Classification and Analysis of the Errors in Neuronavigation

Abstract

There are many different types of errors in neuronavigation, and the reasons and results of these errors are complex. For a neurosurgeon using the neuronavigation system, it is important to have a clear understanding of when an error may occur, what the magnitude of it is, and how to avoid it or reduce its influence on the final application accuracy. In this article, we classify all the errors into 2 groups according to the working principle of neuronavigation systems. The first group contains the errors caused by the differences between the anatomic structures in the images and that of the real patient, and the second group contains the errors occurring in transforming the position of surgical tools from the patient space to the image space. Each group is further divided into 2 subgroups. We discuss 16 types of errors and classify each of them into one of the subgroups. The classification and analysis of these errors should help neurosurgeons understand the power and limits of neuronavigation systems and use them more properly.

How does adding anatomical landmarks as fiducial points in the point-matching registration of neuronavigation influence registration accuracy?

“…We studied three types of C sm : [3,3,0], [3,3,1] and [3,3,2]. For each type of C sm , we added three different combinations of facial ALs: one AL (nose tip), two ALs (nose tip and nasion) or three ALs (nose tip, nasion and bilateral lateral canthus).…”

“…We studied four types of C sm : [0, 3,2], [1,3,2], [2,3,2] and [3,3,2]. For each type of C sm , we added two combinations of …”

“…The distributions of the TRE csm of SM configuration types [3,3,0], [3,3,1] and [3,3,2] and the TRE cal of the corresponding fiducial configurations obtained by adding different combinations of facial ALs are illustrated in Figure 2. Regardless of the presence of SMs in the Anterior Region, the TRE cal of the configurations with additional facial ALs always falls into a lower and narrower range than the TRE csm of the corresponding configuration using only SMs.…”

“…The process of establishing spatial correspondence is called registration, and it is both the basis of neuronavigation and one of the major sources of errors. [1,2] Point-matching and surface-matching are two types of methods that are used for registration of neuronavigation, and the first kind, point-matching, is more widely used clinically. [3] In point-matching, the surgeons first select a set of fiducial points on the images and then select a set of spatially corresponding points on the patient's head.…”

Optimal number and distribution of points selected on the vertebra for surface matching in CT-based spinal navigation

“…Most CT-based spinal navigation systems use point matching followed by a surface-matching approach to register the two spaces [8][9][10][11][12][13]. Many factors contribute to the error of this kind of spatial registration [14], with the surgeon's decision regarding the number and distribution of points to be selected in the patient space playing an important role.…”