Differential Diagnosis for Stroke Causing Dizziness

When considering a stroke that causes dizziness, it's crucial to approach the diagnosis systematically, considering the anatomy and physiology of the brain and its blood supply. The following differential diagnosis is organized into categories to help prioritize potential causes.

• Single Most Likely Diagnosis

  • Posterior Circulation Stroke (Vertebrobasilar Stroke): This is often the most likely diagnosis when dizziness is a prominent symptom. The vertebrobasilar system supplies blood to the brainstem, cerebellum, and parts of the temporal and occipital lobes. A stroke in this territory can cause dizziness due to involvement of the vestibular nuclei or their connections in the brainstem and cerebellum.

• Other Likely Diagnoses

  • Lateral Medullary Syndrome (Wallenberg's Syndrome): A specific type of posterior circulation stroke that affects the lateral part of the medulla oblongata. It can cause dizziness, along with other symptoms like difficulty swallowing, slurred speech, and numbness of the face.
  • Cerebellar Stroke: Strokes affecting the cerebellum can lead to dizziness, ataxia (loss of coordination), and nystagmus (abnormal eye movements). The cerebellum plays a key role in balance and coordination.

• Do Not Miss Diagnoses

  • Brainstem Stroke: While less common, strokes in the brainstem can be particularly dangerous due to the high concentration of vital functions controlled by this area, including breathing, heart rate, and blood pressure. Dizziness can be a symptom, along with more severe signs like coma or paralysis.
  • Vertebrobasilar Insufficiency: This condition involves transient symptoms due to decreased blood flow in the vertebrobasilar system, which can include dizziness. It's a warning sign for a potential stroke and requires immediate medical attention.

• Rare Diagnoses

  • CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy): A rare, inherited condition that affects the blood vessels in the brain, leading to subcortical strokes and leukoencephalopathy. Dizziness can be a symptom, but it's more commonly associated with migraine, psychiatric problems, and cognitive decline.
  • Moyamoya Disease: A rare condition caused by narrowing or blockage of the internal carotid artery and its branches, leading to reduced blood flow to the brain. It can cause strokes, and dizziness might be a symptom, although it's more commonly associated with other signs like hemiparesis or seizures.

Each of these diagnoses has a different set of accompanying symptoms and requires a thorough clinical evaluation, including imaging studies like MRI or CT scans, to confirm the diagnosis and guide treatment.