A left thalamic lacunar infarct is a ischemic infarction that occurs when the left thalamus stops receiving blood from vital cerebral arteries, according to Neuropathology-web.org. Lacunar infarcts account for roughly 20 percent of all strokes and occur in deep-rooted parts of the brain, such as the thalamus or basal ganglia.
An infarct refers to bodily tissue that has become inert due to the blockage of nearby blood vessels, explains Neuropathology-web.org. Lacunar infarcts develop frequently within the brains of people afflicted with high blood pressure and diabetes. Such conditions correlate to vascular diseases such as atherosclerosis and small vessel disease, which are both known to be major causes of ischemic infarctions in general.