Image-Guided Treatment of Fractionated Stereotactic Radiotherapy Patients: A Quantitative Analysis of Pre- and Post-Treatment Orthogonal kV Images of Patients Immobilized with Thermoplastic Masks.

Objectives: To measure setup and intrafraction variability for intracranial targets during treatment of patients immobilized with a Brainlab, Inc. thermoplastic head mask using ExacTrac© imaging on the treatment unit.

Patients And Methods: Between November 2007 and June 2008, 12 patients were treated with cranial fractionated stereotactic radiation therapy for 25-28 fractions.