Development of a system to estimate doses in real time

• Published in: Radiation physics and chemistry (Oxford, England : 1993) Vol. 167; p. 108267
• Main Authors: de Camargo Lourenco, Jose Carlos, Paschuk, Sergei Anatolyevich, Schelin, Hugo Reuters, Denyak, Valeriy, Santos, César Antonio Caggiano
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2020; Elsevier BV
• Subjects: Data collection; Dosimeters; Estimated dose; Exposure; Fluoroscopy; Gonads; Ground level; Interventionist physician; Ionization chambers; Ionizing radiation; Medical personnel; Real time; Real-time system; Time measurement; Real-time system; Ionizing radiation; Estimated dose; Interventionist physician
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/j.radphyschem.2019.04.017

In interventionist procedures that use fluoroscopy, medical staff are exposed to ionizing radiation, often with doses exceeding the recommended limits. These doses are only observed at the end of the procedure, or after one month by means of individual dosimeters. The objective of the present study was to develop a system to estimate doses of ionizing radiation in real time during the interventionist medical procedure using fluoroscopy. The performance of the remote-controlled fluoroscopy system in scattered radiation measurements was tested at 50 kV and 30 mA with a Ludlum 9DP ionization chamber and a PMMA phantom. Dose rates were collected by the ionization chamber for the regions of the gonads at 90 cm in relation to the ground level, with distances of the main beam at 27, 54, 108 and 214 cm, around the fluoroscopy table at 45°–45°. To estimate doses in real time, an ionization chamber was attached to the top of the fluoroscopy table and used as a fixed reference point. The collected data were sent to the developed software to determine the estimated doses. The estimated doses were visualized in real time through a display showing the intensities of the accumulated doses with a visual indication of color scale for the doses received by the members of the medical staff. To validate the estimate doses in real-time system, the hypothesis of the measured dose rates and the estimated real-time measures were implemented using Student's t-test for independent samples with a significance level of 5%. We valuate the equivalent dose estimate in two different size phantoms with heights during an average time of exposure of scattered radiation in 13-min, which corresponds on average to an interventional procedure, and we respectively found the following estimates in the phantom 25 × 25 × 7 cm: 76.0, 27.0, 6.0 and 0.3 μSv, and the other of 30 × 30 × 15 cm: 686.2, 245.1, 53.7 and 2.5 μSv, respectively measured in real time at a height of 90 cm, in the region of the gonads. The estimated dose in real time helps the interventionist physician optimize their exposure to scattered radiation during the intervention procedure, allowing them to enhance personal protection and reduce occupational dose. •Estimates of real-time cumulative doses.•Real-time scattered radiation monitoring.•Visualization of estimated doses in real-time.•Optimization of the physicians' position to reduce the dose received.•Techniques for reducing scattered radiation in fluoroscopy guided system.