The role of imaging and navigation for natural orifice translumenal endoscopic surgery.

ABSTRACT

BACKGROUND AND PURPOSE: One of the next frontiers of minimally invasive surgery is natural orifice translumenal endoscopic surgery (NOTES). This article focuses on the perspectives and limitations of imaging and navigation in NOTES soft-tissue surgery. MATERIALS AND METHODS: Based on our in-vitro and in-vivo studies, with the applicability of different systems for image-guided soft-tissue endoscopic surgery, early experience with NOTES, and long-term experience with advanced endoluminal, laparoscopic robot-assisted endoscopic surgery, we performed a review of the literature. The aim was a critical analysis of the current role of imaging during NOTES. RESULTS: There are several steps/problems with NOTES that might be significantly alleviated by use of imaging and soft-tissue navigation. One has to distinguish between preoperative planning and intraoperative imaging or navigation. NOTES represents a hybrid technique of laparoscopy and endoscopy with similar limitations in perception and two-dimensional imaging; however, the use of flexible instruments increases the complexity with respect to the spatial orientation. This applies not only for the surgeon, but also for tracking devices for surgical navigation systems. Unlike optical navigation systems, electromagnetic and endoscopic (inside-out) tracking devices might be best suited to NOTES. CONCLUSION: The safe realization and standardization of NOTES represents a real challenge that necessitates close and effective interdisciplinary collaboration of surgeon, technicians, informatics, and endoscopic and applied industries. Image-guided soft-tissue navigation may be very helpful to minimize the hazards of the technically challenging procedure.