Multicentre comparison of patientand detector dose for X-ray-guided embolisations of arteriovenous malformations in the brain

Abstract

Dosimetric benchmarking at four hospitals was performed to investigate incident entrance dose and dose rate on a phantom, and entrance detector dose and dose rate for protocols that are used in routine clinical practice for complex neuroradiological treatment of arteriovenous malformations (AVMs). Measurements were performed with a head phantom that simulates the attenuation and scattering of the human head for the lateral and posteroanterior (PA) views. For fluoroscopy, the measured incident entrance dose rate and entrance detector dose rate were in the range of 44-172 and 0.3-1.3 μGy s-1, respectively. The pulse rate in fluoroscopy varied between 6.3 and 15 frames per second (fps). For digital subtraction angiography (DSA), incident entrance dose per frame and entrance detector dose per frame were in the range of 744-2800 and 2.6-8.1 μGy/frame, respectively. Optimisation of acquisition parameters such as pulse rate in fluoroscopy, dose per frame in DSA, beam filtration and tube voltage may further improve imaging protocols and lower the patient dose in very complex X-ray-guided embolisations of AVMs in the brain. However, differences in these acquisition parameters observed in this study were relatively small, suggesting that a relatively high degree of optimisation has already been achieved.