Audiological characteristics of the contralateral ear in patients with unilateral physical non-explosive ear trauma

To document the frequency of occurrence and types of symptoms experienced in the contralateral ear in patients with unilateral physical non-explosive (UPN) ear trauma and to compare the audiometric and tympanometric parameters between asymptomatic and symptomatic contralateral ears.

Prospective analytical clinical study Setting: Specialized (Ear, Nose, and Throat) clinic of a tertiary health institution. Participants: Patients with UPN ear trauma who presented within the first week of the incident. Main outcome measures: Otologic symptoms in the contralateral ear in UPN ear trauma.

Eighteen out of 53 patients (34.0%) experienced symptoms in the contralateral ear. The symptoms were tinnitus in 77.8% (14/18), hearing loss in 66.7% (12/18), and ear blockage in 27.8% (5/18). There was hearing loss in 38/53 (71.7%) of contralateral ears. Hearing loss type and PTAv at the low frequencies were not significantly different (p=0.142), but other audiometric parameters were significantly different between asymptomatic and symptomatic contralateral ears (p<0.05 in all). Type C tympanogram was more prominent in the symptomatic contralateral ear. There was a statistically-significant difference in the type of tympanogram between the two categories of patients (p=0.018). There was no difference in acoustic reflex between the two categories of patients (p=0.095).

The contralateral ear may be affected in up to one-third of patients with UPN ear trauma, and experience otologic symptoms similar to those of the traumatized ears. Audiologic and audiometric parameters were abnormal in most of the contralateral ears. The two ears must be assessed thoroughly in cases of UPN ear trauma.