medical x-rays are the largest man-made source of public exposure to ionizing radiation. while the benefits of computed tomography (ct) are well known in accurate diagnosis, those benefits are not risk free. ct is a device with higher patient dose in comparison with other conventional radiation procedures. so it is important to avoid conditions where the amount of radiation used is more than th...

Background: Positron Emission Tomography-Computed Tomography (PET-CT) is a useful hybrid imaging modality in the diagnosis of various malignancies. This modality imposes almost 20 mSv radiation dose to the patient. The purpose of the present study was to evaluate the uncertainties in calculated CT effective dose in TUBE CURRENT MODULATION-activated scans by Impact-Dose software.  Materials and ...

Introduction: In recent years, the number of computed tomography (CT) scans, which is a high-dose technique, has increased significantly. Head and neck CT is performed frequently and thyroid, particularly in children, has always been considered a sensitive organ. In recent years, radiobiologists and health physicists have been more concerned about the safety of lenses of the eyes, as cataract i...

background: to reduce uncertainties of patient positioning, the computerized tomography (ct) images acquired at the treatment planning time can be compared with those images obtained during radiation dose delivery. this can be followed during dose delivery procedure as image guided radiotherapy (igrt) to verify the prescribed radiation dose delivery to the target as well as to monitor radiation...

Introduction: Tumor volume delineation is the most important step in the radiation treatment planning. In this study the impact of PET/CT data on the tumor delineation precision of non-small cell lung cancer (NSCLC) was investigated. Methods: PET/CT images of 20 patients with primary NSCLC were obtained and imported to the treatment planning system for im...

objective: resistance of metastatic lymph nodes (lns) to high dose i-131 therapy is associated with high morbidity in patients with differentiated thyroid cancer. we evaluated the role of f-18 fdg pet/ct in the prediction of resistance to high dose i-131 therapy in patients with papillary thyroid cancer. methods: the subjects were 307 patients who underwent total or near total thyroidectomy fol...

Background: To reduce uncertainties of patient positioning, the Computerized Tomography (CT) images acquired at the treatment planning time can be compared with those images obtained during radiation dose delivery. This can be followed during dose delivery procedure as Image Guided radiotherapy (IGRT) to verify the prescribed radiation dose delivery to the target as well as to monitor ...

Background: Breast cancer is a common disease in radiation oncology. We evaluated the radiation dose received by breast cancer patients, an often-neglected concern. Materials and Methods: The total effective radiation dose in 101 breast cancer patients was calculated by summing the effective doses of individual diagnostic imaging tests from the first hospital visit to the initiation of radiothe...