Anterolateral central arteries
The anterolateral central arteries are a group of small arteries arising from the anterior part of the circle of Willis and supply the basal ganglia. They arise at the commencement of the middle cerebral artery and are arranged in two sets:
- Internal striate: passes upward through the inner segments of the lentiform nucleus and supplies the lentiform nucleus, caudate nucleus, and internal capsule;
- External striate: ascends through the outer segment of the lentiform nucleus and supplies the caudate nucleus.
More modern texts divide the anterolateral central arteries into lateral and medial striate arteries. The lenticulostriate arteries originate from the initial segment of middle cerebral artery. They are small perforating arteries, which enter the underside of the brain substance to supply blood to part of the basal ganglia and posterior limb of the internal capsule. The lenticulostriate perforators are end arteries.
The name of these arteries is derived from some of the structures they supply, namely the lentiform nucleus and the striatum.
Blockage of the lenticulostriate arteries causes lacunar infarcts. These infarcts are most often due to hyaline arteriosclerosis secondary to hypertension. This can lead to contralateral paresis and/or sensory loss of the face and body.