background: the shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. these methods include lead standard blocks, individual molding and multi leaf collimator (mlc). the mlc method is not still common in iran radiotherapy centers. individual molding is better than the lead block shield...

9.1 Background to Proton Therapy The use of proton beams for radiation treatment was proposed by Robert R. Wilson in 1946 [286]. Wilson referred to the ballistical aspects of the proton beam dose distribution as a rationale for the new modality. Heavy charged particles such as protons produce an energy deposition profile in tissue which is superior to profiles attainable using photon or electro...

background: natural background radiation of a particular region is one of the distinctive factors defining the status of environment. eloor island is an industrial area in ernakulum district of the state of kerala, india. the indoor and outdoor gamma level measurements have been carried out for the region for evaluating the annual effective dose to the population residing in this area. material...

The American College of Radiology opened the computed tomography (CT) dose index registry (DIR) for general participation by all facilities in 2011. For each CT examination, data on volume CT dose index (CTDIvol), dose-length product (DLP), and, for body examinations, size-specific dose estimate (SSDE) were collected. However, effective dose is not estimated in DIR. The primary objective of thi...

Introduction:Obesity is one of the most serious challenges of our era, with significant health consequences and high economic burden for health systems. Therefore, many countries have developed political agendas to cope with this ever-rising challenge. Along with chemical medications that are developed to manage obesity, researchers have focused on some natural ingredients and herbal extracts w...

cavernous hemangioma is a rare benign tumor of the internal auditory canal (iac) of which fourteen cases have been reported so far. tinnitus and progressive sensorineural hearing loss (snhl) are the chief complaints of the patients. audiological and radiological planes, ctscan, and magnetic resonance image (mri) studies are helpful in diagnosis. the only choice of treatment is surgery with elec...

Recently the compensator has been shown to be an in expensive and reliable dose delivery device for photon beam intensity-modulated radiation therapy (IMRT). The goal of IMRT compensator design is to produce an optimized primary fluence profile at the patient's surface obtained from the optimization procedure. In this paper some of the problems associated with IMRT compensator design, specifica...

BACKGROUND The technologic improvements in Multislice scanners include the increment in the X-ray beam width. Some new CT scanners are equipped with a 320 detector row which allows a longitudinal coverage of 160 mm and a total of 640 slices for a single rotation. When such parameters are used the length of the traditional pencil chamber (10 cm) is no more appropriate to measure the standard wei...

introduction in neonates and small infants, early diagnosis of central diabetes insipidus (cdi) and treatment with desmopressin in low doses (avoiding severe hypo- or hypernatremia) are important to prevent associated high morbidity and mortality in this particular age group. case presentetion we described pharmacokinetic and pharmacodynamic results of the use of recently launched oral desmopre...