PURPOSE The deformable registration of pulmonary computed tomography images before and after radiation therapy is challenging due to anatomic changes from radiation fibrosis. We hypothesize that a line-enhanced registration algorithm can reduce landmark error over the entire lung, including the irradiated regions, when compared to an intensity-based deformable registration algorithm. MATERIAL...

introduction the purpose of this study was to estimate organ and effective doses in patients undergoing some common x-ray examinations in sabzevar, iran. the effective dose is one of the best parameters for describing the amount of radiation dose received by a patient undergoing any diagnostic x-ray examination. the public dose from x-ray examinations depends on various factors, and its contrib...

background: ionizing radiation is present in all environment of the earth’s surface, beneath the earth and in the atmosphere. human beings are exposed to external radiation from their surroundings naturally and also to internal radiation from food, water and air they consume. then, it is important to measure and develop knowledge about radiation. objective: this study is designed to evaluate th...

OBJECTIVE To quantify the radiation dose enhancement in a human tissue-equivalent polymer gel impregnated with silver nanoparticles. METHODS The case-control study was conducted at the Bahawalpur Institute of Nuclear Medicine and Oncology, Bahawalpur, Pakistan, in January 2014. Silver nanoparticles used in this study were prepared by wet chemical method. Polymer gel was prepared by known quan...

PURPOSE To determine the cataractogenic potential dose of high velocity iron ions as a fixation of dose administered singly or fractionated. The dose is critical to risk assessment and to theories of radiation action and cataractogenesis. METHODS Twenty-eight-day-old rats were examined by slit-lamp biomicroscopy on a weekly-bi-weekly basis for more than 2 yr after radiation exposure. For the ...

exposure to radiation from different types of television sets was measured to ascertain the levels of hazards posed to the human biological system. measurement of the annual radiation dose hazards was performed using a halogen-quenched gm tube with thin mica end window having a density of 1.5 mg/cm2, effective window diameter of 0.360 inch and side wall of 0.012 inch thick. the gm tube was plac...

Background: Normoxic type MAGICA gel dosimeters are established for dose quantification in three dimensions for radiotherapy. Objective(s): The ability of MAGICA polymer gel was assessed by experimental measurements method for studying the effect of gold nanoparticles (GNPs) in dose enhancement under the external 18MV radiotherapy practices. <...

BACKGROUND AND PURPOSE Gamma knife radiosurgery is an alternative for the treatment of medically refractory trigeminal neuralgia. Few reports of posttreatment MR imaging appearance of cranial nerve V exist. Our purpose was to define MR imaging characteristics in cranial nerve V after gamma knife radiosurgery. METHODS We retrospectively reviewed MR images of 15 patients who underwent gamma kni...

In the recent years, application of nanoparticles in diagnosis and treatment of cancer has been the issue of extensive research. Among these studies some have focused on the dose enhancement effect of gold nanoparticles (GNPs) in radiation therapy of cancer. On the other hand, some studies indicated energy dependency of dose enhancement effect, and the others have studied the GNP size effect in...

background: the assessment of rbe quantity in the treatment of cancer tumors with proton beams in treatment planning systems (tps) is of high significance. given the significance of the issue and the studies conducted in the literature, this quantity is fixed and is taken as equal to 1.1. objective: the main objective of this study was to assess rbe quantity of proton beams and their variations...