A novel view of computed tomography images similar to the visual field of otologic surgeons

Abstract

Objectives: In preparation for endoscopic sinus surgery (ESS), the most important computed tomography (CT) image for otolaryngologists is the coronal plane image because it has a viewpoint similar to that of the surgical visual field. Contrastingly, otologic surgeons refer to axial and coronal plane images before ear surgery and must imagine the anatomical structure of the temporal bone by reconstructing threedimensional (3D) images in their minds. We propose a "surgical position view (SPV) image," a novel viewpoint of CT images that enables otologic surgeons to see a perspective similar to the surgical visual field.Method: Sagittal plane CT images of the temporal bone were created from axial plane images with multi-planar reconstruction (MPR). Then, the SPV image was obtained by rotating it 90 to the supine position. The entire process can be performed anywhere in the hospital within 1 minute using the electronic medical record computer's image viewer.Results: SPV images show anatomical structures of the temporal bone, external ear canal, mastoid cavity, sigmoid vein, facial nerve, ossicles, and cochlea, in a similar view to the actual ear surgery. Soft tissue such as cholesteatoma is depicted in the same concentration as the normal CT image. Conclusion:The SPV image enables an otologic surgeon to see the temporal bone CT image from the actual ear surgery viewpoint simply and quickly. It helps to visualize the 3D anatomical structure of the temporal bone and can be useful for ear surgery planning.