A E Rolls1, S Rosen1, J Constantinou1, M Davis1, J Cole2, M Desai1, D Stoyanov3, T M Mastracci4. 1. Aortic Team, Department of Vascular Surgery, Royal Free London Foundation Trust, Pond Street, London NW3 2QG, United Kingdom. 2. Radiological Physics and Radiation Safety, Royal Free London NHS Foundation Trust, Pond Street, London NW3 2QG, United Kingdom. 3. Centre for Medical Image Computing and Department of Computer Science University College London, Malet Place, London WC1E 6BT, United Kingdom. 4. Aortic Team, Department of Vascular Surgery, Royal Free London Foundation Trust, Pond Street, London NW3 2QG, United Kingdom. Electronic address: tara.mastracci@nhs.net.
Abstract
OBJECTIVES: Fenestrated endovascular aneurysm repair (FEVAR) exposes operators and patients to considerable amounts of radiation. Introduction of fusion of three-dimensional (3D) computed tomography (CT) with intraoperative fluoroscopy puts new focus on advanced imaging techniques in the operating environment and has been found to reduce radiation and facilitate faster repair. The aim of this study is to evaluate the radiation dose effect of introducing a team-based approach to complex aortic repair. METHODS: Procedural details for a cohort of 21 patients undergoing FEVAR after fusion-guided (Modern Group) imaging was introduced are compared with 21 patients treated in the immediate 12 months prior to implementation (Historic Group) at a centre with expertise in FEVAR. Non-parametric tests were used to compare procedure time (PT), air kerma, dose-area product (DAP), fluoroscopy time (FT), estimated blood loss (EBL) and pre- and post-operative estimated glomerular filtration rate (eGFR) between the groups. RESULTS: Change in operative approach resulted in a significant reduction in PT for the Modern group (median 285 mins; interquartile range 268-322) compared with the Historic group (450 mins; IQR 360-540 p = <0.001). There were reductions in skin dose for the Modern group (1.6 Gy; IQR 1.09-2.1) compared with the Historic group (4.4 Gy; 3.2-7.05 p = <0.001), and DAP (Modern 159 Gy.cm2; IQR 123-226 vs 264.93 Gy.cm2; 173.3-366.8 for Historic (p = 0.006). There were no significant differences in FT, and pre- and post-operative eGFR between the two groups. Weight and height were distributed equally across both groups. Structured dose reports including the changes in frame rate were not available for analysis. CONCLUSIONS: Implementation of a team-based approach to radiation reduction significantly reduces radiation dose. These findings suggest that the radiation safety awareness that accompanies the introduction of fusion imaging may improve the overall radiation safety profile of FEVAR for patients and providers.
OBJECTIVES: Fenestrated endovascular aneurysm repair (FEVAR) exposes operators and patients to considerable amounts of radiation. Introduction of fusion of three-dimensional (3D) computed tomography (CT) with intraoperative fluoroscopy puts new focus on advanced imaging techniques in the operating environment and has been found to reduce radiation and facilitate faster repair. The aim of this study is to evaluate the radiation dose effect of introducing a team-based approach to complex aortic repair. METHODS: Procedural details for a cohort of 21 patients undergoing FEVAR after fusion-guided (Modern Group) imaging was introduced are compared with 21 patients treated in the immediate 12 months prior to implementation (Historic Group) at a centre with expertise in FEVAR. Non-parametric tests were used to compare procedure time (PT), air kerma, dose-area product (DAP), fluoroscopy time (FT), estimated blood loss (EBL) and pre- and post-operative estimated glomerular filtration rate (eGFR) between the groups. RESULTS: Change in operative approach resulted in a significant reduction in PT for the Modern group (median 285 mins; interquartile range 268-322) compared with the Historic group (450 mins; IQR 360-540 p = <0.001). There were reductions in skin dose for the Modern group (1.6 Gy; IQR 1.09-2.1) compared with the Historic group (4.4 Gy; 3.2-7.05 p = <0.001), and DAP (Modern 159 Gy.cm2; IQR 123-226 vs 264.93 Gy.cm2; 173.3-366.8 for Historic (p = 0.006). There were no significant differences in FT, and pre- and post-operative eGFR between the two groups. Weight and height were distributed equally across both groups. Structured dose reports including the changes in frame rate were not available for analysis. CONCLUSIONS: Implementation of a team-based approach to radiation reduction significantly reduces radiation dose. These findings suggest that the radiation safety awareness that accompanies the introduction of fusion imaging may improve the overall radiation safety profile of FEVAR for patients and providers.