Lateral Medullary Syndrome (Wallenberg Syndrome)

Excerpt

Lateral medullary syndrome (LMS), also known as Wallenberg syndrome, is a neurological disorder affecting the dorsolateral medulla oblongata, most commonly caused by ischemic infarction of the posterior inferior cerebellar artery (PICA) or the vertebral artery (VA) (see Image. Lateral Medullary Syndrome). This condition was named after Adolf Wallenberg (1862–1949), a German neurologist and neuroanatomist who reported the first case of LMS. The LMS and resulting ischemic injury affect multiple neural structures in the posterolateral medulla, located posterior to the inferior olivary nucleus.

Affected structures include the inferior cerebellar peduncle, spinocerebellar tract, spinothalamic tract, descending sympathetic fibers, spinal trigeminal nucleus and tract, vestibular nuclei, and the nuclei and fibers of cranial nerves IX and X. Involvement of these structures results in a classic constellation of symptoms, including ipsilateral facial sensory loss, contralateral loss of pain and temperature sensation in the body, vertigo, ataxia, dysphagia, hoarseness, and Horner syndrome. Recent systematic reviews continue to underscore the clinical heterogeneity of LMS and emphasize the importance of early multimodal neuroimaging for diagnosis.