Lateral medullary syndrome, also known as Wallenberg syndrome, is a clinical syndrome caused by acute ischemia or infarction of the lateral medulla oblongata due to occlusion of the intracranial portion of the vertebral artery, PICA or its branches 1-3.
On this page:
Epidemiology
20% of ischemic strokes occur in the posterior circulation 5. Lateral medullary syndrome is the most prevalent posterior ischemic stroke syndrome 5.
Risk factors
Hypertension is the commonest risk factor followed by smoking and diabetes mellitus 5.
Clinical presentation
This syndrome is characterized by:
vestibulocerebellar symptoms: ipsilateral hemiataxia, vertigo, falling towards the side of lesion, multidirectional nystagmus (inferior cerebellar peduncle and vestibular nucleus) 1-3
autonomic dysfunction: ipsilateral Horner syndrome, hiccups 1-3
sensory symptoms: loss of pain and temperature over the ipsilateral face (this may be variable 8) and contralateral side of body 1-3
ipsilateral bulbar muscle weakness: hoarseness, dysphonia, dysphagia, and dysarthria, decreased gag reflex (nucleus ambiguus) 1-3
Pathology
Affected structures can include:
inferior cerebellar peduncle
dorsolateral medulla
descending spinal tract
nucleus of the trigeminal nerve
vagus nucleus and nerve
glossopharyngeal nucleus and nerve
descending sympathetic tract fibers
Etiology
Lateral medullary syndrome is most commonly caused by vertebral artery disease. Underlying pathology includes:
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
Radiographic features
MRI
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.
Unable to process the form. Check for errors and try again.