Endoscopic findings and long-term hearing results for pediatric unilateral conductive hearing loss.

Objectives: Analyze reasons for unilateral conductive hearing loss (CHL) with unknown etiology in children.

Introduction: Unilateral conductive hearing loss (HL) without known etiology can be undiagnosed despite of hearing screening programs. It can be difficult to find the reason for HL and to make a treatment plan. Middle ear endoscopy gives hard-evidence diagnosis and basis for an individual treatment plan.

Methods And Material: Prospective clinical follow-up study for a cohort of generally healthy elementary school age children with unilateral conductive HL with unknown etiology. The study population was 192 children, of which 46 had a HL of at least 25 dB with more than 10 dB conductive component. Mean age was 8.7 years. Preoperative tests included otomicroscopy, bone- and air-conduction audiogram, tympanometry, stapes reflex tests, Rinne and Weber test and Otoacoustic emissions. The children underwent endoscopy of the middle ear with an individual treatment plan and long-term follow-up. The aim was to explore etiology and to give a treatment plan for hearing loss. Follow-up included air- and bone conduction hearing tests annually or every other year. Mean follow-up was 5.2 years.

Results: A clear etiological finding was found in 36 (78%) ears, stapes anomaly (23) as the most common (64%) finding. Other findings were two cholesteatomas, 2 status after trauma, 5 middle ear anomalies, 5 incus fixations and one incus erosion. Air conduction hearing improved spontaneously during follow-up in 81% (17/21, 2 dropouts) of the stapes anomaly ears (mean 11,3 dB, range 4-32 dB), and none of these ears showed hearing deterioration. In the incus fixation group, one ear showed hearing deterioration. There were no major complications for exploration, and 5 minor postoperative infections.

Conclusions: The most common reason for pediatric unilateral conductive hearing loss was stapes anomaly/fixation. The HL does not deteriorate. Hearing loss in stapes anomalies shows a tendency for spontaneous recovery. Stapes surgery can be postponed or avoided.