Image-guided endoscopic spine surgery - Part II: Clinical applications

Study Design. Endoscopic spinal procedures were performed under computed-tomography-based, image-guided assistance. Objective. To assess the clinical feasibility of applying a methodology that allows image-guided assistance in endoscopic spinal surgery. Summary of Background Data. Endoscopic spinal procedures have become a part of the minimal invasive approaches to the spine. The main disadvantage of these techniques is the long learning curve and the lack of peroperative monitoring. Fluoroscopy does have disadvantages, such as positioning during surgery and the risk for radiation exposure. Fluoroscopy-based navigation has many advantages, however it is still based on preselected fluoroscopic images. There is no method that allows computed-tomography-based navigation in endoscopic conditions. Methods. Two patients have been operated on using endoscopic approaches assisted by computed-tomography-based navigational system. One had a thoracoscopic approach for median calcified disc herniation and another one had an endoscopic posterior approach for resection of a sacro-iliac osteophyte. For each patient, a frame of reference had been placed percutaneously and scanned. The computed tomography images were registered to the anatomy using the geometry of the frame as fiducials. Navigation through endoscopic approaches was possible in both cases. Results. In both cases navigation was reliable and a helpful monitoring to achieve the surgical goals through endoscopic approaches. Conclusions. There are some factors that make endoscopic spine surgery a difficult start. Image-guided spine surgery is technically feasible and clinically applicable in endoscopic approaches.