Fig. 2.

Three cases of in vivo application accuracy measurements on postoperative CT scans. The planned trajectories are shown as solid lines. For visualization purposes, the CT bone window setting was used (−200 to 800 HU). A: Coronal and (B) axial reconstructions of the same electrode, showing optimal positioning of the implanted electrode in comparison with the planned trajectory. Target point localization error (TPLE) was 0.83 mm for this electrode. C: Minor deviation in the coronal plane of an orthogonal electrode after insertion in the skull. The TPLE was 2.70 mm. D: Major deformation of the electrode in the coronal plane, with evidence of deviation in the other planes as well, resulting in a TPLE of 9.03 mm. TPLEs were measured in three different planes and calculated using the Euclidean distance