Christoph Rathgeb1, Marco Demattè2,3, Abraam Yacoub2,4, Lukas Anschuetz2, Franca Wagner5, Georgios Mantokoudis2, Marco Caversaccio1,2, Wilhelm Wimmer1,2. 1. Hearing Research Laboratory, Artificial Organs Center for Biomedical Engineering Research. 2. Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern. 3. Department of Otorhinolaryngology, Head & Neck Surgery, Head and Neck and Sensory Organs Department, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy. 4. Department of Otorhinolaryngology, Faculty of Medicine, Ain Shams University, Cairo, Egypt. 5. Department of Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital and University of Bern, Bern, Switzerland.
Abstract
OBJECTIVE: Evaluation of the accuracy and clinical applicability of a single measure cochlear implant angular insertion depth prediction method. BACKGROUND: Cochlear implantation outcomes still vary extensively between patients. One of the possible reasons could be variability in intracochlear electrode array placement. For this reason, single measure methods were suggested to preoperatively predict angular insertion depths. Based on a previously performed accuracy study in human temporal bones, we were interested in determining the extent to which the method could be applied in a clinical setting. METHODS: A retrospective analysis was performed on pre- and postoperative radiographic images of 50 cochlear implant recipients. Preoperatively predicted angular insertion depths were compared with angular insertion depths measured on postoperative ground truth. The theoretical prediction error was computed under the assumption that all achieved insertions were matching the preoperatively assumed linear insertion depth. More importantly, the clinical prediction error was assessed using two different software tools performed by three experienced surgeons. RESULTS: Using the proposed method we found a theoretical prediction error of 5 degrees (SD = 41 degrees). The clinical prediction error including the cases with extracochlear electrodes was 70 degrees (SD = 96 degrees). CONCLUSIONS: The presented angular insertion depth prediction method is a first practical approach to support the preoperative selection of cochlear implant electrode arrays. However, the presented procedure is limited in that it is unable to predict the occurrence of insertion results with extracochlear electrodes and requires user training.
OBJECTIVE: Evaluation of the accuracy and clinical applicability of a single measure cochlear implant angular insertion depth prediction method. BACKGROUND: Cochlear implantation outcomes still vary extensively between patients. One of the possible reasons could be variability in intracochlear electrode array placement. For this reason, single measure methods were suggested to preoperatively predict angular insertion depths. Based on a previously performed accuracy study in human temporal bones, we were interested in determining the extent to which the method could be applied in a clinical setting. METHODS: A retrospective analysis was performed on pre- and postoperative radiographic images of 50 cochlear implant recipients. Preoperatively predicted angular insertion depths were compared with angular insertion depths measured on postoperative ground truth. The theoretical prediction error was computed under the assumption that all achieved insertions were matching the preoperatively assumed linear insertion depth. More importantly, the clinical prediction error was assessed using two different software tools performed by three experienced surgeons. RESULTS: Using the proposed method we found a theoretical prediction error of 5 degrees (SD = 41 degrees). The clinical prediction error including the cases with extracochlear electrodes was 70 degrees (SD = 96 degrees). CONCLUSIONS: The presented angular insertion depth prediction method is a first practical approach to support the preoperative selection of cochlear implant electrode arrays. However, the presented procedure is limited in that it is unable to predict the occurrence of insertion results with extracochlear electrodes and requires user training.
Authors: Franz-Tassilo Müller-Graff; Lukas Ilgen; Philipp Schendzielorz; Johannes Voelker; Johannes Taeger; Anja Kurz; Rudolf Hagen; Tilmann Neun; Kristen Rak Journal: Eur Arch Otorhinolaryngol Date: 2021-06-08 Impact factor: 3.236