Practical techniques for reducing radiation exposure during cerebral angiography procedures

DSA remains the gold standard imaging method for the evaluation of many cerebrovascular disorders, in particular cerebral aneurysms and vascular malformations. The purpose of this study was to demonstrate the effect of modifying DSA frame rate, fluoroscopic and roadmap pulse rates, and flat panel detector (FPD) position on the radiation dose delivered during routine views for a cerebral angiogram in a phantom model.

Adult skull and abdomen/pelvis anthropomorphic phantoms were used to compare the radiation dose metrics Ka,r (in mGy), PKA (in μGym(2)), and fluoroscopy time (in minutes) after modification of fluoroscopic pulses per second (p/s), DSA frames per second (f/s), and FPD position and collimation in three components of a cerebral angiogram: (1) femoral artery access, (2) roadmap guidance, and (3) biplane cerebral DSA.

For femoral artery access, DSA protocols resulted in significantly higher doses than those utilizing fluoroscopy alone (p=0.007). Roadmaps using 3 p/s or 4 p/s delivered significantly less dose than higher pulse rates (p=0.008). The ranges of delivered doses for biplane cerebral DSA were 347.3-1188.5 mGy and 3914.54-9518.78 μGym(2). The lowest radiation doses were generated by the variable frame rate DSA protocols.

Replacing femoral arterial access evaluations by DSA with fluoroscopy, utilizing lower pulse rates during fluoroscopy and roadmap guidance, and choosing variable frame rates for DSA are simple techniques that may be considered by operators in their clinical practices to lower radiation dose during cerebral angiography procedures.