Hearing dynamics in patients with traumatic tympanic membrane perforation.

Background: Hearing distortions from trauma to the ear could occur by direct perforation of the tympanic membrane.

Aim: To characterize hearing thresholds in patients with traumatic tympanic membrane perforation and changes in hearing occurring in the course of treatment.

Study design: Prospective analytical study.

Setting: Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria.

Methodology: We prospectively entered in a proforma the demographics of 60 patients with traumatic tympanic membrane perforation at the teaching hospital in Sagamu, Nigeria over a period of five years as well as their hearing assessment with pure tone audiometry at initial contact and six weeks post-injury. The type of hearing loss, pure tone average and air-bone gaps were recorded. Hearing changes between initial and second audiometric assessments were analyzed and compared.

Results: The data obtained from 60 patients with 73 traumatized ears were analyzed. In all, 64 (87.7%) of the ears had hearing loss while 33(45.2%) had conductive hearing loss. Injured ears had significantly worse hearing and higher air-bone gaps ABGs compared with non-traumatized ears. There was notable improvement in hearing thresholds and closure of air-bone gaps in the course of treatment, which was significantly more at the low frequencies compared with the high frequencies.

Conclusion: Patients with traumatic tympanic membrane perforation majorly had conductive hearing loss in the injured ears with audiometric confirmed air-bone gaps and increased hearing thresholds which were not frequency dependent. There was appreciable improvement in hearing parameters over time, significantly more at the low frequencies.