The clinical variability of Wallenberg's syndrome. The anatomical correlate of ipsilateral axial lateropulsion.

The dorso-lateral medullary syndrome (Wallenberg's syndrome) is produced by infarction of a wedge of lateral medulla posterior to the inferior olivary nucleus and is usually caused by vertebral artery occlusion. Ipsilateral axial lateropulsion as an initial symptom of vertebral artery occlusion is rather rare and the anatomical structure responsible is still uncertain. Here we describe two patients presenting with ipsilateral axial lateropulsion as an initial symptom of vertebral artery occlusion. In one the stroke affected the dorso-lateral aspect of the medulla, in the other more lateral aspects of the medulla were involved. Our data suggest that ipsilateral axial lateropulsion may be caused by lesions of different topography involving either the vestibular nuclei, the cerebellar peduncle or the spinocerebellar tracts.