Table of Contents
Page created on June 3, 2021. Last updated on January 9, 2023 at 13:15
Introduction
With regards to stroke, it’s valuable to distinguish clinically whether the stroke affects the anterior or posterior circulation of the brain, and, if possible, which artery specifically. The anterior circulation of the brain consists of the internal carotid arteries, as well as the anterior and middle cerebral arteries. It supplies the majority of both cerebral hemispheres, except the occipital and medial temporal lobes.
The posterior circulation of the brain consists of the vertebral arteries, basilar artery, and posterior cerebral arteries. It supplies the brain stem, cerebellum, thalamus, and occipital cortex. Symptoms of the posterior circulation are covered in topic 26A.
The whole artery need not be affected, as smaller branches of the artery can be obstructed. As such, not all symptoms mentioned below must necessarily occur together. The most commonly affected vessel in ischaemic stroke is the middle cerebral artery.
Symptoms are generally acute and maximal at onset, but sometimes they progress gradually.
I don’t know why vertebral artery is included in the topic name, as it belongs to the posterior circulation and is also mentioned in the topic name of 26A.
The lecture does not separate symptoms according to artery, only according to anterior/posterior circulation, so it might be unnecessary to learn it artery-by-artery.
Symptoms of insufficient blood supply of the carotid artery territory
- Contralateral hemianopia
- Contralateral hemisensory loss
- Contralateral hemiparesis
- Aphasia
- Gaze palsy
- Contralateral facial palsy
- Contralateral pyramidal signs
The combination of hemiparesis, hemisensory loss, and hemianopia is sometimes called “hemi syndrome” in Hungarian literature.
Symptoms of insufficient blood supply of the anterior cerebral artery territory
- Contralateral lower extremity weakness
Symptoms of insufficient blood supply of the middle cerebral artery territory
- Contralateral upper extremity weakness
- Contralateral facial palsy
- Aphasia if in dominant hemisphere (usually left)
- Hemineglect if in nondominant hemisphere
basilar arteries indicate several, while there is only one basilar artery
Similarly, posterior cerebral artery indicate one, while there are two.