A Simulation-Free Replacement Solution for Radiation Therapy Immobilization Devices Using Computer Numerical Control (CNC) -Milled Polystyrene Molds.

Purpose: In radiation therapy (RT), if an immobilization device is lost or damaged, the patient may need to be brought back for resimulation, device fabrication, and treatment planning, causing additional imaging radiation exposure, inconvenience, cost, and delay. We describe a simulation-free method for replacing lost or damaged RT immobilization devices.

Methods And Materials: Replacement immobilization devices were fabricated using existing simulation scans as design templates by computer numerical control (CNC) milling of molds made from extruded polystyrene (XPS).

A Prospective Study on Deep Inspiration Breath Hold Thoracic Radiation Therapy Guided by Bronchoscopically Implanted Electromagnetic Transponders.

Background: Electromagnetic transponders bronchoscopically implanted near the tumor can be used to monitor deep inspiration breath hold (DIBH) for thoracic radiation therapy (RT). The feasibility and safety of this approach require further study.

Methods: We enrolled patients with primary lung cancer or lung metastases.

Failure mode and effect analysis for linear accelerator-based paraspinal stereotactic body radiotherapy.

Introduction: Paraspinal stereotactic body radiotherapy (SBRT) involves risks of severe complications. We evaluated the safety of the paraspinal SBRT program in a large academic hospital by applying failure modes and effects analysis.

Methods: The analysis was conducted by a multidisciplinary committee (two therapists, one dosimetrist, four physicists, and two radiation oncologists).

Risk Management of Clinical Reference Dosimetry of a Large Hospital Network Using Statistical Process Control.

Managing TG-51 reference dosimetry in a large hospital network can be a challenging task. The objectives of this study are to investigate the effectiveness of using Statistical Process Control (SPC) to manage TG-51 workflow in such a network. All the sites in the network performed the annual reference dosimetry in water according to TG-51.

An investigation of using log-file analysis for automated patient-specific quality assurance in MRgRT.

Objective: Adaptive radiation therapy (ART) is an integral part of MR-guided RT (MRgRT), requiring a new RT plan for each treatment fraction and resulting in a significant increase in patient-specific quality assurance (PSQA). This study investigates the possibility of using treatment log-file for automated PSQA.

Method: All treatment plans were delivered in 1.

Commissioning of optical surface imaging systems for cranial frameless stereotactic radiosurgery.

Purpose: This study aimed to evaluate and compare different system calibration methods from a large cohort of systems to establish a commissioning procedure for surface-guided frameless cranial stereotactic radiosurgery (SRS) with intrafractional motion monitoring and gating. Using optical surface imaging (OSI) to guide non-coplanar SRS treatments, the determination of OSI couch-angle dependency, baseline drift, and gated-delivered-dose equivalency are essential.

Methods: Eleven trained physicists evaluated 17 OSI systems at nine clinical centers within our institution.

A novel quality assurance procedure for trajectory log validation using phantom-less real-time latency corrected EPID images.

The use of trajectory log files for routine patient quality assurance is gaining acceptance. Such use requires the validation of the trajectory log itself. However, the accurate localization of a multileaf collimator (MLC) leaf while it is in motion remains a challenging task.

Commissioning and quality assurance for VMAT delivery systems: An efficient time-resolved system using real-time EPID imaging.

Purpose: An ideal commissioning and quality assurance (QA) program for Volumetric Modulated Arc Therapy (VMAT) delivery systems should assess the performance of each individual dynamic component as a function of gantry angle. Procedures within such a program should also be time-efficient, independent of the delivery system and be sensitive to all types of errors. The purpose of this work is to develop a system for automated time-resolved commissioning and QA of VMAT control systems which meets these criteria.

No association between excessive wound complications and preoperative high-dose, hypofractionated, image-guided radiation therapy for spine metastasis.

Object: Radiation therapy is known to impair wound healing. Higher dose per fraction is believed to increase this risk. This study sought to quantify rates of wound complication in patients receiving preoperative conventionally fractionated radiotherapy (XRT) or high-dose hypofractionated image-guided radiation therapy (IGRT) for spinal metastasis, and to identify predictors of wound complication.

Accurate positioning for head and neck cancer patients using 2D and 3D image guidance.

Our goal is to determine an optimized image-guided setup by comparing setup errors determined by two-dimensional (2D) and three-dimensional (3D) image guidance for head and neck cancer (HNC) patients immobilized by customized thermoplastic masks. Nine patients received weekly imaging sessions, for a total of 54, throughout treatment. Patients were first set up by matching lasers to surface marks (initial) and then translationally corrected using manual registration of orthogonal kilovoltage (kV) radiographs with DRRs (2D-2D) on bony anatomy.

Local disease control after decompressive surgery and adjuvant high-dose single-fraction radiosurgery for spine metastases.

OBJECT Adjuvant radiation following epidural spinal cord decompression for tumor is a powerful tool used to achieve local disease control and preserve neurological function. To the authors' knowledge, only 1 published report addresses adjuvant stereotactic radiosurgery after this procedure, but that study used significantly lower doses than are currently prescribed. The authors review their experience using high-dose single-fraction radiosurgery as a postoperative adjuvant following surgical decompression and instrumentation to assess long-term local tumor control, morbidity, and survival.