Restricted dissociated sensory loss in a patient with a lateral medullary syndrome - A clinical-MRI study

Background-Various sensory syndromes in lateral medullary infarctions are d escribed. A small variation in the location of a lesion may lead to very di fferent clinical features, owing to the complex anatomy of the medulla oblo ngata. MRT may identify the location and extent of the ischemic lesions, al lowing a clear clinical-anatomical correlation. Case Description-We describe a man with an ischemic lesion in the right por tion of the lower medulla that presented a contralateral impairment of spin othalamic sensory modalities and an ipsilateral impairment of lemniscal mod alities with a restricted distribution (left forearm and hand, right hand a nd fingers, respectively). The restricted and dissociated sensory abnormali ties represent the only permanent neurological consequence of that lesion. Conclusions-The atypical sensory syndrome may be explained by the involveme nt of the medial portion of spinothalamic tract and the lateral portion of archiform fibers at the level of the lemniscal decussation.