A Gaussian approach for the calculation of the accuracy of stereotactic frame systems

Abstract

Stereotactic frame systems are widely used in neurosurgery. The accuracy of frame devices is considered as a gold standard to which the accuracy of new frameless stereotactic navigation systems is compared. The purpose of this study is to develop a general approach for the prediction of the application accuracy of stereotactic systems. The approach will be applied to the frame-based biopsy performed with three frame devices: Leksell G, Cosman-Roberts-Wells ͑CRW͒, and Brown-Roberts-Wells ͑BRW͒. A work-flow analysis will be carried out demonstrating that the accuracy relevant for a clinical application comprises several error sources including imaging, target and entry point selection, image to frame coordinates registration, and the setting of mechanical parameters of the frame. These error sources will be postulated to obey a Gaussian distribution probability density. The linear, i.e., Gaussian, error propagation, will be used to link all error contributions thus to calculate the cumulative accuracy of the frame used in the application. Although the Gaussian approach is an approximation, it allows for an analytical treatment of the accuracy. Both the accuracy at the target point and the accuracy of the probe needle guidance along the planned trajectory have been investigated. Of great significance is the relationship found between accuracy, pixel dimension, and image slice thickness, the latter being the dominant factor for slices of more than 1.5 mm thickness, yielding inaccuracies larger than 1.5 mm. For target points the predictions for the application accuracy have been compared to the results of measurements, showing good agreement with the experimental data. © 1999 American Association of Physicists in Medicine. ͓S0094-2405͑99͒01803-9͔

Comparative Study of Robot-Assisted versus Conventional Frame-Based Deep Brain Stimulation Stereotactic Neurosurgery

“…According to the literature, current stereotactic procedures are, however, associated with errors in the order of 1–2 mm [20, 25, 26]. Lead displacement with lateral deviations ≥1.40 mm during subthalamic nucleus DBS were shown to be likely associated with unfavorable spread of electrical current into adjacent eloquent areas leading to extensive stimulation-induced side effects [27].…”

System for robotically assisted percutaneous procedures with computed tomography guidance

“…These fiducial systems, like the BRW or Leksell frames, have been used in similar circumstances for decades, and their accuracies and error characteristics are well documented. [15][16][17][18] Susil et al 34 also proved that the Z-shaped fiducial motifs of conventional stereotactic frames demonstrate favorable error characteristics, accuracy, and reliability in a large angular range. In our design (Fig.…”

“…[11][12][13][14][15][16][17][18] Early experiences with CT-guided robots were also associated with invasive head frames. 19 -21,46 For procedures that require access to the abdomen or spine, full-body stereotactic frames were developed.…”

Neuronavigation accuracy dependence on CT and MR imaging parameters: a phantom-based study

“…Finally, the chosen experimental approach allows us to separately evaluate the imaging contribution and the global accuracy, while in the literature, with few exceptions (Kaus et al 1997, Torresin et al 1999, only the latter one is normally investigated (Dorward et al 1999, Vannier and Haller 1999, Zylka et al 1999, Maciunas et al 1994, Willems et al 2001. …”

“…The registration process then, which translates data from the patient reference system to the imaging one, besides presenting an intrinsic inaccuracy (software algorithm), is related to the input data quality. In fact, it uses images and patient coordinates acquired with a pointer device, affected by a mechanical error (Zylka et al 1999, Maciunas et al 1994. Nowadays, the mechanical accuracy of many hand-held localization devices is submillimetric, making it comparable to the mechanical accuracy of frame-based localization systems (Kaus et al 1997).…”