From the Guidelines
Posterior circulation syndrome presents with symptoms such as binocular diplopia, dysarthria, dysphagia, ataxia, and other symptoms suggestive of posterior circulation stroke, which can lead to severe and debilitating consequences if not promptly addressed. These symptoms occur due to reduced blood flow to the back part of the brain, which supplies critical brain structures including the brainstem, cerebellum, and occipital lobes 1. The brainstem controls basic functions like breathing and consciousness, the cerebellum coordinates movement, and the occipital lobes process vision. When blood flow is compromised to these areas, characteristic symptoms emerge, including:
- Transient, fluctuating, or persistent unilateral weakness (face, arm, and/or leg)
- Transient, fluctuating, or persistent language/speech disturbance
- Fluctuating or persistent symptoms without motor weakness or language/speech disturbance (e.g., hemibody sensory symptoms, monocular vision loss, hemifield vision loss) 1. Other symptoms may include dizziness, vertigo, imbalance, and difficulty coordinating movements, as well as visual disturbances such as double vision, partial vision loss, or complete blindness, headaches, nausea, vomiting, slurred speech, difficulty swallowing, and weakness or numbness on one or both sides of the body 1. Immediate medical attention is crucial as posterior circulation syndrome can lead to serious complications including stroke and permanent neurological damage. Patients with posterior circulation involvement may have more severe clinical manifestations at presentation 1.
From the Research
Symptoms of Posterior Circulation Syndrome
The symptoms of posterior circulation syndrome can vary, but common symptoms include:
- Dizziness or vertigo, which can be more frequent before posterior circulation strokes 2
- Unilateral limb weakness (81.9%) 3
- Speech difficulty (46.3%) 3
- Unilateral limb numbness (31.0%) 3
- Ataxia (30.1%) 3
- Dysphagia (inability to swallow), which can be the predominant symptom in some cases 4
- Isolated vertigo, although this is rare (1.4%) 3
- Bulbar paralysis, unconsciousness, visual disorder, and amnesia, which can help to localize the lesions 3
Specific Symptoms and Signs
Specific symptoms and signs of posterior circulation ischemic stroke can include:
- Central facial or lingual palsy (61.1%) 3
- Dysarthria (46.3%) 3
- Unilateral limb sensory loss (31.0%) 3
- Crossed paralysis, although this is low (2.8%) 3
Diagnosis and Management
Diagnosing posterior circulation stroke can be challenging due to non-specific and fluctuating symptoms, but making the correct diagnosis is important as these strokes have a high chance of recurrence and can be life-threatening 5. Investigation and management largely follow those for stroke in general, although some specific differences exist, such as the preferred use of MRI for diagnosing posterior fossa lesions and the management of basilar artery thrombosis 6, 5.