Posterior circulation strokes affect key brain areas, causing dizziness and balance issues. They require specific treatment and rehab for recovery.
A posterior circulation stroke (PCS) occurs when blood flow is blocked in the arteries at the back of the brain. This type of stroke may affect important brain regions, such as the brainstem, cerebellum, and parts of the occipital and temporal lobes.
Since these areas of the brain control vital functions such as vision, balance, and coordination and basic life-support functions like breathing and heart rate, posterior circulation strokes can have serious consequences.
Early recognition and treatment of posterior circulation strokes are crucial to prevent severe complications or death.
Experts categorize posterior circulation strokes into a few main types, each affecting different arteries and brain regions.
These include:
- Basilar artery occlusion: This is a type of stroke where the basilar artery, which supplies blood to the brainstem and cerebellum, gets blocked. This blockage can lead to serious neurological issues.
Mortality rates exceed 85% but drop to around 40% with recanalization (restoration of blood flow). - Lateral medullary infarction (Wallenberg’s syndrome): This type of stroke occurs due to a blockage in the posterior inferior cerebellar artery or the vertebral artery, affecting the side of the medulla in the brain.
- Vertebral basilar syndrome: This occurs when there is a problem in the main arteries at the back of the brain, often due to head movement that blocks the vertebral artery.
How common are posterior circulation strokes?
Posterior circulation strokes make up about 20% of all strokes, affecting 70,000 to 100,000 people annually in the United States.
Posterior circulation strokes are generally caused by blockages or reduced blood flow in the arteries at the back of the brain.
Here are some of the specific causes of a PCS:
- Atherosclerosis: a buildup of fatty deposits on the arterial walls, leading to narrowed or blocked arteries
- Arterial occlusion: a blockage of blood flow in the arteries supplying the posterior circulation, such as the basilar artery or vertebral arteries
- Embolism: a blood clot or other debris that travels from another part of the body and blocks an artery in the posterior circulation
- Artery tear: a tear in the artery wall that can lead to blood flow obstruction, often caused by injury or occurring spontaneously in some cases
- Vasculitis: inflammation of the blood vessels that can cause narrowing or blockage in the arteries
- Cardiac sources: blood clots from the heart, such as those from atrial fibrillation, that travel to the posterior circulation arteries
- Fibromuscular dysplasia: a condition that causes abnormal cell growth in the arterial walls, leading to narrowing or aneurysm formation.
- Moyamoya disease: a rare condition involving progressive narrowing of the internal carotid arteries and their branches, leading to reduced blood flow to the brain
- Vascular malformations: abnormal connections between blood vessels, such as arteriovenous malformations or aneurysms, that can lead to bleeding or blockage
Symptoms of PCS can vary depending on which areas of the brain are affected, but they generally include:
- Vertigo: spinning sensation or dizziness, often with nausea
- Ataxia: difficulty with coordination and balance
- Headache: severe or sudden headaches
- Vomiting: nausea and vomiting, often with vertigo
- Vision changes: double vision, blurred vision, or partial loss of vision
- Cranial nerve abnormalities: issues with facial sensations or movements, like drooping or weakness
- Impaired consciousness: confusion or reduced alertness
- “Locked-in” syndrome: full consciousness with severe paralysis and an inability to move or speak
- Bilateral symptoms: weakness or sensory loss affecting both sides of the body
These symptoms can be challenging to diagnose because they overlap with other conditions and can vary greatly from person to person.
PCS treatment focuses on quickly restoring blood flow and minimizing brain damage. Initially, you would be given intravenous thrombolysis to dissolve clots or undergo mechanical thrombectomy to remove them.
Ongoing treatment would include medications like antiplatelets or anticoagulants to prevent further strokes and manage conditions like high blood pressure or diabetes.
Rehabilitation therapies, such as physical, occupational, and speech therapy, would help address symptoms and support recovery. In severe cases, surgery might be needed to manage complications like increased intracranial pressure.
What is the recovery time for a posterior circulation stroke
Recovery time for a PCS varies widely based on several factors, including the severity of the stroke, the specific areas of the brain affected, the treatment received, and the person’s overall health. Generally:
- Acute phase: Initial recovery occurs within the first few weeks to months, with improvements often noticeable during this period.
- Subacute phase: Progress continues over the next 6 to 12 months, as rehabilitation and therapy help people regain functions.
- Long-term recovery: Some people may see gradual improvements for up to 1 to 2 years, but recovery can slow down significantly after the first year.
While some individuals with PCS may experience significant recovery, others may face lasting disabilities or complications.
Some PCS cases have a low 30-day mortality rate of 3.6%. However, basilar artery occlusion can have a high mortality rate exceeding 80%.
A posterior circulation stroke occurs when there is a blockage in the arteries that supply blood to the back part of the brain. This can cause symptoms like dizziness, confusion, and coordination difficulties.
Quick treatment with anti-clotting drugs and rehab therapy is essential to restore blood flow, prevent more strokes, and support recovery. In severe cases, surgery may be needed to manage complications. Early diagnosis and prompt treatment are critical for better outcomes.