Precision and accuracy of stereotactic targeting in patients undergoing repeat stereotactic surgery

Background/Aims: Accurate and precise stereotactic targeting is crucial in obtaining the best outcome for patients undergoing functional neurosurgical procedures. Methods: We calculated the precision and accuracy of stereotactic targeting in 20 consecutive patients who underwent repeat stereotactic surgery from January 2001 to December 2007 at one institution. Two sets of target coordinates were calculated for each patient undergoing repeat surgery from their magnetic resonance images and using Stealth Station and Framelink software. The 1st target coordinate was the initial stereotactic lesion or known functional electrode contact and the 2nd was the computer-calculated coordinate of the selected functional target (ventrointermediate, globus pallidus internus, or subthalamic nucleus ) for the repeat surgery. Results: All patients had a good functional outcome following the initial surgery. Mean differences between coordinates (for all stereotactic targets combined) were 1.35, 1.18 and 1.28 mm for X, Y and Z, respectively. The absolute difference between target points was 2.77 mm. Conclusion: This demonstrates a high level of precision and accuracy with contemporary frame-based neuronavigation and stereotactic techniques. Similar data can be easily collected and analyzed for auditing purposes at any neurosurgical center to ensure optimal outcome for patients.