Purpose To evaluate the insertion results and hearing preservation of a novel slim modiolar electrode (SME) in patients with residual hearing. Methods We retrospectively collected the data from the medical files of 17 patients (18 ears) implanted with a SME. All patients had functional low frequency hearing (PTA (0.125-0.5 kHz) ≤ 80 dB HL). The insertion results were reexamined from the postoperative cone-beam computed tomography scans. Postoperative thresholds were obtained at the time of switch-on of the sound processors (mean 43 days) and at latest follow-up (mean 582 days). The speech recognition in noise was measured with the Finnish matrix sentence test preoperatively and at follow-up. Results The mean insertion depth angle (IDA) was 395°. Neither scala dislocations nor tip fold over were detected. There were no total hearing losses. Functional low-frequency hearing was preserved in 15/18 (83%) ears at switch-on and in 14/17 (82%) ears at follow-up. According to HEARRING classification, 55% (10/18) had complete HP at switch-on and 41% (7/17) still at follow-up. Thirteen patients (14 ears) were initially fitted with electric-acoustic stimulation and seven patients (8 ears) continued to use it after follow-up. Conclusions The preliminary hearing preservation results with the SME were more favorable than reported for other perimodiolar electrodes. The results show that the array may also be feasible for electro-acoustic stimulation; it is beneficial in that it provides adequate cochlear coverage for pure electrical stimulation in the event of postoperative or progressive hearing loss.

Objectives: To investigate the results of clinical surgical insertions with a Mid-scala array (HIFocus Mid-Scala Electrode, HFms). Study Design: Consecutive retrospective case study. Settings: Tertiary referral center. Patients: Analyses of imaging data of 26 consecutive patients (31 insertions) implanted with the HFms. Intervention (s): The evaluation of insertion trauma evoked by a previously validated image fusion technique. Electrode reconstructions from postoperative cone-beam computed tomography (CBCT) were overlaid onto preoperative magnetic resonance imaging (MRI) scans to create artifact-free images. Main Outcome Measures: The electrode position was quantified in relation to the basilar membrane. Trauma scaling adopted from Eshraghi was used for evaluating insertion trauma. The results of the visual assessment of the postoperative CBCT were compared to those obtained with the fusion technique. Results: Three insertions had to be excluded due to incompatibility of the imaging data with the fusion software. We found consistent peri- to mid-modiolar placement of the HFms with a mean insertion depth angle of 376°. According to the medical records, a visual examination of the postoperative CBCT indicated that there had been no scala dislocations but when assessed by the image fusion technique, five scala dislocations (17.8%) were found. Additionally, one tip fold-over was detected in the postoperative CBCT even though this was not evident in any intraoperative measurements. Conclusion: HFms showed atraumatic surgical insertion results with consistent mid-modiolar placement. Image fusion enhances the accuracy of the insertion trauma assessment. Routine postoperative imaging is recommended for identifying tip fold-over as well as for quality control and documentation.

The SMA showed consistent and atraumatic insertion results in TBs. Pre- and postimplant cone beam computed tomography with image fusion was shown to be very accurate for the assessment of electrode position and insertion trauma.

Purpose Consumer-grade virtual reality (VR) has recently enabled various medical applications, but more evidence supporting their validity is needed. We investigated the accuracy of simulated surgical planning in a VR environment (VR) with temporal bones and compared it to conventional cross-sectional image viewing in picture archiving and communication system (PACS) interface. Methods Five experienced otologic surgeons measured significant anatomic structures and fiducials on five fresh-frozen cadaveric temporal bones in VR and cross-sectional viewing. Primary image data were acquired by computed tomography. In total, 275 anatomical landmark measurements and 250 measurements of the distance between fiducials were obtained with both methods. Distance measurements between the fiducials were confirmed by physical measurement obtained by Vernier caliper. The experts evaluated the subjective validity of both methods on a 5-point Likert scale qualitative survey. Results A strong correlation based on intraclass coefficient was found between the methods on both the anatomical (r > 0.900) and fiducial measurements (r > 0.916). Two-tailed paired t-test and Bland–Altman plots demonstrated high equivalences between the VR and cross-sectional viewing with mean differences of 1.9% (p = 0.396) and 0.472 mm (p = 0.065) for anatomical and fiducial measurements, respectively. Gross measurement errors due to the misidentification of fiducials occurred more frequently in the cross-sectional viewing. The mean face and content validity rating for VR were significantly better compared to cross-sectional viewing (total mean score 4.11 vs 3.39, p < 0.001). Conclusion Our study supports good accuracy and reliability of VR environment for simulated surgical planning in temporal bones compared to conventional cross-sectional visualization.