introduction in order to treat uveal melanoma , first, radioactive seeds are laid on a silicone- made substance which is called silastic after that they are inserted in the plaque, and finally, this plaque containing silicone-made substance is stitched to the sclera surface. the dose gradient within the tumor and healthy tissues can be varied due to changing the silastic thickness between scler...

background: radiotherapy plays an important role in the management of most malignant and many benign primary central nervous system (cns) tumors. radiotherapy affects both tumor cells and uninvolved normal cells; so, it is important to estimate absorbed dose to organs at risk in this kind of treatment. the aim of this study was to determine the absorbed dose to chiasma, lens, optic nerve, retin...

introduction radiotherapy is regarded as the first treatment of choice for nasopharyngeal carcinoma. despite the advantages of radiotherapy, patients may suffer from a wide range of side-effects due to the presence of many sensitive normal tissues in these regions. if the absorbed dose exceeds the tolerance level in parotid glands and the spinal cord, myelopathy, lhermitte's sign and xeros...

background: sentinel node biopsy (slnb) is the standard of care for breast cancer treatment and it is getting wide acceptance in iran. the radiation safety of the procedure has been investigated under controlled conditions, but the standard dose of radiotracer and techniques are not always observed in the community setting. the aim of this study was to assess the magnitude of the absorbed doses...

Experimentally determined relationships between 6°Co radiation dose and inactivation of combining activity of anti-PAB indicated that a relatively large number of reactions were associated with inactivation. A progressive increase in gross molecular disorganization with increasing radiation dose was indicated by a change in viscosity. Some degree of molecular rearrangement was also suggested by...

Introduction In order to treat uveal Melanoma , first, radioactive seeds are laid on a silicone- made substance which is called Silastic after that they are inserted in the plaque, and finally, this plaque containing silicone-made substance is stitched to the sclera surface. The dose gradient within the tumor and healthy tissues can be varied due to changing the Silastic thickness between scler...

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...

introduction in computed tomography (ct) technology, an optimal radiation dose can be achieved via changing radiation parameters such as ma, pitch factor, rotation time and tube voltage (kvp) for diagnostic images. materials and methods in this study, the brain, abdomen, and thorax scaning was performed using toshiba 16-slice scannerand standard aapm and ctdi phantoms. aapm phantom was used for...

Introduction Radiotherapy is regarded as the first treatment of choice for nasopharyngeal carcinoma. Despite the advantages of radiotherapy, patients may suffer from a wide range of side-effects due to the presence of many sensitive normal tissues in these regions. If the absorbed dose exceeds the tolerance level in parotid glands and the spinal cord, myelopathy, Lhermitte's sign and xerostomia...