OBJECTIVE: To assess the feasibility and accuracy of predicting electrode insertion depth necessary in cochlear implantations for electric-acoustic stimulation by means of preoperative high-resolution computed tomography (HRCT). DESIGN: Human temporal bone study with evaluation of cochlear dimensions. SETTING: Tertiary care medical center. METHODS: Eight fresh human temporal bones were scanned, and basal cochlear structures were reconstructed and measured. Standard cochlear implantations with a free-fitting array were performed, and the bones then underwent histologic analysis using a technique that allows sectioning of undecalcified bones. After embedding, all bones underwent conventional radiologic analysis with further insertion measurements. Preimplantation HRCT data were compared with radiologic and histologic data. RESULTS: Preimplantation HRCT-based measurements correlated very well with postimplantation radiologic data. A mean failure of 0.3 mm was found. Mean values for the first 360 degrees ranged from 18.8 to 22.0 mm. CONCLUSIONS: Preimplantation HRCT-based prediction of cochlear implant insertion depths is both feasible and accurate. It is especially useful when aiming for hearing preservation, where insertion depths of 360 degrees are necessary.
OBJECTIVE: To assess the feasibility and accuracy of predicting electrode insertion depth necessary in cochlear implantations for electric-acoustic stimulation by means of preoperative high-resolution computed tomography (HRCT). DESIGN:Human temporal bone study with evaluation of cochlear dimensions. SETTING: Tertiary care medical center. METHODS: Eight fresh human temporal bones were scanned, and basal cochlear structures were reconstructed and measured. Standard cochlear implantations with a free-fitting array were performed, and the bones then underwent histologic analysis using a technique that allows sectioning of undecalcified bones. After embedding, all bones underwent conventional radiologic analysis with further insertion measurements. Preimplantation HRCT data were compared with radiologic and histologic data. RESULTS: Preimplantation HRCT-based measurements correlated very well with postimplantation radiologic data. A mean failure of 0.3 mm was found. Mean values for the first 360 degrees ranged from 18.8 to 22.0 mm. CONCLUSIONS: Preimplantation HRCT-based prediction of cochlear implant insertion depths is both feasible and accurate. It is especially useful when aiming for hearing preservation, where insertion depths of 360 degrees are necessary.
Authors: Alejandro Rivas; Ahmet Cakir; Jacob B Hunter; Robert F Labadie; M Geraldine Zuniga; George B Wanna; Benoit M Dawant; Jack H Noble Journal: Otol Neurotol Date: 2017-03 Impact factor: 2.311
Authors: G Jakob Lexow; Daniel Schurzig; Nils-Claudius Gellrich; Thomas Lenarz; Omid Majdani; Thomas S Rau Journal: Int J Comput Assist Radiol Surg Date: 2016-03-19 Impact factor: 2.924
Authors: G Jakob Lexow; Marcel Kluge; Nils-Claudius Gellrich; Thomas Lenarz; Omid Majdani; Thomas S Rau Journal: Eur Arch Otorhinolaryngol Date: 2018-03-12 Impact factor: 2.503