Non-Expensive blast injury of the tympanic membrane in Umuahia, Nigeria

Abstract

To examine the clinical features and causes of non-explosive blast injury to the ear, as well as the frequency of the State police involvement. Prospective clinical study of consecutive patients with traumatic tympanic membrane perforations resulting from non-explosive blast trauma to the ear without history of previous middle ear disease who attended ENT clinic of Federal Medical Center Umuahia. Clinical features and causes of non-explosive blast injury to ear; healing outcome at 2, 4, 8, and 12 weeks; perforation size versus healing outcome and cause of injury were the main outcomes measured. Five hundred and ninety three new patients with aural disease were analysed. Sixty-one patients, (38 males and 23 females), aged 10-56 years had tympanic membrane perforation from non-explosive blast injury to the ear. The commonest symptoms were hearing loss (64%), tinnitus (61%), and ear ache (57%). The causes of injury were: slap against the ear by State police (31%), spouse (28%), armed bandits (18%), school teachers (8%), parents (5%), and blow against the ear during street fight (10%). Ninety two percent of the perforations healed spontaneously Healing was associated with significant closure of air bone gap (t = 15.08; p < 0.01). Non-healing of perforation was significantly associated with the large perforations occupying estimated 50% or more of the entire tympanic membrane area (chi2 = 8.67; p = 0.003). The ear is very susceptible to injury from non-explosive blast trauma. There was a high spontaneous healing rate of the resulting tympanic membrane perforation, favoring conservative management in most of the case. Non-healing was associated with large-sized perforations. Abusive slap by the State police men was the commonest cause of non-explosive blast injury to the tympanic membrane. Our results are hoped to stimulate a change in the attitude of the culprits and lead to a reduction in the incidence of avoidable TM perforations from slap assaults.