Conclusion: Defective utricular function, reflected by deviation of the perceived visual horizontal or vertical, cannot by itself explain increased postural sway in the lateral direction for patients with unilateral vestibular deafferentation (uVD).
Objective: It is not known why some patients with chronic uVD report distressing unsteadiness while others do not. The objective of this study was to test the hypothesis that impaired utricular compensation, reflected by pathologic tilt in the subjective visual horizontal and vertical (SVH-V) test, would affect postural control in the lateral direction after uVD.
Patients and methods: The SVH-V was tested in 28 patients 6 months after translabyrinthine surgery for unilateral vestibular schwannoma, and correlated with posturography results.
Results: No increase in lateral and anterior-posterior sway, or the quotients between them, or for Romberg quotients, was found with increasing SVH-V tilt.