S. Pini

PO-0825: Characterization of a commercial EPID 3d software for in vivo dosimetry

ESTRO 35 2016 ______________________________________________________________________________________________________ (MU) were delivered at each angle: The reference dose without couch attenuation is the average dose at 00,900 and 2700. Gantry angles ranging from 2350 to 2230 in 10 increments are used to measure the edge attenuated dose. And gantry angles ranging from 2200 to 1800 in 100 increments to measure the dose attenuation of the central region of the couch. Skin dose was measured with radiochromic films and FilmQA Pro. Several films were placed between RW3 slabs in different depths.The center of RW3 phantom coincides with linac isocenter. First,films were located at the surface, 0.5cm and 1.5cm from the surface, and in the center of the RW3 phantom. Then 200MU were delivered with an open 10x10 field and with zero gantry angle. The irradiated films were removed and other films were placed under the phantom, 0.5cm and 1.5cm from the couch and in the center. The opposite beam was delivered, so we measure the effect of the couch to the dose distribution in the buildup region.

A.201 - Dosimetric benefits and reproducibility of DIBH tecnique guided by an optical system

Results: The projected 2D CT bin areas for the 5 patients had a mean (standard deviation) area of 4.12(0.35), 5.17(0.40), 2.99(0.34), 9.28(0.52) and 3.96 (0.35) cm2. This is compared to the MR contoured areas of 5.02 (0.45), 7.13(0.67), 2.63(0.41), 7.52(0.57) and 4.07(0.41) cm2 (Figure 1). While there are differences that may be attributed to binning errors from 4D CT reconstruction and intra-observer variations, contours from real time MRI do not appear to be systematically biased on target area compared to the CT contours. Figure 1. Mean area for five lung tumors on CT, MRI and MIP. Error bars represent standard deviation.

Multi hospital experiences in the use of RDIM softwares to optimize radiological procedures in computed tomography, mammography and interventional radiology

Introduction Radiation Dose Index Monitoring (RDIM) are useful software tools that allow radiological data collection and patient dose monitoring. However its implementation need a thorough acceptance test. Purpose Aim of this work is to test the consistency of data processed by two RDIM software and use the dose index information archived to optimize radiological procedures in our hospitals. Materials and methods We began in 2012 to monitor dose index data from 7 CTs and 2 angiographic units using CareAnalytics (CA) tool by Siemens. CA processes DICOM RDSR stored in PACS. Moreover within an Italian project, RDM by Medsquare has been tested since Gen 2015. RDM collects and analyzes doses delivered to patients during medical imaging examinations. One mammographic installation, 2 CTs and 1 angiographic unit has been connected to RDM. Results For angiographic procedure we have compared the maximum incident air kerma at the reference point at different times and at different C arm positions with the dose values obtained by softwares. For mammography, data from header DICOM have been positively compared with RDM data. For CT we have compared values obtained from console, CA and RDM. Conclusion In our experiences both the software under test seems to be useful tools to monitor radiation dose index. RDM allows wider applications and custom made options. Disclosure Nothing to declare.