Lateral medullary syndrome

Lateral medullary syndrome is a neurological disorder causing a range of symptoms due to ischemia in the lateral part of the medulla oblongata in the brainstem. The ischemia is a result of a blockage most commonly in the vertebral artery or the posterior inferior cerebellar artery. Lateral medullary syndrome is also called Wallenberg's syndrome, posterior inferior cerebellar artery (PICA) syndrome and vertebral artery syndrome. This syndrome is characterized by sensory deficits that affect the trunk and extremities contralaterally (opposite to the lesion), and sensory deficits of the face and cranial nerves ipsilaterally (same side as the lesion). Specifically a loss of pain and temperature sensation if the lateral spinothalamic tract is involved. The cross body finding is a highly suggestive symptom from which the diagnosis may be considered (however, this a symptom common to all brainstem pathology). Patients often have difficulty walking or maintaining balance (ataxia), or difference in temperature of an object based on which side of the body the object of varying temperature is touching. Some patients may walk with a slant or experience skew deviation and illusions of room tilt. The nystagmus is commonly associated with vertigo spells. These vertigo spells can result in falling, caused from the involvement of the region of Deiters' nucleus. Common symptoms with lateral medullary syndrome may include difficulty swallowing, or dysphagia. This can be caused by the involvement of the nucleus , as it supplies the vagus and glossopharyngeal nerves. Slurred speech (dysarthria), and disordered vocal quality (dysphonia) are also common. 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 that are similar to the symptoms caused by Horner's syndrome – such as miosis, anhidrosis and partial ptosis. Palatal myoclonus, the twitching of the muscles of the mouth, may be observed due to disruption of the central tegmental tract.