VIDEO
(Doctor only)
Lacunar strokes
Lacunar strokes, also known as small-vessel disease or smallvessel occlusion, account for approximately 20–30% of strokes.
They are due to obstruction of penetrating end arteries off major intracranial arteries (off the MCA, basilar artery, PCA, ACA, and posterior communicating artery). These infarcts are <15mm diameter in size.
ARE AL L SMALL SUBCORTICAL STROKES <15 mmLACUNAR STROKES (i.e. DUE TO SMALL-VES SE L DISEASE)?
. No, they are not. 12% of small basal ganglia and 34% of centrum semiovale infarcts have a cardioembolic source, and 19% of small basal ganglia and 53% of centrum semiovale infarcts have large-artery occlusive disease.
. Some are larger than 15mm and are clearly not in a distribution of a single small arteriole.
. Not all lacunar syndromes (see below) are caused by small strokes.
. Therefore, even a ‘‘lacunar-looking’’ stroke, especially if it does not fit into a classic syndrome or appearance, warrants careful work-up for large-artery atherosclerosis and embolic source.
WHAT CAUSES LACUNAR STROKES?
. Lipohyalinosis is the classic pathology, but atherosclerosis is also a common cause for small-vessel occlusion.
. Seen from an epidemiological standpoint, hypertension is the only consistent risk factor, whereas contributions of diabetes mellitus, smoking, or hyperlipidemia are smaller, if any.
. Antihypertensive treatment is the only method that has been shown to reduce lacunar strokes in particular
LACUNAR SYNDROME S AND THEIR LOCALIZATION
. Pure motor hemiparesis (corona radiata, anterior or posterior limb of internal capsule, pons, and medullary pyramid).
. Pure sensory stroke (ventral posterior thalamus).
. Sensorimotor stroke (thalamus, corona radiata).
. Ataxic hemiparesis (not well localizing: pons, corona radiata, anterior or posterior limb of internal capsule, lentiform nucleus, cerebellum).
. Dysarthria – clumsy hand (anterior limb of internal capsule, genu, pons).
