Eye lens dose measurements in Interventional Cardiology

Transcription

1 Eye lens dose measurements in Interventional Cardiology Poster No.: 479 Congress: ESCR 2014 Type: Scientific Poster Authors: N. Kollaros 1, E. Carinou 2, C. Plemmenos 1, I. Stathopoulos 1, V. Keywords: Voudris 1, I. Mastorakou 1 ; 1 Athens/GR, 2 Ag. Paraskevi/GR Ischemia / Infarction, Angioplasty, Ablation procedures, Fluoroscopy, Radioprotection / Radiation dose Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 5

2 Purpose An increased interest has been recently raised concerning eye lens doses received by the medical personnel during interventional cardiology procedures. This is due to the fact that this personnel is among the ones who are highly exposed (1). Moreover, as it is stated in ICRP 2011: "for occupational exposure in planned exposure situations, an equivalent dose limit for the lens of the eye of 20 msv per year, averaged over defined periods of 5 years, with no single year exceeding 50 msv, is recommended" (2). Though reccomendations for the specific radiation protection issues have been drafted (3), there is no clear status in the eye occupational issue yet. The present study aims at validating the eye lens protective measures during cardiology interventional procedures, as well as investigating the correlation between the Kerma Area Product (KAP) values and the eye lens dose of the main operator. Methods and Materials MCP-N thermoluminescet pellets were used for the evaluation of the doses outside and inside the radioprotective eye glasses of 5 operators. Measurements were performed in 77 procedures including coronary angiographies (CA), percutaneous transluminal coronary angioplasties (PTCA) and radiofrequency ablations (RFA). The total KAP values were also monitored in order to find a correlation between the recorded dose values and the KAP ones. Results In tables 1 and 2 the eye lens doses are shown, as recorded by the dosemeters attached outside and inside the radiation protection glasses. The ratio of the doses outside to the respective inside values is (5.0±0.3) for all the procedures, which means that if the dosemeter is attached -for practicality reasons- outside the lead glasses the "real" dose to the eye is 5 times lower. Moreover, the relationship between the eye lens dose and the respective KAP values is shown in Figure 1. As shown from the figure, the eye lens doses behind the glasses are well correlated with the recorded KAP values. The respective correlation factor is (0.126±0.014) µsv/gy cm 2. Page 2 of 5

3 Table 1: Operator doses outside and inside the lead glasses during PTCA procedures References: Department of Radiology, Onassis Cardiac Surgery Center Table 2: Operator doses outside and inside the lead glasses during RF ablation procedures References: Department of Radiology, Onassis Cardiac Surgery Center Fig. 1: The correlation between eye doses and KAP values References: DEpartment of Radiology, Onassis Cardiac Surgery Center Images for this section: Page 3 of 5

4 Table 1: Operator doses outside and inside the lead glasses during PTCA procedures Table 2: Operator doses outside and inside the lead glasses during RF ablation procedures Fig. 1: The correlation between eye doses and KAP values Page 4 of 5

5 Conclusion The dose to the eye lens of the main opeartor is 5 times lower to the dose recorded outside the eye lens glasses, which is the usual way to record doses using the specific adapted eye lens dosemeters (4). Moreover, a great help to the radiation protection officer is the ratio of the eye lens doses to the respective KAP values in order to make a very first rough estimation of the eye lens doses for the occupationally exposed personnel. The relationship between the KAP values and the respective occupational eye lens dose is difficult to be established, since staff doses are associated with a variety of parameters such as the projections of the tube, the beam collimation, the working practices and the most important of all, the use of protective devices (5). However, a good starting point for the first estimation of the eye lens dose is the use of the KAP values. References 1. F. Vanhavere, et al. Measurements of eye lens doses in interventional radiology and cardiology: Final results of the ORAMED project Radiat Meas 46(11), , ICRP 2011 Statement on Tissue Reactions ICRP reference , E. Carinou, et al. Recommendations to reduce extremity and eye lens doses in interventional radiology and cardiology Radiat. Meas. 46 (11) , J. Bilski, et al. The new EYE-D dosimeters for measurements of Hp(3) for medical staff. Radiat.Meas.46, , O. Ciraj-Bjelac and MM Rehani. Eye dosimetry in interventional radiology and cardiology: current challenges and practical considerations. Radiat Prot Dosimetry Nov 20. [Epub ahead of print] Page 5 of 5