Augmented reality for endoscopic sinus surgery with surgical navigation: a cadaver study

Abstract

Introduction Augmented reality (AR) fuses computer-generated images of preoperative imaging data with real-time views of the surgical field. Scopis Hybrid Navigation (Scopis, GmbH, Berlin, Germany) is a surgical navigation system with AR capabilities for endoscopic sinus surgery (ESS). Methods Pre-dissection planning was performed with Scopis Hybrid Navigation software followed by ESS dissection on 2 human specimens using conventional ESS instruments. Results Pre-dissection planning included creating models of relevant frontal recess structures and the frontal sinus outflow pathway on orthogonal CT images. Positions of the optic nerve and internal carotid artery were marked on the CT images. Models and annotations were displayed as an overlay on the endoscopic images during the dissection, which was performed with electromagnetic surgical navigation. The accuracy of the AR images relative to underlying anatomy was better than 1.5 mm. The software's trajectory targeting tool was used to guide instrument placement along the frontal sinus outflow pathway. AR imaging of the optic nerve and internal carotid artery served to mark the positions of these structures during the dissection. Conclusions Surgical navigation with AR was easily deployed in this cadaveric model of ESS. This technology builds upon the positive impact of surgical navigation during ESS, particularly during frontal recess surgery. Instrument tracking with this technology facilitates identifying and cannulation of the frontal sinus outflow pathway without dissection of the frontal recess anatomy. AR can also highlight “anti-targets” (i.e., structures to be avoided), such as the optic nerve and internal carotid artery, and thus reduce surgical complications and morbidity.

Initial experience with image‐guided surgical navigation in transoral surgery

“…However, this form of tri-planar image presentation was more difficult to follow given the additional soft tissue deformation of the upper aerodigestive tract as well as the presence of the laryngoscope. The use of augmented or virtual reality, in which imaging information is incorporated within the real-time surgical view, is an area of active research in multiple surgical disciplines 21,36,37 including otolaryngology 30,38,39 . Segmentation of the areas of interest – such as the tumor, anatomic landmarks, and vascular structures – and presenting this imaging information as an overlay on the endoscopic or microscopic view would be more intuitive and allow the surgeon to maintain focus on the surgical field without diverting attention to the navigation imaging.…”

Cirugía endoscópica nasosinusal y de base de cráneo asistida por navegación

“…En cuanto a sus ventajas la navegación permitiría realizar una planificación quirúrgica preoperatoria, ahorrar tiempo quirúrgico, una exploración más completa en un área potencialmente peligrosa manteniendo la indemnidad de estructuras nobles, favorecer la formación de futuros cirujanos y acortar su curva de aprendizaje, además de ser beneficiosa en la confirmación de la indemnidad quirúrgica de estructuras nobles en cirugía sinusal, especialmente en cirujanos menos experimentados 10 . Se espera que el error objetivo razonable esté en el rango de 1,5 a 2,0 mm con esta herramienta, utilizándose navegación con realidad aumentada se ha estimado un error de 1,5 mm o menos 11 , en un estudio reciente el uso de navegación virtual 3D no demostró superioridad en comparación a una guía de imagen triplana convencional 12 . Se ha estimado que en nuestro centro el registro de error no supera 1 mm.…”

Training in ENT; a comprehensive review of existing evidence

“…IGS provides a way for surgeons to track, during surgery, their instruments' tips relative to the preoperative imaging data (54) (sinus CT scan for example). Recently, IGS systems are being combined with AR, which fuses computer-generated images of preoperative imaging data with real-time views of the surgical field (57,58) . This means that if the pathway to the frontal sinus is annotated on the preoperative CT images, the surgeon will visualize that pathway as a projection displayed over the live endoscopic images.…”

“…Examples of these IGS with AR commercially available are from Scopis (Scopis-TGS) and Storz (Storz NAV1), with the planning software of the former being based on the building-blocks concept proposed by Wormald (57) .…”