Use of MRI fusion for CT based intracranial stereotactic radiosurgery

The aim of this study is to evaluate the reliability of MRI fusion when determining intracranial target volume when performing CT based intracranial stereotactic radiosurgery. Patients treated with CT based intracranial stereotactic radiosurgery with various diagnosis are included in the study. All patients were immobilized using stereotactic thermoplastic masks prior to simulation. The planning CT was obtained both with and without iv contrast with 1mm slice thickness. The images obtained were then fused with 3D, T1 weighted MR images with contrast by two different platforms (Eclipse 10.0, Velocity 3.0 rigid and Velocity 3.0 deformable).