Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine, Peoria, IL, United States. Electronic address: zakharel@uic.edu.
The objective of the study was to evaluate the proposed cochlear duct length estimation based on the cochlear 'A value'. Furthermore, we assessed the interobserver variability between radiology and ot...
Thirteen pediatric cochlear implant candidates were retrospectively analyzed by three otolaryngology physicians (attending physician, second year, and fourth year trainees) and a radiology attending. ...
The differences in measurements between the attending otolaryngologist and radiologist were not statistically different, while several significant differences were observed with regard to measurements...
Based on these results, cochlear duct length measurement according to the proposed method may be a reliable and cost-effective method. Indeed, otolaryngology training may be sufficient to provide meas...
Estimating insertion depth, cochlear duct length (CDL), and other inner ear parameters is vital to optimizing cochlear implantation outcomes. Most current formulas use only the basal turn dimensions f...
In cochlear implantation with flexible lateral wall electrodes, a cochlear coverage of 70% to 80% is assumed to yield an optimal speech perception. Therefore, fitting the cochlear implant (CI) to the ...
Retrospective cross-sectional study....
Single-center tertiary referral center....
Patients undergoing cochlear implantation....
Preoperative and postoperative high-resolution computed tomography (HRCT)....
The cochlear duct length was estimated by determining cochlear parameters ( A value and B value), and the AID for the chosen electrode was (i) estimated by elliptic circular approximation by the softw...
A total of 80 HRCT imaging data sets from 69 patients were analyzed. The mean preoperative AID estimation was 662.0° (standard deviation [SD], 61.5°), and the mean postoperatively measured AID was 583...
The use of an electrode visualization tool may lead to shorter electrode array choices because of an overestimation of the insertion angle. Applying a correction factor of 0.95 on preoperative AID est...
Precise electrode positioning is crucial for achieving optimal audiological outcomes in cochlear implantation. The slim modiolar electrode (SME), a thin, flexible, and precurved electrode, exhibits fa...
Retrospective medical record review....
In total, 475 patients (671 ears) underwent cochlear implantation using SMEs (Nucleus CI532 or CI632 from Cochlear) performed by a single surgeon at a tertiary center between June 14, 2018, and Decemb...
Intraoperative x-ray scans (cochlear view), operative records, and cochlear duct length (CDL) were reviewed....
Tip fold-over patterns on plain x-ray images (proximal versus distal)....
Electrode tip fold-over was observed in 18 (2.7%) of the 671 ears with SMEs. This fold-over occurred more frequently in cases with long CDL (>36 mm). Among the 14 cases with available initial x-rays b...
Tip fold-over of SME does not occur uniformly and is more common in ears with long CDL. This tendency is particularly pronounced for the proximal type of tip fold-over. Therefore, preoperative measure...
To achieve better speech performance following cochlear implantation (CI), measuring the patient's cochlear duct length (CDL) and determining the appropriate length of the CI array are important....
To investigate the CDL in CI patients after using the OTOPLAN software preoperatively and compare the results of angular insertion depth (AID) estimation by OTOPLAN and postoperative radiography....
The study included 105 Japanese CI patients with normal cochleae. We measured the CDL using OTOPLAN and the position of the tip channel of the electrode for each selected electrode array, and estimate...
The mean CDL was 35.1 ± 1.6 mm. Preoperatively, the mean estimated AID was 580.3 ± 57.8°. Postoperative radiography revealed a mean AID of 583.0 ± 56.7°, demonstrating a strong linear correlation betw...
Our findings revealed that CDL varies widely, which is consistent with previous studies. To achieve better speech perception, surgeons should select the appropriate length of CI electrode array based ...
Assessment techniques for the cochlear spatial lateral wall are associated with inter-rater variability, but derived clinical recommendations nonetheless offer value for individualized electrode selec...
Anatomical variations influence the location of cochlear implant electrodes inside the cochlea. Preoperative planning allows individualization of the electrode based on characterization of the bony la...
The study used publicly available digitized temporal bones based on microslicing and computed tomography. Four experienced observers assessed the lateral wall applying manual tracing, linear regressio...
Differences were found most pronounced between assessment methods in vertical direction across observers and imaging modalities. One of the five anatomies was consistently found to be of shorter cochl...
Assessment techniques for the bony lateral wall yield method, observer, and image modality related deviations. Automation of the anatomical characterization may offer potential in minimizing inaccurac...
There are clinically relevant differences in scalae anatomy and spiral ganglion neuron (SGN) quantity between incomplete partition type II (IP-II) and normal cochleae....
IP-II is a commonly implanted cochlear malformation. Detailed knowledge of intracochlear three-dimensional (3D) morphology may assist with cochlear implant (CI) electrode selection/design and enable o...
IP-II (n = 11) human temporal bone histological specimens were identified from the National Institute on Deafness and Other Communication Disorders National Temporal Bone Registry and digitized. The c...
3D scalae morphology of the basal turn was normal. Scala tympani (ST) remained isolated for 540 degrees before fusing with scala vestibuli. Mean ST volume reduced below 1 mm 2 after the first 340 degr...
Hallmark features of IP-II cochleae include the following: 1) fusion of the ST and scala vestibuli at a mean of 540 degrees, 2) highly variable and overall reduced SGN quantity compared with normative...
Measurements of the cochlear duct length (CDL) are dependent on the resolution of the imaging dataset....
Previous research has shown highly precise cochlear measurements using 3D-curved multiplanar reconstruction (MPR) and flat-panel volume computed tomography (fpVCT). Thus far, however, there has been n...
fpVCT scans of 10 human petrous bone specimens were performed. CDL was measured using 3D-curved MPR with secondary reconstruction of the fpVCT scans (fpVCTSECO) and increasing resolution from 466 to 9...
Comparison of different imaging resolution settings showed significant differences for CDL measurement in most of the tested groups (p < 0.05), except for the two groups with the highest resolution. I...
3D-curved MPR in fpVCT with a resolution of the imaging dataset of 200 μm or higher revealed the most precise CDL measurement. There was no benefit of using a resolution higher than 200 μm with regard...
The mechanisms underlying the formation of complex structures such as during the outgrowth of the cochlear duct are still poorly understood....
We have analyzed the morphological and molecular changes associated with cochlear development in mouse mutants for the transcription factor Meis2, which show defective coiling of the cochlea. These mo...
Taken together, these data reveal that the loss of Meis2 leads to a phenotype that resembles Shh mutants, suggesting that Meis2 is instrumental for cochlear Shh signaling. The modulation of the same s...
Cochlear duct length (CDL) is subject to significant individual variation. In the context of cochlear implantation, adapting the electrode array length to the CDL is of potential interest, as it has b...
To identify effects of imaging modality and rater background on CDL estimates....
Magnetic resonance imaging (MRI) and flat-panel volume CT (fpVCT) scans of 10 patients (20 cochleae) were analyzed using the OTOPLAN software package (MED-EL, Innsbruck, Austria). Raters were an otorh...
Measurements showed mean CDL...
No effect of rater background on CDL estimates could be identified, suggesting that comparable measurements could be obtained by personnel other than specially trained neurootologists. While imaging m...
