Alignment correction algorithm for transformation of stereotactic anterior commissure/posterior commissure-based coordinates into frame coordinates for image-guided functional neurosurgery

The goal was to describe an alignment correction algorithm for the transformation of stereotactic atlas-derived anterior commissure/posterior commissure-based coordinates into frame coordinates for image-guided functional stereotactic neurosurgery. The algorithm was developed for the calculation of targets that are referenced to the intercommissural line. It corrects for deviations of the axis of the intercommissural line in relation to the stereotactic frame (x, y, and z coordinates). The algorithm is easily implemented on a personal computer with a spreadsheet program. The calculation is fast and effective.