Can a unilateral loss of otolithic function be clinically detected by assessment of the subjective visual vertical?
Brain Res Bull
; 40(5-6): 423-7; discussion 427-9, 1996.
Article
em En
| MEDLINE
| ID: mdl-8886369
ABSTRACT
Asymmetries in the settings of the subjective visual vertical after unilateral vestibular neurectomy during eccentric centrifugation [3] might provide a clinical test for unilateral otolithic function. This study investigates whether these asymmetries can also be revealed by a technically much easier practicable roll tilt of the subject relative to gravity instead of a roll tilt of the gravitational force on a human centrifuge. Twenty-seven normal subjects and 13 patients before surgery indicated verticality very accurately in the upright position. In 26 degrees roll positions (subjects seated on a slanted chair), they were only slightly more variable with no asymmetries larger than 5.3 and 7.8 degrees in normals and preoperative patients, respectively, between the roll positions toward the healthy and toward the affected ear. One week after surgical unilateral vestibular deafferentation, there was a consistent shift (mean 11.9 degrees) of the subjective vertical toward the affected ear in all patients and in all body positions. When the settings in the two roll tilt positions were referred to the setting in upright position, the group means of the patients were symmetrical although single subjects revealed asymmetries up to 22.4 degrees. Only one of four patients who were tested also during eccentric rotation revealed an important asymmetry with decreased sensitivity for tilts of the gravitational vector toward the affected ear. Measuring the subjective visual vertical assesses only asymmetrical tonic otolithic input, while a simple clinical test for unilateral otolithic sensitivity still has to be found.
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Bases de dados:
MEDLINE
Assunto principal:
Percepção Visual
/
Núcleos Vestibulares
/
Membrana dos Otólitos
/
Doença de Meniere
Limite:
Adolescent
/
Adult
/
Aged
/
Child
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Brain Res Bull
Ano de publicação:
1996
Tipo de documento:
Article
País de afiliação:
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