PURPOSE A software program (MU-EPID) has been developed to perform patient specific IMRT pre-treatment QA verification using an electronic portal imaging device. METHODS The software converts measured images of intensity modulated beams delivered to an EPID, into fluence maps that can be imported in the treatment planning system. The dose can then be calculated in the patient anatomy and comp...

Volumetric-modulated arc radiotherapy (VMAT) is an iteration of intensity-modulated radiotherapy (IMRT), both of which deliver highly conformal dose distributions. Studies have shown the superiority of VMAT and IMRT in comparison with 3-dimensional conformal radiotherapy (3D-CRT) in planning target volume (PTV) coverage and organs-at-risk (OARs) sparing. This is the first study examining the be...

PURPOSE To assess the impact of two multileaf collimator (MLC) systems (2.5 and 5 mm leaf widths) on three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, and dynamic conformal arc techniques for stereotactic body radiation therapy (SBRT) of liver and lung lesions. METHODS Twenty-nine SBRT plans of primary liver (n=11) and lung (n=18) tumors were the basis of this study....

Published data suggests that wedge resection for stage I non-small cell lung cancer (NSCLC) is associated with improved overall survival compared to stereotactic body radiation therapy. We report CyberKnife outcomes for high-risk surgical patients with biopsy-proven stage I NSCLC. PET/CT imaging was completed for staging. Three-to-five gold fiducial markers were implanted in or near tumors to s...

Total skin electron irradiation (TSEI) has been used as a treatment for mycosis fungoides. Our center has implemented a modified Stanford technique with six pairs of 6 MeV adjacent electron beams, incident perpendicularly on the patient who remains lying on a translational platform, at 200 cm from the source. The purpose of this study is to perform a dosimetric characterization of this techniqu...

BACKGROUND Stereotactic radiosurgery represents a noninvasive alternative treatment for intracranial metastases. OBJECTIVE To investigate the treatment outcome of linear accelerator-based stereotactic radiosurgery (linac-SRS) for brainstem metastases. METHODS We retrospectively reviewed our database of patients who were diagnosed with brainstem metastases and underwent linac-SRS between 199...

BACKGROUND To derive and exploit the optimal prescription isodose level (PIL) in inverse optimization of volumetric modulated arc radiotherapy (VMAT) as a potential approach to dose de-escalation in stereotactic body radiotherapy for non-small cell lung carcinomas (NSCLC). METHODS For ten patients, inverse Monte Carlo dose optimization was performed to cover 95% PTV by varying prescription is...

PURPOSE To evaluate C-11 choline positron emission tomography/computed tomography (CholPET) in staging and determining patterns of recurrence in prostate cancer patients with rising prostate-specific antigen levels after prostatectomy radiation therapy (RT). METHODS AND MATERIALS The study includes patients with biochemical failure after postprostatectomy RT who underwent CholPET between 2008...

PURPOSE To develop a GPU-based Monte Carlo (MC) 3D dosimetry quality assurance (QA) tool employing patient geometry and actual delivery information. METHODS First, we generate fluence maps at all beam angles from the initial treatment plan. A GPU-based MC dose engine, gDPM, is employed for the secondary dose calculation (SDC) on patient CT. This SDC is used to verify the TPS plan dose (PD) ac...