[The subjective visual vertical in vestibular disease].
OBJECTIVE
To assess and compare the accuracy to perceive visual verticality, with and without trunk-head tilt in the frontal plane (30 degrees), in patients with peripheral or central vestibular disease.


METHODS
Thirty eight patients accepted to participate, 23 with peripheral disease and 15 with central disease. We also evaluated 40 healthy subjects. Subjects were seated facing a screen with an anchored motorized bar (20 cm). They were asked to bring the line to vertical, using a joystick, 10 times while seated upright and 10 times while tilted 30 degrees to each side. An average of the distance from true vertical was calculated to determine the tilt of the visual vertical on each posture.


RESULTS
Always, estimations made by healthy subjects were < 2 degrees from true vertical. In patients, in upright posture the largest tilt of the visual vertical was observed in patients with peripheral disease and spontaneous nystagmus. However, in all patients the accuracy to estimate the true vertical decreased when they were evaluated with trunk-head tilt (p < 0.05). In this condition the sensitivity of the test increased from 34 to 85% and the efficacy from 68 to 93% (p < 0.05).


CONCLUSIONS
Trunk-head tilt in the frontal plane decreases the accuracy of patients with vestibular disease to visually perceive verticality. This finding shows that head-trunk tilt can improve the sensibility and efficacy of this test to assess the vestibular function.
Hospital Regional 72, Instituto Mexicano del Seguro Social.
Catalina
C
Aranda-Moreno
Kathrine
K
Jáuregui-Renaud
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015837:Vestibular Diseases / Q000503:physiopathology*; D014796:Visual Perception