Study Evaluates Cranial Radiation Exposure in Invasive Cardiologists

August 21, 2015—Findings from the BRAIN study of brain radiation exposure and attenuation during invasive cardiology procedures were published by Ryan R. Reeves, MD, et al in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions (2015;8:1197–1206). The BRAIN study sought to determine radiation exposure across the cranium of cardiologists and the protective ability of a nonlead, XPF (barium sulfate/bismuth oxide) layered cap (BLOXR Solutions, LLC) during fluoroscopically guided, invasive cardiovascular procedures.

The investigators concluded that radiation exposure to invasive cardiologists is significantly higher on the left and center compared with the right side of the cranium. They advised that exposure may be reduced similar to an ambient control level by wearing a nonlead XPF cap. 

As noted in JACC: Cardiovascular Interventions, radiation exposure is a potential occupational hazard for staff and physicians during fluoroscopically guided invasive medical procedures, and recent reports of left-sided brain malignancies have heightened awareness among invasive cardiologists. Future studies are required to evaluate additional strategies to reduce occupational hazards for invasive cardiologists.

In the BRAIN study, invasive cardiologists wore an XPF cap with radiation attenuation ability. Six dosimeters were fixed across the outside and inside of the cap (left, center, and right), and three dosimeters were placed outside the catheterization lab to measure ambient exposure. Seven cardiology fellows and four attending physicians (38.4 ± 7.2 years of age; all male) performed diagnostic and interventional cardiovascular procedures (n = 66.2 ± 27 cases/operator; fluoroscopy time, 14.9 ± 5 min). 

The investigators found that there was significantly greater total radiation exposure at the outside left and outside center (106.1 ± 33.6 mrad and 83.1 ± 18.9 mrad, respectively) versus outside right (50.2 ± 16.2 mrad) locations of the cranium. The XPF cap attenuated radiation exposure (42.3 ± 3.5 mrad, 42.0 ± 3 mrad, and 41.8 ± 2.9 mrad at the inside left, inside center, and inside right locations, respectively) to a level slightly higher than that of the ambient control (38.3 ± 1.2 mrad). After subtracting ambient radiation, exposure at the outside left was 16 times higher than the inside left and 4.7 times higher than the outside right. Exposure at the outside center location was 11 times higher than the inside center, whereas no difference was observed on the right side, reported the investigators in JACC: Cardiovascular Interventions.