A collision prediction framework for noncoplanar radiotherapy planning and delivery.

Purpose: Noncoplanar radiotherapy can provide significant dosimetric benefits. However, clinical implementation of such techniques is not fully realized, partially due to the absence of a collision prediction tool integrated into the clinical workflow. In this work, the feasibility of developing a collision prediction system (CPS) suitable for integration into clinical practice has been investigated.

Quality assurance tests for the Gamma Knife Icon™ image guidance system.

Introduction: The Gamma Knife Icon™ comes with an image guidance system for tracking patient motion and correcting for inter- and intrafractional shifts, mainly used with frameless thermoplastic immobilization. The system consists of a cone-beam CT (CBCT) and a couch-mounted infrared camera (IFMM). We report our quality assurance program for Icon's image guidance system.

An Evaluation of the ICON Mask Fixation: Curing Characteristics of the Thermoplastic Fixation and Implications for Patient Workflow.

Background: Thermoplastic mask immobilization is used to perform hypo-fractionated treatments with the Gamma Knife ICON®.

Materials And Methods: We evaluated the curing characteristics of the ICON® Nanor mask using force sensing resistors coupled with a data logging tool designed by us.

Results: For patients being treated with masks made the same day as the treatment, often in the same sitting with no removal and replacement of the patient from the treatment cradle, based on the curves 80% of the force of fixation is reached at 30 minutes.

Improved dose homogeneity using electronic compensation technique for total body irradiation.

In total body irradiation (TBI) utilizing large parallel-opposed fields, the manual placement of lead compensators has conventionally been used to compensate for the varying thickness throughout the body. The goal of this study is to pursue utilizing the modern electronic compensation (E-comp) technique to more accurately deliver dose to TBI patients. Bilateral parallel-opposed TBI treatment plans were created using E-comp for 15 patients for whom CT data had been previously acquired.

Impact of the Number of Metastatic Tumors Treated by Stereotactic Radiosurgery on the Dose to Normal Brain: Implications for Brain Protection.

Purpose/objectives: The purpose of this study was to evaluate the effect of the number of brain lesions for which stereotactic radiosurgery (SRS) was performed on the dose volume relationships in normal brain.

Materials And Methods: Brain tissue was segmented using the patient's pre-SRS MRI. For each plan, the following data points were recorded: total brain volume, number of lesions treated, volume of brain receiving 8 Gy (V8), V10, V12, and V15.