MIDDLE-EAR FUNCTION IN RHEUMATOID-ARTHRITIS - A MULTIPLE FREQUENCY TYMPANOMETRIC STUDY

Objective: To evaluate the modifications in the mechanical properties of the middle ear in rheumatoid arthritis by assessing its resonance f requency. Methods: Thirty patients with rheumatoid arthritis (RA) aged 20 to 68 years (mean age 45.8 +/- 12.4 yrs) were investigated by mult iple frequency tympanometry and their data were compared with those ob tained in a control group of 48 subjects aged from 19 to 65 years. Res ults: Normal values, calculated at the 95th percentile from the contro l group, ranged from 800 to 1250 Hz. Eleven RA patients (36.6%) displa yed abnormal resonance values. These findings were monolateral in 9 pa tients and bilateral in 2 (in all a total of 13 ears). Nine out of 13 ears with abnormal multiple frequency tympanometry data were character ized by an increase in resonance and 4 by a decrease. Conclusion: Thes e findings were attributed to abnormal acoustic impedence of the middl e ear and indicate a possible involvement of the ossicular diarthroses in RA. Our study suggests that RA may involve the incudo-malleolar an d incudo-stapedial joints, altering the ossicular mechanisms in respon se to static air pressure modifications.