From the Guidelines
Anterior circulation stroke, also known as Anterior Cerebral Artery (ACA) stroke, typically presents with contralateral lower limb weakness, sensory deficits, and possibly urinary incontinence due to the involvement of the medial aspect of the frontal lobe.
Pathophysiology
The pathophysiology of an ACA stroke involves occlusion of the anterior cerebral artery, which supplies blood to the medial aspect of the frontal lobe, including the motor and sensory areas for the lower limbs 1.
- The ACA is responsible for supplying blood to the medial frontal lobe, which controls lower limb movement and sensation.
- Occlusion of the ACA can result in contralateral lower limb weakness, sensory deficits, and possibly urinary incontinence.
Clinical Presentation
The clinical presentation of an ACA stroke can vary depending on the location and extent of the occlusion 1.
- Contralateral lower limb weakness is a common presenting symptom, as the ACA supplies the motor areas for the lower limbs.
- Sensory deficits, such as numbness or tingling, can also occur in the contralateral lower limb.
- Urinary incontinence may be present due to the involvement of the medial frontal lobe, which controls bladder function.
- Brain swelling can occur in patients with ACA stroke, although the overall risk is estimated to be 10% to 20% 1.
- Early CT scan hypodensity and hyperdense MCA signs can predict neurological deterioration 1.
- Management of brain swelling should include restriction of free water, correction of factors that exacerbate swelling, and elevation of the head of the bed 1.
From the Research
Pathophysiology of Anterior Circulation Stroke
- Anterior circulation stroke, also known as Anterior Cerebral Artery (ACA) stroke, occurs when there is an interruption of blood flow to the anterior portion of the brain 2.
- The pathophysiology of anterior circulation stroke involves a complex interplay of factors, including atherosclerosis, artery-to-artery embolism, and branch occlusion 3.
- In anterior circulation, middle cerebral artery atherosclerosis frequently produces subcortical infarction by way of branch occlusion, resulting in clinical syndromes similar to lacunar syndromes 3.
Clinical Presentation of Anterior Circulation Stroke
- The clinical presentation of anterior circulation stroke can vary widely, depending on the specific vascular territory involved and the extent of the infarct 2.
- Common symptoms of anterior circulation stroke include hemisyndromes, dysarthria, and cognitive symptoms 4.
- Patients with anterior circulation stroke may also exhibit decreased consciousness, visual field defects, and vestibulo-cerebellar signs, although these symptoms are more commonly associated with posterior circulation stroke 4.
- The National Institutes of Health Stroke Scale (NIHSS) score is often higher in patients with anterior circulation stroke compared to those with posterior circulation stroke 4, 5.
Comparison with Posterior Circulation Stroke
- Anterior circulation stroke and posterior circulation stroke have distinct clinical and radiological features 4, 5.
- Patients with posterior circulation stroke tend to have lower NIHSS scores and are more likely to experience symptoms such as headache, vomiting, and decreased consciousness 4, 5.
- The outcome at 3 months is similar between anterior and posterior circulation stroke, although patients with posterior circulation stroke may have a better long-term outcome when controlling for important prognostic variables 5.