Background: In order to deliver the precise dose to the target in radiotherapy, absorbed dose to water at the reference point should be assessed. When the calibration procedure is performed for a reference dosimeter in the 60Co beam of a Secondary Standard Dosimetry Laboratory (SSDL), the total uncertainty in absorbed dose to water (Dw) is estimated to be approximately 1.5%. This study attempts...

Coronary artery multiple fistulae of the left ventricular chamber are extremely rare congenital malformations. We report on 13-year-old monozygotic twin brothers who have identical abnormalities of coronary flow reserve as well as the same morphological findings of multiple coronary fistulae of the 3 major coronary arteries to the left ventricular chamber. The left circumflex coronary artery (L...

There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE) and a commercial optic...

PURPOSE The goal of any dosimeter is to be as accurate as possible when measuring absolute dose to compare with calculated dose. This limits the uncertainties associated with the dosimeter itself and allows the task of dose QA to focus on detecting errors in the treatment planning (TPS) and/or delivery systems. This work introduces enhancements to the measurement accuracy of a 3D dosimeter comp...

Results of the measurement of indoor radon and thoron carried out in and around Srirampura, Bangalore, India using passive detector technique is presented. Measurements were carried out using twin cup radon-thoron dosimeter using small strips of 12 micron thick LR-115 Type II nuclear track detectors. Measurements were carried out in 60 dwellings for a period of one year on a quarterly time inte...

PURPOSE To estimate the heritabilities of myopia and ocular biometrics among different family types among a Korean population. METHODS We studied 1508 adults in the Healthy Twin Study. Spherical equivalent, axial length, anterior chamber depth, and corneal astigmatism were measured by refraction, corneal topography, and A-scan ultrasonography. To see the degree of resemblance among different ...

Radiation processing in many areas, particularly in radiation sterilization, demands control of the absorbed dose. Many dosimeters have been proposed for the high-level dose range (region of 10 to 50 kGy). However, in addition to the required reproducibility, reliability or uncertainty (< 5%), it is desirable for radiation processing that the selected dosimetric system is easy to operate. One o...

Some of the lowest voltages used in radiotherapy are termed Grenz and superficial X-rays of ~ 20 and ~ 100 kVp, respectively. Dosimetrically, the surface doses from these beams are calculated with the use of a free in-air air kerma measurement combined with a backscatter factor and the appropriate ratio of mass energy absorption coefficients from the measurement material to water. Alternative t...