Isolated axial lateropulsion with ipsilesional subjective visual vertical tilt in caudal lateral medullary infarction

The isolated body lateropulsion has been well recognized in caudal lateral medullary infarction and postulated to result from the involvement of ipsilateral dorsal spinocerebellar tract which is known to convey proprioception of trunk and legs. However, there has been no case accompanied by the tilt of the subjective visual vertical in caudal lateral medullary infarction. Recently, it has been suggested that a lesion in the ipsilateral graviceptive vestibulothalamic pathway can lead to alteration of subjective visual vertical without ocular tilt reaction in various brainstem lesions. Here we describe two cases of caudal lateral medullary infarction with ipsilesional body lateropulsion and subjective visual vertical tilt but without limb ataxia or ocular tilt reaction. It could be hypothesized that the ascending graviceptive information from the spinal cord may run adjacent to the dorsal spinocerebellar tract or perception of the visual vertical can be influenced by ascending spinal proprioception.