Advancing Cochlear Implant Programming: X-ray Guided Anatomy-Based Fitting.

BACKGROUND: Anatomy-based fitting (ABF) is a new research area in the field of cochlear implants (CIs). Despite the reported benefits and acceptable levels of ABF among CI recipients, some limitations remain, like the postoperative computed tomography (CT) scan, which is preferred for confirming electrode array insertion. OBJECTIVE: This study aimed to investigate the feasibility of using plain film radiography (X-ray) for postoperative electrode detection and for building ABF as an alternative to CT. METHODS: A total of 53 ears with CI were studied. All cases had routine post-insertion X-rays in the cochlear view and additionally underwent postoperative CT. The insertion angles and center frequencies measured by two independent observers were compared for each imaging modality. The angular insertion depth and center frequencies resulting from the X-ray and CT scans were then compared. RESULTS: No significant differences were observed between the X-ray- and CT-measured angles for the electrode contacts. Radiographic measurements between the two readers showed an almost perfect (≥0.8) or substantial (0.71) intraclass correlation coefficient along the electrode contacts. X-ray images showed a mean difference of 4.7 degrees from CT. The mean semitone deviation of the central frequency between the CT and X-ray images was 0.6. CONCLUSIONS: X-ray imaging provides a valid and easy-to-perform alternative to CT imaging, with less radiation exposure and lower costs. The radiographs showed excellent concordance with the CT-measured angular insertion depth and consequently with the central frequency for most electrode contacts. Therefore, plain X-ray could be a viable alternative in building ABF for the CI recipients.

Cochlear implantation in adults and pediatrics with enlarged vestibular aqueduct: a systematic review on the surgical findings and patients' performance.

PURPOSE: Cochlear implantation (CI) has been considered a safe and effective management option for patients with severe to profound hearing loss. Patients with enlarged vestibular aqueduct (EVA) could be challenging with some variations in surgical approaches, intraoperative surgical notes, and clinical outcomes. This study aimed to  review the surgical and clinical outcomes of cochlear implantation among patients with EVA. MATERIALS AND METHODS: A systematic literature search was carried out in five major databases. All original studies reporting cochlear implantation in patients with EVA were included for qualitative data synthesis. The risk of bias was independently assessed through the National Intuitional of Health tool. The review protocol was registered in PROSPERO (reference number: CRD42021225900). RESULTS: A total of 34 studies with 4035 subjects were included. Of them, 853 (21.14%) had EVA and underwent CI. Mondini malformation was the most frequently associated anomaly (n = 78, 11.1%). Unilateral implantation was performed in 258 cases while bilateral in 119 subjects. Postoperative complications included CSF/perilymph gusher (n = 112), CSF oozing (n = 18), and partial electrode insertion (n = 6). Closing the cochleostomy with temporalis fascia, muscle, connective tissue, or fibrin glue was the most frequently reported approach to manage CSF/perilymph gusher (n = 67, 56.7%) while packing was performed in six patients. CONCLUSION: Patients with EVA demonstrated audiometric and speech performance improvement after CI. However, many patients had intra- or postoperative complications. Further research is needed as the outcomes may be affected by associated temporal bone pathology, the timing of implant, and hearing condition.

Magnet and receiver-stimulator displacement after cochlear implantation: Clinical characters and management approaches.

OBJECTIVES: To systematically review the occurrence of magnet or receiver/stimulator displacement following cochlear implant (CI) placement complication and evaluate the existing literature on this topic. METHODS: A systematic literature search was conducted using PubMed, Scopus, Web of Science, Virtual Health Library (VHL), and Cochrane Library. Original studies reporting cases of magnet or receiver-stimulator migration occurring as a complication after CI placement were included. The quality of the included studies was evaluated using the National Institutes of Health Quality Assessment Tool for observational studies and CARE checklist for case studies. RESULTS: A total of 36 studies, including 6469 patients, were included. Magnet migration was reported in 82 (1.3%) patients, while receiver/stimulator was reported in 4 (0.1%) cases. The cause of magnet migration was identified in 78 cases; MRI-induced movement was the most frequently reported cause (n=43, 55.1%), followed by head trauma (n=25, 32.1%). A total of 20 studies involving 35 patients with magnet migration performed skull radiography to diagnose magnet migration. Revision/exploratory surgery with surgical repositioning or replacement was the most frequent management procedure (n=46). CONCLUSIONS: Further research on magnet pocket design and standard protocols for MRI in CI users is needed. Early diagnosis of magnet migration and instant referral to specialized CI centers is necessary for proper management and prevention of major complications. PROSPERO REG. NO. CRD: 42020204514.