Vertigo and electronystagmography in uni- and bilateral Meniere's disease

In this study we performed standardized measurements of spontaneous nystagm us (SN), caloric tests and velocity step tests on a well-defined group of 9 2 Meniere patients as part of a diagnostic protocol. The aim of the study w as to look for results that could contribute to the diagnosis, but more spe cifically to a possible classification, of Meniere's disease. Relations wit h average hearing loss, shape of the audiogram, average hearing loss, durat ion and severity of perceived symptoms of disease and differences between u ni-and bilateral Meniere's disease were studied. Directional preponderance (DP) in unilaterally affected patients and labyrinthine preponderance (LP) in both uni- and bilaterally affected patients were significantly more ofte n directed towards the unaffected (uni) or least affected (bi) side (p = 0. 007, p = 0.001, p = 0.002, respectively). DP was correlated with LP (uni: R = 0.615, p < 0.001; bi: R = 0.438, p < 0.01), which means that the DP can be seen as a latent SN, directed to the unaffected side. With the caloric t est parameters LP and DP it was possible to find unilateral weakness. In un ilateral disease a duration of disease <2 years resulted in small asymmetry in time constant (T-asym), large LPs and LPs not only directed to the unaf fected, but also to the affected side, whereas a longer duration of disease gave large T-asym and small LPs that were only directed to the unaffected side. Patients suffered more severe vertigo in the first two years of the d isease. Studying the shape of the audiogram, it was found that patients hav ing an LP to the affected side, suggesting that this was a hyperactive laby rinth belonging to a beginning of the disease, never had a flat audiogram. In this study the LP was the best diagnostic parameter to find unilateral w eakness in patients with Meniere's disease. Together with the duration of t he disease, the severity of symptoms, the asymmetry in T and the shape of t he audiogram, it was possible to find two subgroups in the group of patient s with unilateral Meniere's disease. Vestibular data in association with ot her test results of the diagnostic protocol may contribute to a more sophis ticated classification of Meniere's disease. Copyright (C) 2001 S. Karger A G, Basel.