Abstract
Aims: This study was designed to evaluate the postural effects on nystagmus response, during caloric vestibular stimulation. Methods: 43 female patients with right thoracic idiopathic scoliosis (mean age =13.5, scoliotic curves:20û– 40û) and 31 non-scoliotic healthy subjects (mean age=13.1) entered the study. In all patients was performed an electronystagmographic study of labyrinthine function with caloric stimulation. We evaluated: the frequency, the amplitude, the slow phase velocity of nystagmus. The differences in labyrinthine sensitivity were evaluated with the use of unilateral weakness parameter, while differences in left- and right- beating nystagmus evaluated by estimating the directional preponderance parameter. Results: 19 patients from the study group (44.2%), revealed unilateral weakness of the left labyrinth, while 24 patients from the study group (55.8%) had normal caloric responses. On contrary, only one patient of the control group (3.2%) revealed unilateral weakness of the left labyrinth (> 20%). These differences were statistical signiþcant (p< 0.05, Chi-Square test).17 patients from the study group (39.5%) revealed directional preponderance of the right-beating nystagmus. All these patients had also left unilateral weakness. Conclusions: From the above results we can conclude that in 17 patients from the study group the right labyrinth was preponderant, while in other 2 patients there was signiþcant evidence for this. The results are discussed with special reference to aetiology in idiopathic scoliosis.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
