a lacunar lesion. These lesions are typically small, ranging from 0.5 to 2 centimeters in diameter, although some can be larger if the affected artery has significant branching.

How Is Lacunar Infarction Detected?

Following the death of brain cells due to lack of oxygen, the damaged tissue is eventually cleared away by the body's immune system, leaving behind a small cavity filled with cerebrospinal fluid. This cavity can be easily identified using brain imaging techniques such as CT scans or MRI. Radiologists often refer to these areas as lacunar infarcts or areas of cerebral softening.

Key Characteristics of Lacunar Lesions

One of the unique features of lacunar infarction is that it often presents with specific neurological symptoms without causing significant swelling or bleeding in the brain. These strokes are considered "silent" in some cases, meaning they may not always produce obvious symptoms, yet they can still contribute to cognitive decline or increase the risk of future strokes if left untreated.

Why Early Diagnosis Matters

Because lacunar infarcts are associated with small vessel disease, they highlight underlying vascular issues that may lead to more severe strokes or dementia over time. Detecting and managing risk factors such as high blood pressure, diabetes, and high cholesterol is crucial in preventing further damage. Early diagnosis through MRI and prompt treatment can significantly reduce the likelihood of recurrent strokes and improve long-term outcomes.