UMEM Educational Pearls

Category: Neurology

Title: Isolated Aphasia - Is It a Stroke?

Keywords: aphasia, stroke, middle cerebral artery, MCA, mimic, NIHSS (PubMed Search)

Posted: 11/8/2017 by WanTsu Wendy Chang, MD
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  • A retrospective single center study reviewed 788 patients who presented to the ED with concern of stroke and found 21 (3%) patients had only aphasia symptoms by the NIHSS.
  • None of these patients had evidence of infarct on neuroimaging.
  • 3 of these patients were diagnosed with possible transient ischemic attack (TIA) though also had other possible diagnoses.
  • Toxic/metabolic disturbances (39%), followed by seizure (11%), syncope (11%), and chronic medical problems (11%) were the most commonly diagnosed stroke mimics.

Take Home PointThis small but interesting study looked at the incidence of isolated aphasia presenting for concern of stroke. They found that none of their patients had evidence of an infarct, suggesting that strokes affecting language without motor or sensory deficits are uncommon.


  • Aphasia can be caused by ischemia of the left middle cerebral artery (MCA) territory.
  • However, a stroke of the left MCA territory is usually accompanied by some component of contralateral motor and sensory deficits, gaze deviation, or visual field cut.
  • Aphasia can also be caused by stroke mimics such as infection, toxic/metabolic abnormalities, dementia, migraine, or seizure.


Casella G, Llinas RH, Marsh EB. Isolated aphasia in the emergency department: The likelihood of ischemia is low. Clin Neurol Neurosurg 2017:163:24-26.

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