RESUMEN
Key Clinical Message: In young infants, under the age of one-year, cochlear malformation with profound hearing loss complicated by a perilymphatic fistula (PLF), presents a serious clinical challenge, warranting immediate audiological and surgical intervention. Timely PLF detection and closure, along with an early CI can significantly improve the prognosis of such patients and helps them in achieving their maximum hearing and developmental potential, in the long term. Abstract: Inner ear malformation (IEM) with incomplete partition and cystic cochlea is mostly accompanied by profound hearing loss. It gets further complicated with other malformations such as a perilymphatic fistula (PLF). This case concerns an 8-month-old child cochlear malformation and profound hearing loss. Surgical intervention identified a PLF at the stapedial footplate, which was successfully closed. The surgery also included the placement of a cochlear implant (CI) in the right ear, via the round window. The left ear was equipped with hearing aids, with persistent hearing thresholds at 70-80 db. At the age of 6 years, the child showed a good hearing outcome with the CI, with only moderate speech delay. Cochlear malformation accompanied by a perilymphatic leakage warrants immediate surgical closure of the PLF, to minimize the risk of bacterial meningitis. Wherever possible, the feasibility of a CI should be explored in such cases and a CI should be placed for treatment of hearing loss. Audiological and speech outcomes may vary with the use of the CI, especially in cases of IEM. However, an early CI coupled with timely PLF detection and closure can help children with profound hearing loss, in achieving their maximum hearing and developmental potential, in the long run.
RESUMEN
OBJECTIVE: Subjective promontory stimulation is used to evaluate cochlear implant (CI) candidacy, but the test reliability is low. Electrically evoked auditory brainstem response (EABR) can verify the function of the auditory system objectively. This study's procedure uses a trans-tympanic rounded bent-tip electrode to perform pre-operative EABR under local anaesthesia (LA-TT-EABR) using MED-EL Software and Hardware. This study aimed to determine usability and effectiveness for CI candidates. DESIGN: We hypothesised that LA-TT-EABR waveforms of good quality would be related to successful hearing outcomes. We assumed that the duration of hearing loss/deafness was a confounding factor to study outcomes. STUDY SAMPLE: 19 borderline CI candidates. RESULTS: Positive LA-TT-EABR results were confirmed in 14 patients. LA-TT-EABR's mean latency was 2.05 ± 0.31 ms (eII/eIII) and 4.24 ± 0.39 ms (eIV/eV). Latencies weren't statistically different from intra-operative EABR elicited by basal CI contacts. All positive LA-TT-EABR patients benefitted from CI and speech performance improved one year after implantation. One patient with negative LA-TT-EABR was cochlear-implanted and had no hearing sensation. CONCLUSIONS: LA-TT-EABR is a tool in the frame of pre-operative objective testing the auditory pathway. It seems useful for clinical testing CI candidacy. Based on this study's outcomes, LA-TT-EABR should be recommended for uncertain CI candidates.