IDIOPATHIC DANDYS-SYNDROME

In 1941 Dandy described patients in whom he had performed bilateral ve stibular nerve sections who reported ''jumbling'' objects in their vis ual fields when in motion and difficulty walking in the dark. We use t he term Dandy's syndrome to describe patients with bilateral vestibula r loss as the cause of the above symptoms. The caloric response in the se patients is either markedly reduced or absent when the cause is in the peripheral vestibular system. This study explored whether differen ces exist between those patients in whom the cause is known and those patients with no known cause. We reviewed our experience with 105 pati ents in whom Dandy's syndrome was diagnosed between 1984 and 1994. Inf ormation on their presenting symptoms, findings on physical examinatio n, audiometric status, electronystagmographic findings, laboratory tes t results, symptom outcome, and cause was collected. Patients with kno wn causes (Meniere's disease, ototoxicity, tumors, vascular disease, t rauma, heredity, autoimmune disease, infection) were compared as a gro up with those with no known cause. Of the 105 patients 34 (32%) had no obvious cause for their symptoms despite an extensive evaluation. Thi s group was similar to those with a known cause except for having a gr eater preponderance of women (68% vs. 41%, p = 0.018) and an increased likelihood to have normal audiogram findings (53% vs. 19%, p = 0.0009 ). All other variables, including age, duration of and age at onset of symptoms, physical examination, and electronystagmographic findings d id not differ significantly between the two groups. Only 28% of patien ts with known causes and 40% (p < 0.05) of those with idiopathic Dandy 's syndrome had improvement of their symptoms, underscoring the proble m with rehabilitation, The results of this study are compared with ear lier reports from our and other institutions.