C-Arm Angulation During Complex TEVAR Procedures Shown to Increase Radiation Exposure to Operator's Head

April 8, 2015—A single-center study showing that angulation of the C-arm during complex endovascular repair of thoracoabdominal aortic aneurysm (TAAA) increases radiation to the operator's head was published by Mostafa A. Albayati, MD, et al in the European Journal of Vascular and Endovascular Surgery (EJVES. 2015;49;396–402). 

The investigators’ aims were to directly measure exposure to radiation of the bodies and heads of the operating team during endovascular repair of TAAAs (TEVAR), and to identify factors that may increase exposure.

As summarized in EJVES, the investigators studied consecutive elective branched and fenestrated TAAA repairs performed in a hybrid operating room between October 2013 and July 2014. Electronic dosimeters were used to directly measure radiation exposure to the primary (PO) and assistant (AO) operator in three different areas (underlead, overlead, and head). Fluoroscopy and digital subtraction angiography (DSA) acquisition times, C-arm angulation, and PO/AO height were recorded.

The investigators analyzed 17 cases (Crawford II–IV), with a median operating time of 280 minutes. Median age was 76 years and median body mass index was 28 kg/m2. Stent grafts incorporated branches only, fenestrations only, or a mixture of branches and fenestrations.

A total of 21 branches and 38 fenestrations were cannulated and stented. Head dose was significantly higher in the PO compared with the AO (median 54 μSv vs 15 μSv), as was overlead body dose (median 80 μSv vs 32 μSv). Corresponding underlead doses were similar between operators (median 4 μSv vs 1 μSv). Primary operator height, DSA acquisition time in left anterior oblique (LAO) position, and degrees of LAO angulation were independent predictors of PO head dose.

Because the head is an unprotected area receiving a significant radiation dose during complex TEVAR and the deleterious effects of exposure to this area are not fully understood, vascular interventionists should be cognizant of head exposure increasing with C-arm angulation and limit this maneuver, concluded the investigators.