The purpose of this study is to evaluate the dosimetric accuracy of MRI-based treatment planning for prostate cancer using a commercial radiotherapy treatment planning system. Three-dimensional conformal plans for 15 prostate patients were generated using the AcQPlan system. For each patient, dose distributions were calculated using patient CT data with and without heterogeneity correction, and...

background: in treating patients with radiation, the degree of accuracy for the delivery of tumor dose is recommended to be within ± 5% by icru in report 24. the experimental studies have shown that the presence of low-density inhomogeneity in areas such as the lung can lead to a greater than 30% change in the water dose data. therefore, inhomogeneity corrections should be used in treatment pla...

background: acrylamide (c3h5no) is a vinyl monomer. this water-soluble crystalline solid is a colorless, odorless agent which is used in scientific laboratories and some industries. acrylamide has cellular oxidative effects. acute or chronic poisoning with this agent happens as a result of skin, respiratory, or oral contacts. clinical manifestations depend on the dose, duration, and frequency o...

The aim of this study was to investigate and, if possible, compensate for the effect of intravenous contrast-enhanced CT scans on the treatment planning dose distributions for lung patients. The contrast and noncontrast CT scans of 3 patients were registered, and the effect of contrast on the Hounsfield units (HU) was assessed. The effect of contrast was then simulated in the CT scans of 18 pat...

PURPOSE An analytical and experimental study of split shape dose calculation correction by adjusting the position of the on-axis round leaf end position is presented. We use on-axis corrected results to predict off-axis penumbra region dosimetric performance in an intensity-modulated radiation therapy treatment planning system. MATERIALS AND METHODS The precise light-field edge position (X(ta...

background: accelerated partial breast irradiation via interstitial balloon brachytherapy is a fast and effective treatment method for certain early stage breast cancers however skin, chest wall and lung doses are correlated with toxicity in patients treated with breast brachytherapy. objective: to investigate the percentage of the dose received by critical organ (skin), thermoluminescence dete...

Introduction: This study examined the dosimetric effects based on the rotational setup error to correct patient setup errors occur during volumetric modulated arc radiotherapy (VMAT) for brain tumor patients. Material and Methods: This study included 1129 cases of cone beam computed tomography (CBCT) images obtained from 46 brain tumor patients, who experienced VMAT and used the 6DoF (degree o...

Introduction: Contura is a balloon applicator that used to deliver intra cavity radiation for Partial Breast Irradiation (PBI) treatments. Contura with 4 peripheral lumens surrounding the central, for loading HDR sources from an after loader system can provide an asymmetric dose distribution and gives a more flexible shape of dose than earlier balloon applicators such as Mammo...

objective: acute inflammatory demyelinating peripheral neuropathy (guillain-barre-syndrome) is by far the most common cause of immune-medicated peripheral nervous system disease in children; with the near disappearance of poliomyelitis, gbs is responsible for the great majority of cases of acute flaccid paralysis. so far, in several controlled studies, corticosteroids, plasmapheresis and ivig h...

Background: In treating patients with radiation, the degree of accuracy for the delivery of tumor dose is recommended to be within ± 5% by ICRU in report 24. The experimental studies have shown that the presence of low-density inhomogeneity in areas such as the lung can lead to a greater than 30% change in the water dose data. Therefore, inhomogeneity corrections should be used in treatment pla...