Norio Yamamoto1, Takayuki Okano1, Hiroshi Yamazaki2, Harukazu Hiraumi3, Tatsunori Sakamoto4, Juichi Ito5, Koichi Omori1. 1. Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto. 2. Department of Otolaryngology-Head and Neck Surgery, Osaka Red Cross Hospital, Osaka. 3. Department of Otolaryngology-Head and Neck Surgery, Iwate Medical University, Morioka. 4. Department of Otolaryngology-Head and Neck Surgery, Kitano Hospital, Osaka. 5. Shiga Medical Center Research Institute, Moriyama, Japan.
Abstract
OBJECTIVE: To evaluate the electrode status during cochlear implantation (CI) using mobile cone-beam CT (mCBCT). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral hospital. PATIENTS: Fifty-seven patients (7 bilateral surgeries, 64 ears) who underwent CI and who received intraoperative mCBCT imaging. INTERVENTION: CI and CBCT during surgery. MAIN OUTCOME MEASURE: Electrode location and angular insertion depth determined by intraoperative mCBCT images. RESULTS: There were six cases with cochlear malformation where intraoperative mCBCT was useful to confirm electrode location. Of 58 ears with a normal cochlear morphology, perimodiolar, straight, and mid-scalar electrodes were used in 30 (cochleostomy; 14 advance off-stylet technique cases), 27 (26 round window [RW] insertion, 1 extended round window [ERW] insertion), and 1 (RW insertion) ears, respectively. Complete scala-tympani (ST) insertion was achieved in 35 ears (14 cochleostomy, 21 RW or ERW insertion). The complete ST-insertion rate was significantly higher with RW or ERW insertion than that for cochleostomy insertion (p = 0.03), although cochleostomy insertion using the advanced off-stylet technique had a similar rate to RW or ERW insertion. The angular insertion depth values (average ± standard deviation) for perimodiolar electrodes (354.4 ± 29.44 degrees) were significantly smaller than those for Flex24 (464.8 ± 43.09 degrees) and Flex28 (518.2 ± 61.91 degrees) electrodes (p < 0.05). CONCLUSIONS: Evaluation of CI electrodes using intraoperative mCBCT was comparable to that with fan-beam CT or c-arm-based CBCT. Considering the low radiation dose of mCBCT and its availability in any operation room, mCBCT is the better modality for evaluating cochlear implant electrode arrays.
OBJECTIVE: To evaluate the electrode status during cochlear implantation (CI) using mobile cone-beam CT (mCBCT). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral hospital. PATIENTS: Fifty-seven patients (7 bilateral surgeries, 64 ears) who underwent CI and who received intraoperative mCBCT imaging. INTERVENTION: CI and CBCT during surgery. MAIN OUTCOME MEASURE: Electrode location and angular insertion depth determined by intraoperative mCBCT images. RESULTS: There were six cases with cochlear malformation where intraoperative mCBCT was useful to confirm electrode location. Of 58 ears with a normal cochlear morphology, perimodiolar, straight, and mid-scalar electrodes were used in 30 (cochleostomy; 14 advance off-stylet technique cases), 27 (26 round window [RW] insertion, 1 extended round window [ERW] insertion), and 1 (RW insertion) ears, respectively. Complete scala-tympani (ST) insertion was achieved in 35 ears (14 cochleostomy, 21 RW or ERW insertion). The complete ST-insertion rate was significantly higher with RW or ERW insertion than that for cochleostomy insertion (p = 0.03), although cochleostomy insertion using the advanced off-stylet technique had a similar rate to RW or ERW insertion. The angular insertion depth values (average ± standard deviation) for perimodiolar electrodes (354.4 ± 29.44 degrees) were significantly smaller than those for Flex24 (464.8 ± 43.09 degrees) and Flex28 (518.2 ± 61.91 degrees) electrodes (p < 0.05). CONCLUSIONS: Evaluation of CI electrodes using intraoperative mCBCT was comparable to that with fan-beam CT or c-arm-based CBCT. Considering the low radiation dose of mCBCT and its availability in any operation room, mCBCT is the better modality for evaluating cochlear implant electrode arrays.
Authors: Paul Van de Heyning; Peter Roland; Luis Lassaletta; Sumit Agrawal; Marcus Atlas; Wolf-Dieter Baumgartner; Kevin Brown; Marco Caversaccio; Stefan Dazert; Wolfgang Gstoettner; Rudolf Hagen; Abdulrahman Hagr; Greg Eigner Jablonski; Mohan Kameswaran; Vladislav Kuzovkov; Martin Leinung; Yongxin Li; Andreas Loth; Astrid Magele; Robert Mlynski; Joachim Mueller; Lorne Parnes; Andreas Radeloff; Chris Raine; Gunesh Rajan; Joachim Schmutzhard; Henryk Skarzynski; Piotr H Skarzynski; Georg Sprinzl; Hinrich Staecker; Timo Stöver; Dayse Tavora-Viera; Vedat Topsakal; Shin-Ichi Usami; Vincent Van Rompaey; Nora M Weiss; Wilhelm Wimmer; Mario Zernotti; Javier Gavilan Journal: Front Surg Date: 2022-03-24