Glucose and insulin profiles and their correlations in Ménière's disease.

Changes in carbohydrate metabolism, admittedly one of the most prevalent etiologies of Méière's syndrome, can be diagnosed early by 5-hour glucose and insulin curves with a 100-g glucose load, a test more sensitive than those traditionally used in investigating impaired glucose tolerance or diabetes mellitus. This study investigated carbohydrate metabolism characteristics in 64 patients with typical Ménière's disease. We demonstrated that 72% of them had some variable degree of hyperinsulinemia as shown by their plasma insulin curves, whereas alterations on the glucose curve (reactive hypoglycemia or hyperglycemia) were found for only 21%. More advanced hyperinsulinemic conditions (i.e., glucose intolerance or diabetes mellitus) were usually associated with changes in lipid profiles and with a central pattern of fat distribution and systemic hypertension. We found a very strong correlation between insulin concentrations measured by chemoluminescence and by radioimmunoassay; the latter, however, showed values 1.3 times higher than those measured by chemoluminescence. These findings confirm the need to include 5-hour glucose and insulin curves in the diagnostic routine when investigating Ménière's disease. In that way, an early diagnosis of hyperinsulinemia, the metabolic change most often involved in the pathogenesis of cochleovestibular disorders, can be made.

Hyperinsulinemia and tinnitus: a historical cohort.

Tinnitus affects millions of people worldwide, and it signals the presence of several underlying diseases, including hyperinsulinemia. The aim of this study was to evaluate the response to dietary treatment in 80 patients with associated tinnitus and hyperinsulinemia. On the basis of data obtained by a questionnaire, two groups were established: One included patients who followed the prescribed diet; the other group included patients who did not comply with the treatment. The likelihood of improving tinnitus symptoms was fivefold higher in hyperinsulinemic patients who followed the diet than in those who did not (relative risk [RR], 5.34; 95% confidence interval [CI], 1.85-15.37; p < .05). In addition, resolution of tinnitus was reported by 15% of the patients who followed the diet as compared to 0% of those who did not. These findings underscore the importance of including hyperinsulinemia in the routine diagnostic investigation of patients with tinnitus regardless of whether associated with neurosensory dysacusis or vertigo (or both).

Cirurgia da surdez profunda: riscos do implante coclear / Surgery of profound hearing loss: risks of cochlear implantation

O implante coclear tem se consolidado como a terapêutica de escolha de pacientes com surdez neurossensorial profunda bilateral que obtêm pouco ou nenhum benefício com o uso de aparelhos de amplificaçäo sonora. Os pacientes säo selecionados para a introduçäo do implante com base em critérios clínicos, audiológicos e psicológicos. A despeito da criteriosa seleçäo dos candidatos ao implante, existe a possibilidade de insucesso e de complicaçöes cirúrgicas. O presente trabalho objetiva discutir os principais riscos associados ao implante coclear, salientando o mecanismo de injúria potencialmente envolvido

Limitaçöes do implante coclear / Limitations of the cochlear implant

O implante coclear tem se consolidado como o tratamento de escolha de pacientes com hipoacusia profunda bilateral que obtÛm pouco ou nenhum benefÝcio com os aparelhos de amplificaçÒo sonora. A despeito dos inegßveis avanços nessa ßrea, a utilizaçÒo dos implantes cocleares Ú ainda limitada por determinadas condições capazes de comprometer a segurança do ato cirúrgico ou, mesmo, a eficßcia do implante. O presente trabalho objetiva discutir as principais limitações associadas ao implante coclear.