Panorama imaging for image-to-physical registration of narrow drill holes inside spongy bones
Creators: name: Bergmeier, Jan
name: Fast, Jacob Friedemann
name: Ortmaier, Tobias
name: Kahrs, Lüder Alexander
Publisher: name: Bellingham, Wash. : SPIE
Year: 2017
Subjects: subject: Cochlear implantation
subject: Endoscopic procedures
subject: Image-guided surgery
subject: Intraoperative imaging
subject: Bone
subject: Cochlear implants
subject: Computerized tomography
subject: Drills
subject: Endoscopy
subject: Errors
subject: Image processing
subject: Image registration
subject: Lenses
subject: Optical data processing
subject: Optical systems
subject: Robotics
subject: Rock drills
subject: Surgery
subject: Tomography
subject: Volumetric analysis
subject: Computed tomography images
subject: Cone-beam computed tomography
subject: Image guided surgery
subject: Image-processing software
subject: Image-to-image registration
subject: Intra-operative imaging
subject: Target registration errors
subject: Medical imaging
subject: Konferenzschrift
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau

description: Image-to-physical registration based on volumetric data like computed tomography on the one side and intraoperative endoscopic images on the other side is an important method for various surgical applications. In this contribution, we present methods to generate panoramic views from endoscopic recordings for image-to-physical registration of narrow drill holes inside spongy bone. One core application is the registration of drill poses inside the mastoid during minimally invasive cochlear implantations. Besides the development of image processing software for registration, investigations are performed on a miniaturized optical system, achieving 360° radial imaging with one shot by extending a conventional, small, rigid, rod lens endoscope. A reflective cone geometry is used to deflect radially incoming light rays into the endoscope optics. Therefore, a cone mirror is mounted in front of a conventional 0° endoscope. Furthermore, panoramic images of inner drill hole surfaces in artificial bone material are created. Prior to drilling, cone beam computed tomography data is acquired from this artificial bone and simulated endoscopic views are generated from this data. A qualitative and quantitative image comparison of resulting views in terms of image-to-image registration is performed. First results show that downsizing of panoramic optics to a diameter of 3mm is possible. Conventional rigid rod lens endoscopes can be extended to produce suitable panoramic one-shot image data. Using unrolling and stitching methods, images of the inner drill hole surface similar to computed tomography image data of the same surface were created. Registration is performed on ten perturbations of the search space and results in target registration errors of (0:487 ± 0:438)mm at the entry point and (0:957 ± 0:948)mm at the exit as well as an angular error of (1:763 ± 1:536)°. The results show suitability of this image data for image-to-image registration. Analysis of the error components in different directions reveals a strong influence of the pattern structure, meaning higher diversity results into smaller errors. © 2017 SPIE.