[Neuro-ophthalmologic and posturographic studies of patients with idiopathic torticollis]

The pathophysiology of idiopathic spasmodic torticollis is still unknown. In addition to genetic and other factors, one of the possible causes under discussion is a disturbance of the vestibular system. In order to analyse vestibular influences we investigated 40 patients with idiopathic torticollis using electronystagmography, fundus photography, measurement of the subjective visual vertical and posturography. The results of the neuroophthalmological investigations and the measurement of the visual vertical were within the normal range. 53% of the patients examined showed a slight central vestibular preponderance in the electronystagmography, whereas 38% demonstrated a slight pathological monocular torsion in the fundus photography. Posturographically, there were some indications of a slightly decreased gain in visual contribution to the postural control process. None of the results could be correlated to the extent of torticollis in the individual case. We propose that these results do not confirm the hypothesis of primary vestibular lesion in the pathogenesis of torticollis. A possible explanation of the results described could be a common basic lesion which causes the torticollis on the one hand and also affects the central vestibular system on the other hand.