Long‐term cochlear implantation outcomes in patients following head injury

Abstract

ObjectiveIn cases of a severe to profound sensorineural hearing loss following head injury, the cochlear implant (CI) is the primary option for auditory rehabilitation. Few studies, however, have investigated long‐term CI outcomes in patients following head trauma, including those without temporal bone fracture (TBF). Herein, the aim of this study is to examine CI outcomes following cases of head injury with and without TBF.MethodsAudiometric outcomes of patients who received a CI due to a head injury resulting in severe to profound hearing loss at two tertiary care hospitals were analyzed. Patients were divided into those who received a CI in a fractured temporal bone (group A, n = 11 patients corresponding to 15 ears) and those who received a CI in a non‐fractured temporal bone (group B, n = 8 patients corresponding to nine ears). Primary outcomes included duration of deafness prior to CI and postoperative consonant‐nucleus‐constant whole word (CNC) scores.ResultsNineteen patients (84% male), corresponding to 24 CIs, were identified. Fifteen CI were performed on ears with TBF (group A), and nine CI were performed on ears without TBF (group B). No patients had an enlarged vestibular aqueduct (EVA). The mean duration of deafness was 5.7 and 11.3 years in group A and group B, respectively. The mean duration of CI follow‐up (CI experience) was 6.5 years in group A and 2.1 years in group B. The overall mean postoperative CNC score for all subjects was 68.6% (±21.2%, n = 19 with CNC testing). There was no difference in CNC score between group A and group B (69.8% and 66% respectively, P = .639).ConclusionThe study is among the largest series examining long‐term outcomes of CI after head injury. CI is an effective method for auditory rehabilitation in patients after head injury.Level of evidenceIV.

Bilateral Cochlear Implantations in Temporal Bone Fracture: A Viable Treatment Option

“…This is consistent with previous findings demonstrating that the onset of hearing loss following head trauma could be sudden or delayed 22,23 . Indeed, knowing the time course between the trauma and onset of hearing loss is important to ensure the stability of hearing levels, as the hearing thresholds might recover depending on the extent and type of injury 19,24 . However, the onset of hearing loss could not be determined for some of our patients as they needed intubation and mechanical ventilation during their stay in the ICU.…”

“…Individuals who sustain bilateral TBF may present with different case profiles, depending on the extent and site of the damage 5,19 . In this study, four patients had hearing loss with no other symptoms; one female child had a history of generalized weakness after trauma, one patient had impaired balance and right‐sided facial weakness, and another had blindness and multiple head injuries, in addition to profound hearing loss.…”

“…22,23 Indeed, knowing the time course between the trauma and onset of hearing loss is important to ensure the stability of hearing levels, as the hearing thresholds might recover depending on the extent and type of injury. 19,24 However, the onset of hearing loss could not be determined for some of our patients as they needed intubation and mechanical ventilation during their stay in the ICU. Therefore, given that hearing loss is widely reported in patients with TBF, it is important to recommend objective hearing evaluations for unconscious patients with head trauma, particularly for those with evidence of TBF involving the otic capsule.…”

“…Hearing loss resulting from bilateral TBF is typically managed with a cochlear implant in the ear with less damage, to maximize the success of the procedure. Variable implantation outcomes have been described in this population 1,[18][19][20] ; however, the feasibility of bilateral CI in patients with bilateral TBF has not been investigated. The benefits of bilateral CI have been widely demonstrated to include improvement in sound source localization and hearing in noise, and providing release from masking, binaural summation, and squelch effects.…”