Central compensation of deviated subjective visual vertical in Wallenberg's syndrome.

The central compensation of vestibular tonus imbalance due to
unilateral peripheral vestibular lesions has been repeatedly
documented. Little is known, however, about the central
compensation of vestibular tonus imbalance due to central lesions.
Dorsolateral medullary infarctions (Wallenberg’s syndrome)
typically cause a central vestibular tonus imbalance in the roll
plane with deviations of perceived verticality and ipsiversive body
lateropulsion. The course of normalisation of the tilts of
subjective visual vertical (SVV) in 50 patients who had acute
Wallenberg’s syndrome were retrospectively compared with that in 50
patients with acute vestibular neuritis. The initial displacement
of SVV was 9.8° in Wallenberg’s syndrome and 7° in vestibular
neuritis. The deviation of SVV significantly decreased over time
within days to weeks in both groups. This finding shows that the
time courses of the central compensation for dorsolateral medullary
infarctions and peripheral vestibular lesions are similar.