Since the introduction of volumetric chemical dosimetry with Fricke gel dosimeters in the 1980s, three-dimensional (3D) dosimetry has been a promising technique for the clinic, since it provides a unique methodology for 3D dose measurement of the complex conformal dose distributions achieved by modern techniques such as Intensity Modulated and Volumetric Arc Radiation Therapy. In the last decad...

High dose rate brachytherapy (HDR) using 192Ir sources is well accepted as an important treatment option and thus requires an accurate dosimetry standard. However, a dosimetry standard for the direct measurement of the absolute dose to water for this particular source type is currently not available. An improved standard for the absorbed dose to water based on Fricke dosimetry of HDR 192Ir brac...

Routine internal dose exposures are typically (in the UK nuclear industry) less than external dose exposures: however, the costs of internal dosimetry monitoring programmes can be significantly greater than those for external dosimetry. For this reason decisions on when to apply routine monitoring programmes, and the nature of these programmes, can be more critical than for external dosimetry p...

UNLABELLED Compared with conventional, whole-organ, S-factor-based dosimetry, 3-dimensional (3D), patient-specific dosimetry better accounts for radionuclide distribution and anatomic patient variability. Its accuracy, however, is limited by the quality of the cumulated activity information that is provided as input. This input has typically been obtained from SPECT and planar imaging studies. ...

background : the portal system and azygos vein are the main drainage systems during portal hypertension. this study aims to compare the diameter of these veins by endoscopic ultrasonography (eus) inpatients with and without chronic liver disease (cld). materials and methods : during one year, patients with cld enrolled as the study group. patients who underwent eus for other reasons during the ...

The increasing risk of a mass casualty scenario following a large scale radiological accident or attack necessitates the development of appropriate dosimetric tools for emergency response. Luminescence dosimetry has been reliably applied for dose reconstruction in contaminated settlements for several decades and recent research into new materials carried close to the human body opens the possib...

Accuracy in the delivered dose to the patients plays an important and vital role in radiotherapy treatments. This happens because of steep gradient of dose-local control and dose-normal tissue complication probability curves. Dosimetric uncertainty of 3%-4% (one standard deviation) in the delivered dose to the target volume as an acceptable level has been recommended(1-3). In many centers, in v...

background portal vein thrombosis (pvt) is one of the most common causes of extrahepatic portal hypertension in children, which may follow neonatal umbilical vein catheterization. the incidence rates of catheter-related pvt, in infants and children vary in different studies. this study aimed to determine pvt incidence in the children under 3 years old with a history of neonatal umbilical vein c...

abstractbackground: delivering the radiation dose to the target volume and minimizing the dose to normal tissues are the main objectives in radiotherapy. the aim of our study is to enhance the contrast of the portal image to increase the accuracy of delineation of the organs in the irradiation field.   methods: the software was written based on local enhancement of the pixel values in image mat...

In this article we discuss examples of challenging problems in retrospective dosimetry and describe some promising solutions. The ability to make measurements by accelerator mass spectrometry and luminescence techniques promises to provide improved dosimetry for regions of Belarus, Ukraine and Russian Federation contaminated by radionuclides from the Chernobyl accident. In addition, it may soon...