Comparison of Video Nasopharyngoscopy and Tympanometry in Suspected Eustachian Tube Dysfunction - A Prospective Study

Objective Tympanometry is widely used for diagnosing Eustachian tube dysfunction (ETD). However, in clinical practice, it is not uncommon to come across patients with symptoms of ETD with a normal tympanogram. Dynamic slow motion video endoscopy (DSMVE) of Eustachian tube (ET) and Eustachian tube dysfunction questionnaire-7 (ETDQ-7) are other tools to diagnose ETD. Primary aim of the study was to compare DSMVE and tympanometry in diagnosing ETD. Secondary objective was to find an association between DSMVE and ETDQ-7. It was a prospective diagnostic validity study in the department of Otorhinolaryngology at a tertiary care centre. Patients with symptoms suggestive of ETD with intact tympanic membrane (TM) and aged above 12 years were evaluated. The study duration was 17 months. The parameters assessed were tympanic membrane(TM) retraction by otoscopy, DSMVE, tympanometry and ETDQ-7 questionnaire. To test the significance of association and difference between tympanogram and nasopharyngoscopy, Chi-Square t test and McNemar's tests were applied. Out of 107 ears, DSMVE, tympanometry, ETDQ- 7 and otoscopy detected ETD in 51, 31,70 and 57 ears respectively. DSMVE and tympanometry together detected ETD in 29 ears and did not detect in 54 ears. Both these diagnostic methods were not comparable statistically (moderate agreement- Kappa value- 0.542). Comparison of DSMVE with ETDQ-7 was statistically significant (p-value- 0.004). Video nasopharyngoscopy cannot be a stand- alone diagnostic aid for ETD. ETDQ-7 questionnaire showed higher concordance with nasopharyngoscopy than tympanometry. Diagnostic accuracy was more when all four parameters were assessed together.