Lateral Medullary Syndrome:
Lateral medullary syndrome (aka Wallenberg syndrome and posterior inferior cerebellar artery syndrome “PICA”) is a disease in which the patient has a constellation of neurologic symptoms due to injury to the lateral part of the medulla in the brain, resulting in tissue ischemia and necrosis.
This lecture on Lateral Medullary Syndrome has been provided by: 100lyric
Signs and Symptoms of Lateral Medullary Syndrome:
Lateral medullary syndrome is characterized by sensory deficits affecting the trunk (torso) and extremities on the opposite side of the infarction and sensory deficits affecting the face and cranial nerves on the same side with the infarct. Specifically, there is a loss of pain and temperature sensation on the contralateral (opposite) side of the body and ipsilateral (same) side of the face. This crossed finding is diagnostic for the syndrome.
Affected persons have difficulty in swallowing (dysphagia) resulting from involvement of the nucleus ambiguus, as well as slurred speech (dysarthria) and disordered vocal quality (dysphonia) . Damage to the spinal trigeminal nucleus causes absence of pain on the ipsilateral side of the face, as well as an absent corneal reflex.
The spinothalamic tract is damaged, resulting in loss of pain and temperature sensation to the opposite side of the body. The damage to the cerebellum or the inferior cerebellar peduncle can cause ataxia. Damage to the hypothalamospinal fibers disrupts sympathetic nervous system relay and gives symptoms analogous to Horner syndrome.
Nystagmus and vertigo, which may result in falling, caused from involvement of the region of Deiters’ nucleus and other vestibular nuclei. Onset is usually acute with severe vertigo.
Palatal myoclonus may be observed due to disruption of the central tegmental tract.
Features of Lateral Medullary Syndrome:
Cause of Lateral Medullary Syndrome:
It is the clinical manifestation resulting from occlusion of the posterior inferior cerebellar artery (PICA) or one of its branches or of the vertebral artery, in which the lateral part of the medulla oblongata infarcts, resulting in a typical pattern. The most commonly affected artery is the vertebral artery, followed by the PICA, superior middle and inferior medullary arteries.