an important need in radiation therapy is a fast and accurate treatment planning system. this system using ct data and characteristics of the radiation beam, calculates the dose in all points of the patient’s volume. two main factors in planning system are “accuracy” and “speed”. according to these factors, various generation of treatment planning systems are developed.   this article is the re...

introduction wedge modifiers are commonly applied in external beam radiotherapy to change the dose distribution corresponding to the body contour and to obtain a uniform dose distribution within the target volume. since the radiation dose delivered to the target must be within ±5% of the prescribed dose, accurate dose calculation by a treatment planning system (tps) is important. the objective ...

background: most of the current brachytherapy treatment planning systems (tps) use the tg-43u1 recommendations for dosimetry in water phantom, not considering the heterogeneity effects. objective: the purpose of this study is developing a method for obtaining correction factors for heterogeneity for cs-137 brachytherapy sources based on pre-calculated mc simulations and interpolation. method: t...

introduction: esophageal cancer is one of the most frequently occurring cancers in iran and having a  high  incidence  rate  among  other  countries.  radiotherapy  is  one  of  the  three  methods  (surgery,  radiotherapy and chemotherapy) for radical or palliative treatment of esophageal cancer. in this method  of treatment, the organs such as heart and spinal cord are regarded as organs at r...

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...

Unicystic ameloblastoma is a tumor of odontogenic origin. It is not a rare neoplasm and most often the lesion is asympthomatic. However, large lesions may cause painless swelling of the jaws. Here we report a case of unicystic ameloblastoma with pain, swelling of the posterior jaws along with teeth mobility. Samples of incisional biopsy of the lesion and also interaoperative frozen section were...

introduction: breast conserving radiotherapy is one of the most common procedures performed in any radiation oncology department. a tangential parallel-opposed pair is usually used for this purpose. this technique is performed using 2d or 3d treatment planning systems. the aim of this study was to compare 2d treatment planning with 3d treatment planning in tangential irradiation in breast conse...

background: craniospinal radiotherapy faces technical challenges which are due to the sensitivity of the location in which the gross tumor is, and to organs at risk around planning target volume. using modern treatment planning systems causes a reduction in the complexities of the treatment techniques. the most effective method to assess the dosimetric accuracy and the validity of the software ...

background: it was intended to investigate the effect of physical wedge (pw) and enhanced dynamic wedges (edw) on contralateral breast dose during primary breast irradiation in radiotherapy treatment, using high energy photon beams. materials and methods: the varian’s clinac dual mode linear accelerator model 2100 c/d and siemen’s primus accelerators were used for radiation doses with 6 mv and ...