Insular branches of middle cerebral artery (M2)
Arteriae insulares (M2)
The branches of the middle cerebral artery that run over the insula, deep in the lateral sulcus, forming its second (M2) segment.
At a glance
- English
- Insular branches of middle cerebral artery (M2)
- Latin (TA2)
- Arteriae insulares (M2)
- System
- Artery
- Region
- Head
- Side
- Paired, left and right
About the insular branches of middle cerebral artery (m2)
After its first part crosses the base of the brain, the middle cerebral artery turns sharply upwards at the limen insulae, the threshold of the insula. This bend is called the genu. Beyond it the artery, usually already divided into a superior and an inferior trunk, spreads over the surface of the insula as a group of vessels that make up its insular, or M2, part.
These vessels run upwards and backwards in the grooves between the short and long insular gyri, hidden under the frontal, parietal and temporal opercula. They reach the circular sulcus at the edge of the insula, where they turn outwards to begin the opercular segment. On the way they give many small arteries into the insular cortex. Most of these end in the insula itself, while some pass deeper to the extreme capsule and claustrum, and a few long ones reach the corona radiata.
On angiograms seen from the front, the looping vessels over the insula outline the lateral sulcus and help show whether a mass is pushing them out of place. An M2 blockage is a common cause of stroke and is increasingly treated by removing the clot through a catheter. Loss of supply to the insula often shows early on CT scans as loss of the normal contrast between grey and white matter there. Surgery for tumours of the insula has to preserve the long insular arteries to avoid damage to the deep motor pathways.
Course and supply
- Arises from
- Middle cerebral artery beyond its genu at the limen insulae, usually as its superior and inferior trunks.
- Ends in
- Reach the circular sulcus of the insula, where they continue as the opercular (M3) branches; small insular arteries end in the insular cortex and deeper.
- Supplies
- Supply the insular cortex, the extreme capsule and claustrum, and through long insular arteries part of the corona radiata.
Anthromica
See the insular branches of middle cerebral artery (m2) where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
