“…Patient symptoms and long-term outcomes may depend on the location of the misplaced electrode. Patients with cochlear implant misplacement in the vestibular system may present with severe vertigo, nystagmus, or vomiting either immediately postoperatively or at the time of device activation (2,8,14,18,32). IAC misplacement poses significant risk of damage to the auditory and facial nerves, potentially resulting in facial paralysis and poor long-term CI performance following revision due to damage of the auditory nerve within the IAC.…”
Section: Discussionmentioning
confidence: 99%
“…While seven electrodes were placed in the internal carotid canal, no patient experienced significant vascular injury (3,4,9,11,16,17). Misplacement in the internal auditory canal was rare, and typically occurred through the modiolus via either a congenital or acquired defect, as two of the four cases were noted to have incomplete partition (3,8,11,12).…”
Section: Discussionmentioning
confidence: 99%
“…Electrode array misplacement is a rare but serious complication that has been predominantly reported in individual case reports and case series by various authors, occurring in 0.20 to 5.88% of implantations (1)(2)(3)(4)(5)(6)(7). Common locations for misplaced electrode arrays include the vestibule, hypotympanum, and internal carotid canal (3,8,9). Typical consequences of misplacement include lack of auditory perception, vertigo, damage to adjacent neurovascular structures, and need for revision surgery (8).…”
Objective:To determine root causes leading to misplaced cochlear implant (CI) electrode arrays and discuss their management using a case series and contemporary literature review.Study Design:Retrospective case review and contemporary literature review.Setting:Single tertiary-referral center.Patients:Adult and pediatric patients who were diagnosed with a misplaced CI electrode array, excluding tip-foldover. Literature review was performed via a MEDLINE database PubMed query. All articles that described at least one case of extracochlear electrode array misplacement were included; partial insertions and extrusions were excluded.Main Outcome Measure:Extracochlear misplacement.Results:A total of 61 cases were reviewed, including 4 new cases and 57 cases from 29 previously published articles. We discuss management of CI arrays in the carotid canal, the vestibule, and the modiolus. The rate of CI misplacement is estimated to be 0.49%. The most frequent location of misplacement CI was the vestibular system (50.8%) followed by the internal carotid canal (11.5%). Normal cochlear anatomy was noted on preoperative computer tomography (CT) in 59.0% of patients; abnormalities were noted in 27.9%. The most common technical issue was misidentification or poor visualization of the round window.Conclusion:CI electrode misplacement is rare but can cause postoperative complications and may result in permanently diminished CI performance and hearing outcomes, even after revision surgery. Failure to identify the round window is the most common reason for CI misplacement, despite most patients having normal cochlear anatomy. Surgical strategies to localize the round window and basal turn are imperative for proper electrode placement.Level of Evidence:4.
“…Patient symptoms and long-term outcomes may depend on the location of the misplaced electrode. Patients with cochlear implant misplacement in the vestibular system may present with severe vertigo, nystagmus, or vomiting either immediately postoperatively or at the time of device activation (2,8,14,18,32). IAC misplacement poses significant risk of damage to the auditory and facial nerves, potentially resulting in facial paralysis and poor long-term CI performance following revision due to damage of the auditory nerve within the IAC.…”
Section: Discussionmentioning
confidence: 99%
“…While seven electrodes were placed in the internal carotid canal, no patient experienced significant vascular injury (3,4,9,11,16,17). Misplacement in the internal auditory canal was rare, and typically occurred through the modiolus via either a congenital or acquired defect, as two of the four cases were noted to have incomplete partition (3,8,11,12).…”
Section: Discussionmentioning
confidence: 99%
“…Electrode array misplacement is a rare but serious complication that has been predominantly reported in individual case reports and case series by various authors, occurring in 0.20 to 5.88% of implantations (1)(2)(3)(4)(5)(6)(7). Common locations for misplaced electrode arrays include the vestibule, hypotympanum, and internal carotid canal (3,8,9). Typical consequences of misplacement include lack of auditory perception, vertigo, damage to adjacent neurovascular structures, and need for revision surgery (8).…”
Objective:To determine root causes leading to misplaced cochlear implant (CI) electrode arrays and discuss their management using a case series and contemporary literature review.Study Design:Retrospective case review and contemporary literature review.Setting:Single tertiary-referral center.Patients:Adult and pediatric patients who were diagnosed with a misplaced CI electrode array, excluding tip-foldover. Literature review was performed via a MEDLINE database PubMed query. All articles that described at least one case of extracochlear electrode array misplacement were included; partial insertions and extrusions were excluded.Main Outcome Measure:Extracochlear misplacement.Results:A total of 61 cases were reviewed, including 4 new cases and 57 cases from 29 previously published articles. We discuss management of CI arrays in the carotid canal, the vestibule, and the modiolus. The rate of CI misplacement is estimated to be 0.49%. The most frequent location of misplacement CI was the vestibular system (50.8%) followed by the internal carotid canal (11.5%). Normal cochlear anatomy was noted on preoperative computer tomography (CT) in 59.0% of patients; abnormalities were noted in 27.9%. The most common technical issue was misidentification or poor visualization of the round window.Conclusion:CI electrode misplacement is rare but can cause postoperative complications and may result in permanently diminished CI performance and hearing outcomes, even after revision surgery. Failure to identify the round window is the most common reason for CI misplacement, despite most patients having normal cochlear anatomy. Surgical strategies to localize the round window and basal turn are imperative for proper electrode placement.Level of Evidence:4.
“…Despite of the multiplanar visualization of the anatomical spaces and depth perception provided by the microscope, it sometimes does not allow full visualization of the RW niche [13,19]. In some occasions with abnormal pneumatization of the facial recess air cells with narrow posterior tympanotomy, prominent sigmoid sinus, temporal bone and facial nerve malformations, and cases with previous otological procedures; conventional surgery with posterior tympanotomy gets very difficult to achieve and surgeon can face great risks of injury to the facial nerve, the ossicular chain or TM, or may lead to misplacement of the electrode array into an abnormal extracochlear site [10,11,20]. When we incorporate the endoscope in such difficult cases, visualization and maneuverability get much better and offer the surgeon a tremendous help to achieve his goal in a much better way with less risks or complications.…”
Background
The aim of this study is to discuss the detailed surgical steps of the endoscopic-assisted epi-tympanic approach (EAEA) to the round window (RW) as a safe, precise, and reliable approach for cochlear implantation (CI) and also to evaluate possible problems and limitations faced, their management strategies, and how to overcome.
Results
This study was carried on 40 patients admitted for cochlear implantation (CI). The patients were divided into two equal groups; the first group underwent CI via the endoscopic-assisted epitympanic approach (EAEA), while the second group was a comparison group and underwent CI via the classic posterior tympanotomy. There was a statistical significant difference as regards scalar location of CI electrodes; all EAEA cases were inserted through ST in comparison to 45% of conventional cases. There was no statistical significant difference as regards linear and angular insertion depth between the two groups. The EAEA group needed shorter time to finish the procedure taking from 90 to 195 min, whereas the conventional group consumed longer time ranging from 120 to 185 min; a difference that was found to be statistically significant. No facial nerve injury was reported in the endoscopic approach.
Conclusions
Endoscope-assisted epitympanic approach (EAEA) is a reliable and safe approach for soft surgery CI. Visualization of the RW and insertion of the electrode under endoscopic control was significantly reliable and successful in all cases.
“…The electrode array enters into the internal auditory canal or may form a more basal slope within the internal auditory canal. The condition of an incomplete partition type III is a risk factor, since there is no bony separation between cochlea and internal auditory canal [ 69 , 70 ]. Fig.…”
Cochlear implants are increasingly used to treat sensorineural hearing disorders in both children and adults. Pre-operative computed tomography and magnetic resonance imaging play a pivotal role in patient selection, to rule out findings that preclude surgery or identify conditions which may have an impact on the surgical procedure. The post-operative position of the electrode array within the cochlea can be reliably identified using cone-beam computed tomography. Recognition of scalar dislocation, cochlear dislocation, electrode fold, and malposition of the electrode array may have important consequences for the patient such as revision surgery or adapted fitting.
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