Differential Diagnosis for Stroke Location

To determine the location of a stroke, it's crucial to consider the clinical presentation, imaging findings, and the patient's medical history. The following differential diagnosis is organized into categories to help guide the diagnostic process:

• Single Most Likely Diagnosis
  • Middle Cerebral Artery (MCA) Stroke: This is often the most common location for ischemic strokes due to the large territory the MCA supplies, including parts of the frontal, parietal, and temporal lobes. Symptoms can include hemiparesis, hemisensory loss, and aphasia if the dominant hemisphere is affected.
• Other Likely Diagnoses
  • Anterior Cerebral Artery (ACA) Stroke: ACA strokes are less common but can result in significant deficits, including lower limb weakness, urinary incontinence, and cognitive changes. The ACA supplies the medial surfaces of the frontal and parietal lobes.
  • Posterior Cerebral Artery (PCA) Stroke: PCA strokes can lead to visual field defects, memory disturbances, and sometimes, cortical blindness. The PCA supplies the occipital lobe and parts of the temporal lobe.
  • Posterior Inferior Cerebellar Artery (PICA) or Vertebrobasilar Stroke: These strokes can present with vertigo, ataxia, dysarthria, and sometimes, crossed deficits (e.g., ipsilateral facial weakness and contralateral limb weakness). The vertebrobasilar system supplies the brainstem, cerebellum, and parts of the posterior inferior cerebrum.
• Do Not Miss Diagnoses
  • Brainstem Stroke: Although less common, brainstem strokes can be devastating due to the critical functions controlled by this area, including respiratory and cardiovascular regulation. Symptoms can be subtle or dramatic, including sudden loss of consciousness, cranial nerve palsies, and long tract signs.
  • Cerebellar Stroke: While often presenting with less dramatic symptoms than supratentorial strokes, cerebellar strokes can lead to significant ataxia, dysarthria, and, in rare cases, obstructive hydrocephalus due to cerebellar edema.
• Rare Diagnoses
  • Lacunar Stroke: These small vessel strokes can occur in deep structures, such as the basal ganglia, thalamus, or internal capsule, and present with pure motor or sensory strokes, ataxic hemiparesis, or dysarthria-clumsy hand syndrome, among other syndromes.
  • Border Zone Infarcts: These occur in areas between the territories of two major arteries and can present with a variety of symptoms depending on the location, including watershed infarcts between the ACA and MCA or between the MCA and PCA territories.

Each of these diagnoses requires careful consideration of the patient's clinical presentation, imaging studies (such as CT or MRI scans), and sometimes, additional diagnostic tests to accurately determine the location and type of stroke.