Middle ear effusion: tympanometry versus operative findings

Objective: To evaluate the role of tympanometry in predicting middle ear effusion by comparing results with the operative findings.Design: A descriptive study concerned with 105 ears (57 patients) diagnosed as middle eareffusion by tympanometry; type B, flat curve; that underwent myringotomy operation (with or without ventilation tube insertion).setting: Department of ENT-Al-salam Teaching Hospital/Mosul for the period (April 2003 to September 2004). Tympanometry was performed in the Outpatient Clinic of Al-JamhooriTeaching Hospital.Subjects: The study included 36 males and 21 females with a ratio of 1.7:1. The average agewas 6 years with a range of 3-12 years.Methods: The parameters analyzed included age, sex and tympanometric results. Matchingbetween the suspected ears for middle ear effusion; type B, flat curve; and the operativefindings (fluid found in the middle ear at the time of myringotomy) was recorded.Results: The diagnostic accuracy and examination success rate of tympanometry; type B, flatcurve; in predicting middle ear effusion was 71.4%. Moreover, the sensitivity, specificity, positive and negative predictive values were 97.2% , 57.3%,55.3% and 97.5% respectively. Thus, the positive likelihood ratio was 2.3.Conclusion: The accuracy rate of tympanometry in predicting middle ear effusion showed a fair validity for its exclusion. The use of pneumatic otoscopy and tympanometry together improves the accuracy of diagnosis.Key words: Tympanometry, middle ear effusion, myringotomy.