Image-guided spine surgery: state of the art and future directions

Abstract

Navigation technology is a widely available tool in spine surgery and has become a part of clinical routine in many centers. The issue of where and when navigation technology should be used is still an issue of debate. It is the aim of this study to give an overview on the current knowledge concerning the technical capabilities of image-guided approaches and to discuss possible future directions of research and implementation of this technique. Based on a Medline search total of 1,462 publications published until October 2008 were retrieved. The abstracts were scanned manually for relevance to the topics of navigated spine surgery in the cervical spine, the thoracic spine, the lumbar spine, as well as ventral spine surgery, radiation exposure, tumor surgery and cost-effectivity in navigated spine surgery. Papers not contributing to these subjects were deleted resulting in 276 papers that were included in the analysis. Image-guided approaches have been investigated and partially implemented into clinical routine in virtually any field of spine surgery. However, the data available is mostly limited to small clinical series, case reports or retrospective studies. Only two RCTs and one metaanalysis have been retrieved. Concerning the most popular application of image-guided approaches, pedicle screw insertion, the evidence of clinical benefit in the most critical areas, e.g. the thoracic spine, is still lacking. In many other areas of spine surgery, e.g. ventral spine surgery or tumor surgery, image-guided approaches are still in an experimental stage. The technical development of image-guided techniques has reached a high level as the accuracies that can be achieved technically meet the anatomical demands. However, there is evidence that the interaction between the surgeon ('human factor') and the navigation system is a source of inaccuracy. It is concluded that more effort needs to be spend to understand this interaction.

Minimally invasive versus open transforaminal lumbar interbody fusion: a meta-analysis based on the current evidence

“…Their study revealed that navigated MI-TLIF significantly reduced intraoperative radiation exposure when compared with open-TLIF using standard fluoroscopy [23]. Moreover, it has been reported that navigation could also reduce fluoroscopic time during the placement of pedicle screws [24]. In the future, navigation may be one of the ways to solve the problems of excessive X-ray exposure of the surgeons.…”

Accuracy of lower cervical pedicle screw placement with assistance of distinct navigation systems: a human cadaveric study

“…Experimental studies showed that there was no significant difference in the accuracy between traditional X-ray fluoroscopy and fluoroscopy-based navigation, indicating that the accuracy of navigation system itself was acceptable and close to the accuracy of traditional fluoroscopy. Furthermore, it might reduce the operation time and the radiation injuries to patients, nurses, and surgeons [7,12]. However, some limitations of fluoroscopy images should be taken into account, such as the requirement of clinical experience for the interpretation of the spinal images, and the difficulties to decide accurate angles and entry point in cervical pedicle screw placement.…”

“…Therefore, improvement to the accuracy of the cervical pedicle screw placement is the key to reduce the complications and adverse effects [6]. The computer-assisted navigation system has been gradually applied into spine surgeries [7]. However, the natural value of the navigation system in the spinal surgical procedure was questioned [8].…”

Pedicle screw insertion accuracy with different assisted methods: a systematic review and meta-analysis of comparative studies

“…The radiation exposure of the patients mainly depends on the CT protocol [59][60][61]. By analyzing the radiation of three different CT protocols-based navigation system, Slomczykowski et al [59] noted that when CTNav was to be used, the spiral mode of CT scanning was recommended.…”