목적: The electrical auditory brainstem response (EABR), which is performed to evaluate auditory function in hearing loss patients, has been performed by promontory stimulation. This is mainly used for the prediction of the cochlear implant outcomes preoperatively, but the results are unsatisfactory in terms of accuracy and reproducibility. In this study, postoperative intracochlear EABR results were compared with those of conventional testing methods and CI outcome. This study shows that postoperative intracochlear EABR can be more effective than conventional EABR methods for prediction of CI outcome. 방법:A retrospective study is performed based on the medical records of patients who underwent cochlear implants with hearing loss at Seoul National University Bundang Hospital. The medical records confirm the patient's etiology, preoperative pure tone audiometry test, promontory stimulation EABR, postoperative electrically evoked compound action potential (ECAP), postoperative EABR, and speech evaluation results after cochlear implantation. 결과:A total of six patients were analyzed in this study. Two of the congenital hearing loss patients were auditory neuropathy spectrum disorder, two were cochlear nerve aplasia and one was cochlear aplasia. The other one had deafness due to labyrinthine infarction. In patients with cochlear nerve aplasia, cochlear aplasia and labyrinthine infarction, ECAP and postop EABR results predicted CI outcomes relatively well. On the other hand, the results of ECAP and postop EABR in patients with ANSD did not agree with the outcome of CI. 결론:ECAP and postop intracochlear EABR may be useful in predicting CI outcome in patients with cochlear nerve disorder and inner ear anomaly. On the other hand, in two patients with ANSD with anatomically intact cochlear nerve, ECAP, postop EABR and CI outcomes were inconsistent. There is a large difference in deaf duration between these two patients, and further studies are needed to determine the cause of the discrepancy.