Figure 5From: Study on the clinical application of pulsed DC magnetic technology for tracking of intraoperative head motion during frameless stereotaxyThe application accuracy was monitored intraoperatively using as a reference point a 1 mm burr hole (b) drilled into the exposed bone margin (a) directly after craniotomy. The Cartesian coordinates of this reference point were used to calculate the intraoperative Position Error (PE = (Δsagittal 2 + Δcoronal 2 + Δaxial 2)1/2) in mm.Back to article page