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Clinical Pearl: How to Recognize a Bilateral Thalamic Stroke : Emergency Medicine News


Percheron’s artery, stroke


Percheron’s artery is a variant of the arterial supply to the thalamus in which a single artery supplies both sides of the thalamus and the midbrain. Occlusion of this artery can lead to a bilateral thalamic stroke.

Knowledge of the PDO and its occlusion is crucial for patient care and recovery. Patients exhibit unique characteristics such as excessive sleepiness and confusion during an infarction. (priest. 2021;13[11]:e19783;

PDO infarcts have four main acute characteristics: paralysis of vertical gaze (65%), memory impairment (58%), confusion (53%) and coma (42%). Three major difficulties are observed with this type of stroke:

  • Excessive drowsiness, leading to problems requiring a story. The coma-like presentation may delay diagnosis and limit post-stroke treatment.
  • The initial cranial CT scan shows no acute findings in most cases. This can mislead doctors to seek an alternative diagnosis for an altered mental state. Early therapeutic intervention is not considered accordingly.
  • Lack of familiarity with a PDO infarction and its clinical characteristics.

These barriers can have a significant negative impact on a patient’s prognosis. A Percheron infarction artery should also be retained in the differential diagnosis when elderly patients present with an altered mental state.

Consider follow-up imaging (MRI) when significant alteration in consciousness does not match initial imaging findings, especially when other subtle clinical signs are present (eg, paralysis of vertical gaze). (Neurol behavior. 2014;2014:154631;; Neurohospitalist. 2018;8[3]:141;

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