Lesion in lateral medulla; usually caused by vertebral artery thrombosis near posterior inferior cerebellar artery. Injuries occur in spinocerebellar tract (ipsilateral hemiplegia), CN V (ipsilateral loss of facial pain and temperature sensation), spinothalamic tract (contralateral loss of body pain and temperature sensation), vestibular nuclei (nystagmus), sympathetic tract (ipsilateral Horner syndrome), and nucleus ambiguus (dysphagia and dysphonia).