The anterior cerebral artery runs medially on the medial surface to the cerebral hemisphere, then around the corpus callosum as far as the parieto-occipital sulcus. This artery supplies the medial aspect of the anterior 3/5 of the cerebral hemisphere and the upper edge of the lateral surface.
It gives off the following Branches:
- Capsular branch
- Cortical branches
- Callosal branch
Cortical branches
- Frontal branch supplying the pre-frontal area.This is the area of mentality and inhibition of primitive reflexes
- Paracentral branch supplying the motor and sensory areas of the Lowerlimb, and the paracentral lobule (cortical bladder centre).
Callosal branch supplying the corpus callosum.
The ACA is divided into two segments:
The precommunal (A1) circle of Willis, or stem, which connects the internal carotid artery to the anterior communicating artery
The postcommunal (A2) segment distal to the anterior communicating artery
The A1 segment gives rise to several deep penetrating branches that supply
- The anterior limb of the internal capsule,
- The anterior perforate substance
- Amygdala
- Anterior hypothalamus
- The inferior part of the head of the caudate nucleus
Occlusion of a single A2 segment produce the contralateral symptoms
If both A2 segments arise from a single anterior cerebral stem (contralateral A1 segment atresia), the occlusion may affect both hemispheres.
Profound abulia (a delay in verbal and motor response)
Bilateral pyramidal signs with paraparesis or quadriparesis
Urinary incontinence result.
Blood supply of medial surface is done by branches of ACA
- Medial orbitofrontal artery
- Frontopolar artery.
- Callosomarginal artery.
- Medial prerolandic artery.
- Secondary motor area
- Pericallosal artery.
- Medial rolandic artery
- Post. parietal artery
- Splenial artery.
