A Web-Based Automated Image Processing Research Platform for Cochlear Implantation-Related Studies

Abstract

The robust delineation of the cochlea and its inner structures combined with the detection of the electrode of a cochlear implant within these structures is essential for envisaging a safer, more individualized, routine image-guided cochlear implant therapy. We present Nautilus—a web-based research platform for automated pre- and post-implantation cochlear analysis. Nautilus delineates cochlear structures from pre-operative clinical CT images by combining deep learning and Bayesian inference approaches. It enables the extraction of electrode locations from a post-operative CT image using convolutional neural networks and geometrical inference. By fusing pre- and post-operative images, Nautilus is able to provide a set of personalized pre- and post-operative metrics that can serve the exploration of clinically relevant questions in cochlear implantation therapy. In addition, Nautilus embeds a self-assessment module providing a confidence rating on the outputs of its pipeline. We present a detailed accuracy and robustness analyses of the tool on a carefully designed dataset. The results of these analyses provide legitimate grounds for envisaging the implementation of image-guided cochlear implant practices into routine clinical workflows.

Anatomical Variations of the Human Cochlea Using an Image Analysis Tool

“…Recent advances in automated analysis tools such as CoreSlicer 2.0 (CoreSlicer, Montreal, QC, Canada), Innersight 3D (Innersight Labs, London, UK), Arterys (Arterys Inc., Redwood Shores, CA, USA), etc., have made it possible to conduct larger studies with more robust and reliable results, as demonstrated in a recent study on cardiac anatomy which showed the feasibility and reliability of using automated analysis tools for population studies [ 43 ]; thus, similar approaches can be applied to cochlear anatomy. This study analyzed a large number of clinical temporal bone CT images using Nautilus (v20220801; Oticon Medical [ 31 ]) to determine cochlear morphology and characteristics, making it more efficient and robust than manual measurements. Nautilus is a web-based image analysis tool that supports the automatic analysis of pre-operative surgical planning and post-operative assessment for cochlear implant procedures; additionally, ithas the potential to influence the intraoperative workflow in an augmented reality setup and to control insertion forces and trajectories.…”

“…Although only the cochlear center landmark was required for further processing, using a three landmark C-MARL approach ensured better detection of the landmark [ 33 ]. CT image-detected cochlear center landmark coordinates, cochlear side and operative status for each CT image were compiled and uploaded to Nautilus (v20220801; Oticon Medical, Vallauris, France)—a web-based cochlear image analysis tool [ 31 ].…”

“…Recent studies relating cochlear morphology to CI electrode insertion focused on the establishment of normative datasets and reliable cochlear size measures [ 28 ], quantification of internal cochlear dimensions with high precision [ 27 ], evaluation of electrode mechanical properties in relation to induced cochlear trauma [ 29 ] or the establishment of a mathematical model that describes the shape of the cochlea [ 30 ]. In this study, variability and correlation of cochlear parameters, extracted via 3D reconstruction by the Oticon Medical Nautilus software [ 31 ], are investigated in a large set of 1099 cochleae. Additionally, intra-patient, inter-patient and inter-sex similarities are also analyzed.…”

Electrical Field Interactions during Adjacent Electrode Stimulations: eABR Evaluation in Cochlear Implant Users

“…However, this observation should be relativized by the fact that for the current experiment, we used a wide range of measure-configurations and stimulation intensities in order to obtain a full-picture of the approach, but the MIC could be obtained using much fewer stimulation combinations, thereby effectively reducing the recording time to less than an hour and increasing the clinical relevance of the approach. Moreover, eABRs could be selectively used only on a subset of electrodes which would be ‘suspected’ of creating high interactions, for example, after analysis of post-images identifying ill-placed electrodes within the cochlea [ 46 , 47 , 48 ]. Further work could aim at directly comparing different electrophysiological approaches for the characterization of channel interactions in a systematic way.…”

The Effects of Multi-Mode Monophasic Stimulation with Capacitive Discharge on the Facial Nerve Stimulation Reduction in Young Children with Cochlear Implants: Intraoperative Recordings

“…The CT-scans were acquired at a resolution of 0.3 × 0.3 × 0.4 mm 3 . CT image reconstruction was performed using a web-based research platform Nautilus [ 14 ], which combines a convolutional neural network (CNN) approach with Bayesian joint appearance and shape inference for segmenting the cochlea and determining the trajectory of the electrode arrays. The angular positioning of the electrodes was determined automatically using Nautilus which extracts electrode position from postoperative CT-scan using a CNN approach and registers it with preoperative CT-scan for determining the electrode position with respect to the cochlear segmentation.…”