BACKGROUND The purpose of the present study is to compare finite size pencil beam (fsPB) and Monte Carlo (MC) based optimization of lung intensity-modulated stereotactic radiotherapy (lung IMSRT). MATERIALS AND METHODS A fsPB and a MC algorithm as implemented in a biological IMRT planning system were validated by film measurements in a static lung phantom. Then, they were applied for static l...

Objectives. To (1) compare the radiation dose of low-dose computed tomography (CT) to that of standard-dose CT, (2) determine the minimum optimal radiation dose for use in patients who need endoscopic sinus surgery, and (3) assess the reliability of iterative model reconstruction. Study Design. Prospective single-institution study. Setting. Tertiary care center. Subjects and Methods. We recruit...

background: the most efficient application of ionizing radiation is serving medical purposes and using this radiation has caused people to learn that artificial sources of radiation exposure among these resources can be of highest exposure rate.   objective: the present study is aimed at initially establishing a baseline for local-reference dose level in mazandaran, iran in 12 projections of th...

Over the last few years, computed tomography (CT) has developed into a standard clinical test for a variety of cardiovascular conditions. The emergence of cardiovascular CT during a period of dramatic increase in radiation exposure to the population from medical procedures and heightened concern about the subsequent potential cancer risk has led to intense scrutiny of the radiation burden of th...

background: the aim of this study was to evaluate the reduction in excision cavity volume (ecv) during the whole breast radiotherapy (wbrt). the delineating of reduced cavity volume on secondary ct (computed tomography) might decrease the field size of boost plan. materials and methods: twenty patients were treated having breast conservative surgery. at first, primary ct simulation (ct-1) was d...

Computed tomography (CT) is a prominent procedure in the US with larger radiation doses than traditional radiology. CT is a powerful tool in the diagnosis of a wide variety of conditions and its use has grown quickly because of its power. CT contributes a significant portion of annual per capita dose in the US. The risk of this additional dose is poorly understood. The risks of low doses of rad...

Background: Brachytherapy treatment planning in cervix carcinoma patients using two dimensional (2D) orthogonal images provides only point dose estimates while CT-based planning provides volumetric dose assessment helping in understanding the correlation between morbidity and the dose to organs at risk (OARs) and treatment volume. Objective: Aim of present study is to compare Internationa...

Magnetic resonance imaging (MRI) uses a constant magnetic field and radio waves, a non-invasive method for examining tissues, organs and the skeletal system. Advantages and disadvantages of MRI are not fully understood; however, it has been commonly used in the diagnosis of skeleton and bone diseases (such as disk and spinal disorders, joint disorders (arthritis), bone tumours and tissues...