RESUMEN
In this study, measurements of dose-area product (DAP) and entrance surface dose (ESD) were carried out in a sample of 25 adult patients who underwent intravenous urography (IVU). These measured quantities were used to estimate the effective dose E from the IVU examination, a quantity closely correlated to radiation risk. Estimating E involves the use of conversion coefficients that have been determined for specific X-ray views in a mathematical phantom. These are obtained under conditions which are not usually met in clinical practice. As a result, the E estimates using the two different measurable quantities can be quite different. Analysis of the calculation procedure suggests that the E estimate using the DAP measurements, in addition to being more practical, could be more accurate than using ESD measurements, as DAP is sensitive to the X-ray field size settings. Furthermore, it is shown that in the absence of the appropriate equipment, a reliable E estimate can be obtained from the ESD calculated using the exposure data for each X-ray view.
Asunto(s)
Dosis de Radiación , Urografía , Adulto , Calibración , Femenino , Humanos , Masculino , Fantasmas de Imagen , Radiometría/métodos , Piel/efectos de la radiaciónRESUMEN
Total skin electron beam therapy has been in medical service since the middle of the last century in order to confront rare skin malignancies. Since then various techniques have been developed, all aiming at better clinical results in conjunction with less post-irradiation complications. In this article every available technique is presented in addition to physical parameters of technique establishment and common dose fractionation. This study also revealed the preference of the majority of institutes the last 20 years in "six dual field technique" at a high dose rate, which is a safe and effective treatment.