Review Question - QID 202802

This patient is presenting with a loss of pain and temperature on ipsilateral face and contralateral body, vestibulocerebellar impairment, and Horner's syndrome which is consistent with lateral medullary ischemia.

Lateral medullary ischemia or Wallenberg syndrome is caused by an occlusion of the posterior inferior cerebellar artery (PICA) or one of its branches or of the vertebral artery. The area supplied by these vessels is, as the name implies, the lateral part of the medulla oblongata. Importantly, the most commonly affected artery is the vertebral artery, followed by the PICA, and superior middle and inferior medullary arteries.

Yew and Cheng discuss cerebrovascular accidents which can be classified into ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The classic presentation of an ischemic stroke is awakening with or the abrupt onset of focal neurologic deficits, the most common being difficulty with speech and weakness on one half of the body. A postictal seizure and hypoglycemia may mimic an ischemic stroke.

Day et al. review the lateral medullary syndrome, in which patients classically present with crossed hemisensory disturbance, ipsilateral Horner syndrome, and cerebellar signs. They note that there is variability in the presentation and often requires urgent neuroimaging for the diagnosis. They stress the importance of recognition of this condition as there is a key association between lateral medullary infarction and vertebral artery dissection.

Illustration A illustrates the region of infarct as well as the involved neural tracts shaded in grey.

Incorrect Answers:
Answer 1: Internal capsule strokes present with a pure motor or sensory defect.
Answer 2: A midbrain lesion classically involves CN III.
Answer 3: A pontine stroke results in the classic "locked-in" syndrome.
Answer 5: A cervical spinal cord lesion would not involve loss of sensation of the face.