Details Purpose: To compare the image quality of magnetic resonance (MR) treatment-planning images and proton resonance frequency (PRF) shift thermography images and inform coil selection for MR-guided laser ablation of tumors in the head and neck region. Methods: Laser ablation was performed on an agar phantom and monitored via MR PRF shift thermography on a 3T scanner, following acquisition o...

PURPOSE We developed a system for calculating patient positional displacement between digital radiography images (DRs) and digitally reconstructed radiography images (DRRs) to reduce patient radiation exposure, minimize individual differences between radiological technologists in patient positioning, and decrease positioning time. The accuracy of this system at five sites was evaluated with cli...

RapidArc is a novel treatment planning and delivery system that has recently been made available for clinical use. Included within the Eclipse treatment planning system are a number of different optimization strategies that can be employed to improve the quality of the final treatment plan. The purpose of this study is to systematically assess three categories of strategies for four phantoms, a...

  Introduction: In patients with thyroid carcinoma, radiation absorbed doses of the thyroid and surrounding tissues is important to weigh risk and benefit considerations. In nuclear medicine, the accuracy of absorbed dose of internally distributed radionuclides is estimated by different methods such as MIRD and direct method using TLD. The aim of this study is using T...

The purpose of this investigation was to evaluate the dose on megavoltage CT (MVCT) images required for tomotherapy. As imaging possibilities are often used before each treatment and usually used several times before the session, we tried to evaluate the dose delivered during the procedure. For each scanning mode (fine, normal, and coarse), we first established the relative variation of these d...

The image-guided CyberKnife radiosurgery system is apable of tracking spinal targets without fiducial implants. Recently, a new version of this fiducial-free image guidance modality ("enhanced Xsight spine tracking") has been introduced. We assessed the accuracy of this novel technique versus its precursor in a comparative phantom study. The CyberKnife consists of a 6 MV linac on a six-axis rob...

background: the purpose of this study is to fabricate inexpensive in-house low cost homogeneous and heterogeneous human equivalent thorax phantom and assess the dose accuracy of the treatment planning systems (tps) calculated values for different lung treatment dosimetery. it is compared with thermoluminescent dosimeter (tld) measurement. materials and methods: homogeneous and heterogeneous tho...

IMRT often requires delivering small fields which may suffer from electronic disequilibrium effects. The presence of heterogeneities, particularly low-density tissues in patients, complicates such situations. In this study, we report on verification of the DPM MC code for IMRT treatment planning in heterogeneous media, using a previously developed model of the Varian 120-leaf MLC. The purpose o...

PURPOSE To design a Head and Neck (H&N) anthropomorphic QA phantom that the Imaging and Radiation Oncology Core Houston (IROC-H) can use to verify the quality of intensity modulated proton therapy (IMPT) H&N treatments for institutions participating in NCI clinical trials. METHODS The phantom was created to serve as a remote auditing tool for IROC-H to evaluate an institution's IMPT planning ...