Lateral medullary syndrome
Citation, DOI & article data
Lateral medullary syndrome, also known as Wallenberg syndrome, is a clinical syndrome caused by an acute ischemic infarct of the lateral medulla oblongata. This is most commonly due to occlusion of the intracranial portion of the vertebral artery followed by PICA and its branches 1-3.
20% of ischemic strokes occur in the posterior circulation 5. Lateral medullary syndrome is the most prevalent posterior ischemic stroke syndrome 5.
This syndrome is characterized by:
- vestibulocerebellar symptoms: vertigo, falling towards the side of lesion, diplopia, and multidirectional nystagmus (inferior cerebellar peduncle and vestibular nucleus) 1-3
- autonomic dysfunction: ipsilateral Horner syndrome, hiccups 1-3
- sensory symptoms: initially abnormal stabbing pain over the ipsilateral face then loss of pain and temperature sensation over the contralateral side of body (spinal trigeminal nucleus involvement) 1-3
- ipsilateral bulbar muscle weakness: hoarseness, dysphonia, dysphagia, and dysarthria, decreased gag reflex (nucleus ambiguus) 1-3
Lateral medullary syndrome is caused most commonly by:
- atherothrombotic occlusion of the vertebral artery, the posterior inferior cerebellar artery, or the medullary arteries
- cerebral embolism
- vertebral artery dissection, the commonest cause in young patients
- hypoplastic vertebral artery 7
MRI with DWI is the best diagnostic test to confirm the infarct in the lateral medulla 6. The infarcted area has high DWI signal and is low signal on ADC 6.
History and etymology
The syndrome was first described by Adolf Wallenberg (1862-1949), a German physician, in 1895 4.
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- 2. Kim JS. Pure lateral medullary infarction: clinical-radiological correlation of 130 acute, consecutive patients. Brain. 2003;126 (8): 1864-72. doi:10.1093/brain/awg169 - Pubmed citation
- 3. Allan Ropper, Joshua Klein, Martin Samuels. Adams and Victor's Principles of Neurology 10th Edition. (2014) ISBN: 9780071794794
- 4. Wallenberg A. Acute bulbar affection. Arch Psychiatr Nervenheilkd. 1895;27:504-540.
- 5. Lui F, Tadi P, Anilkumar AC. Wallenberg Syndrome. (2019) Pubmed
- 6. Kitis O, Calli C, Yunten N, Kocaman A, Sirin H. Wallenberg's lateral medullary syndrome: diffusion‐weighted imaging findings:. (2016) Acta Radiologica. 87 (6): 40-44. doi:10.17116/terarkh201587640-44 - Pubmed
- 7. Fatima Saleem & Joe M Das. Lateral Medullary Syndrome. StatPearls Publishing. 2021. PMID 31869134