background: in order to deliver the precise dose to the target in radiotherapy, absorbed dose to water at the reference point should be assessed. when the calibration procedure is performed for a reference dosimeter in the 60co beam of a secondary standard dosimetry laboratory (ssdl), the total uncertainty in absorbed dose to water (dw) is estimated to be approximately 1.5%. this study attempts...

abstract background: adjacent treatment fields are commonly used in external beam radiation therapy, such as mantle and inverted-y fields for the treatment of hodgkin’s disease and craniospinal fields used in the treatment of medulloblastoma and head and neck tumors when the lateral neck fields are placed adjacent to the anterior supraclavicular field. in each of these situations, there is a po...

background: fatigue is a common side effect in cancer patients undergoing radiation therapy (rt). radiation-induced fatigue affects the quality of life, but there is no definitive treatment option. in this study, the weight-loaded forced swim test was performed to assess the effect of coenzyme q10 (coq10) on radiation-induced fatigue. materials and methods: a total of 60 rats were divided rando...

background: in conventional radiation therapy, regarding normal tissue tolerance, the treatment of bulk tumors is one of the remaining challenges. grid radiation therapy (grt) is a technique to deliver high doses, approximately 15 – 20 gy per fraction, to several small volumes located in a large radiation field. this can be performed using a grid block. the current work has concentrated on the ...

introduction intensity-modulated radiotherapy (imrt) is becoming an increasingly routine treatment method. imrt can be delivered by use of conventional multileaf collimators (mlcs) and/or physical compensators. one of the most important factors in selecting an appropriate imrt technique is integral dose. integral dose is equal to the mean energy deposited in the total irradiated volume of the p...

intraoperative radiation therapy (iort) is a multidisciplinary approach in which residual tumors or tumor beds are directly irradiated during a surgical procedure. to evaluate its efficacy, from 1985, we conducted a prospective study including non-metastatic gastric adenocarcinoma treated by surgery, iort (15 grays) and postoperative external beam radiotherapy (44 grays). up to 1993, 51 cases o...

introduction magnetic fields are capable of altering the trajectory of electron beams andcan be used in radiation therapy.theaim of this study was to produce regions with dose enhancement and reduction in the medium. materials and methods the ndfeb permanent magnets were arranged on the electron applicator in several configurations. then, after the passage of the electron beams (9 and 15 mev va...

background and aims. the antioxidant and anti-inflammatory properties of propolis were studied. since saliva contains antioxidants and radiotherapy of the head and neck mainly affects the saliva, salivary antioxidant defensive mechanism is compromised with oxidative stress produced by radiation therapy. therefore, the aim of the present study was to investigate the effect of propolis on salivar...

background: an effective method for management of large and bulky malignant tumors. this treatment modality is also known as specially fractionated radiation therapy (sfrt). in this treatment technique a grid block converted the open radiation field into a series of pencil beams. dosimetric characteristics of an external beam grid radiation field have been investigated using experimental and mo...