PET/CT imaging allows for image based estimates of organ and red marrow (RM) residence times. The aim of this study was to derive PET/CT based radiation dosimetry for Zr-cetuximab, with special emphasis on determining RM absorbed dose. Methods: Seven patients with colorectal cancer received 36.9 ± 0.8 MBq Zr-cetuximab within 2 h after administration of a therapeutic dose of 500 mg⋅m of cetuxima...

PURPOSE Rats have been widely used in radionuclide therapy research for the treatment of hepatocellular carcinoma (HCC). This has created the need to assess rat liver absorbed radiation dose. In most dose estimation studies, the rat liver is considered as a homogeneous integrated target organ with a tissue composition assumed to be similar to that of human liver tissue. However, the rat liver i...

This paper discusses a methodology which uses a specially developed computer program that enables estimation of output parameters of an x-ray machine from a single test exposure. Exposure at skin entrance values can be estimated, as well as using the data from the program for organ dose estimates. To perform the estimation procedure, curves and analytical expressions for the curves are presente...

Introduction: The aim of this study is to investigate the effect of partially used high photon energies on dosimetric parameters and integral doses of nasopharynx IMRT plans.   Materials and Methods: Two 7 coplanar IMRT plan were created for eleven patients (6 MV only IMRT plan in both phase1 and phase2 and 6 MV phase1-mixed energies (6 MV and 15 MV) phase2...

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...

Automatic exposure control (AEC) in computed tomography (CT) facilitates optimisation of dose absorbed by the patient. The use of AEC requires appropriate 'patient centring' within the gantry, since positioning the patient off-centre may affect both image quality and absorbed dose. The aim of this experimental study was to measure the variation in organ and abdominal surface dose during CT exam...

background: care of brain dead donors is complex, critical, and sensitive and has a direct and positive impact on the end result of organ and tissue transplantation process. this study describes the nurses’ experiences of care of brain dead donors in intensive care units (icu). materials and methods: this research was performed by phenomenological method that is a qualitative approach. purposiv...

background: best dose distribution in target volume and control of organ at risk (oar) dose are the two main goals in brachytherapy. materials and methods: in this study in vivo dosimetry in 4 rectal points was performed by transillumination dosimeter (tld) s and the measured doses were compared in different patients. one point was reported to have the maximum dose in each patient and the very ...

Aims. To compare the effective and eye lens radiation dose in helical MDCT brain examinations using automatic tube current modulation in conjunction with either standard filtered back projection (FBP) technique or iterative reconstruction in image space (IRIS). Methods. Of 400 adult brain MDCT examinations, 200 were performed using FBP and 200 using IRIS with the following parameters: tube volt...