The frequency of vertigo attacks diminishes within 5-10 years. Hearing loss (of about 50-60 dB) and vestibular function decrement (of about 35-50%) take place mainly in the first 5-10 years of disease. Drop attacks may occur early or late in the course of the disease, and remission is spontaneous in cmost cases. Bilaterality of the condition increases with increasing duration of the disease (up to 35% within 10 years, up to 47% within 20 years).

The recurrence rate in patients with a mean follow-up of 10 years was 50%. Most recurrences (80%) were within the first year after treatment, irrespective of the liberatory maneuver applied. None of the patients observed a recurrence after a symptom-free period of 8 years. Recurrences were seen significantly more often in women (58% versus 39%). The recurrence rate of patients in the seventh decade was half that of those in the sixth decade (p=0.0009). A history of three or more BPPV attacks prior to treatment indicated a higher risk of impending multiple recurrences in about two-thirds of the patients.

Among 4470 consecutive neurological impatients presenting “with typical neurological symptoms” 405 (9%) were found to have psychogenic rather than neurological dysfunction of the nervous system as the primary cause of admission. This probably represents a conservative figure, since secondary and minor pseudoneurological symptoms were not included. Retrospective analysis of these cases showed that pain was the most common psychogenic symptom, followed by motor symptoms (in particular stance and gait disturbances), dizziness, psychogenic seizures, sensory symptoms, and visual dysfunction. Unilateral motor and sensory symptoms were equally distributed to the left and right side of the body. Psychiatric abnormalities in these patients were heterogenous. Depressive syndromes were most common (38%), whereas hysterical features were less frequent than expected (9%). On discharge, improvement was significantly better for patients with recent onset of symptoms (2 weeks or less) than for those with longstanding disturbances. Short‐term outcome was best for motor symptoms and worst for pain. Improvement was independent of psychiatric findings, coexistence of a neurological disease, age, and sex.

Thirty-seven patients with psychogenic disorders of stance and gait were clinically evaluated, recorded on video, and analysed with regard to clinical phenomenology. Characteristic, suggestive and unspecific features were identified. Six characteristic features proved most valuable for diagnosis of psychogenesis, as they occurred alone or in combination in 97% of patients: (1) momentary fluctuations of stance and gait, often in response to suggestion; (2) excessive slowness or hesitation of locomotion incompatible with neurological disease; (3) "psychogenic" Romberg test with a build-up of sway amplitudes after a silent latency or with improvement by distraction; (4) uneconomic postures with wastage of muscular energy; (5) the "walking on ice" gait pattern, which is characterized by small cautious steps with fixed ankle joints; (6) sudden buckling of the knees, usually without falls. Seventy-three percent of patients had additional suggestive features. Classification into characteristic subtypes was not found useful because predominant features varied from patient to patient and occurred in various combinations. Factitious impairment of stance and gait was studied in 13 healthy drama students. Simulated gait dysfunction appeared less conspicuous and more difficult to diagnose than the clinical psychogenic disorders.

Bilateral vestibulopathy (BV) is characterized by impaired or lost function of both peripheral labyrinths or of the eighth nerves. In a review of 255 patients (mean age +/- SD, 62 +/- 16 years) with BV diagnosed in the authors' dizziness unit between 1988 and 2005, 62% of the patients were male. Previous vertigo attacks had occurred in 36%, indicating a sequential manifestation. The definite cause of BV was determined in 24% and the probable cause in 25%. The most common causes were ototoxic aminoglycosides (13%), Ménière's disease (7%), and meningitis (5%). Strikingly, 25% exhibited cerebellar signs. Cerebellar dysfunction was associated with peripheral polyneuropathy in 32% compared with 18% in BV patients without cerebellar signs. In a follow-up study on 82 BV-patients (mean age at the time of diagnosis 56.3 +/- 17.6 years), the frequency and degree of recovery or worsening of vestibular function over time were determined. The patients were reexamined 51 +/- 6 months after the first examination. Electronystagmography with bithermal caloric irrigation was analyzed by measurement of the mean peak slow-phase velocity (SPV) of the induced nystagmus. Statistical analysis of the mean peak SPV revealed a nonsignificant worsening over time (initial mean peak SPV 3.0 +/- 3.5 degrees/s vs. 2.1 +/- 2.8 degrees/s). Only patients with BV due to meningitis exhibited an increasing, but nonsignificant SPV (1.0 +/- 1.4 degrees/s vs. 1.9 +/- 1.6 degrees/s). Forty-three percent of patients subjectively rated the course of their disease as stable, 28% as worsened, and 29% as improved.