Patient Radiation Dose in Diagnostic and Interventional Procedures for Intracranial Aneurysms: Experience at a Single Center

Objective

To assess patient radiation doses during cerebral angiography and embolization of intracranial aneurysms in a large sample size from a single center.

Materials and Methods

We studied a sample of 439 diagnostic and 149 therapeutic procedures for intracranial aneurysms in 480 patients (331 females, 149 males; median age, 57 years; range, 21-88 years), which were performed in 2012 with a biplane unit. Parameters including fluoroscopic time, dose-area product (DAP), and total angiographic image frames were obtained and analyzed.

Results

Mean fluoroscopic time, total mean DAP, and total image frames were 12.6 minutes, 136.6 ± 44.8 Gy-cm², and 251 ± 49 frames for diagnostic procedures, 52.9 minutes, 226.0 ± 129.2 Gy-cm², and 241 frames for therapeutic procedures, and 52.2 minutes, 334.5 ± 184.6 Gy-cm², and 408 frames for when both procedures were performed during the same session. The third quartiles for diagnostic reference levels (DRLs) were 14.0, 61.1, and 66.1 minutes for fluoroscopy time, 154.2, 272.8, and 393.8 Gy-cm² for DAP, and 272, 276, and 535 for numbers of image frames in diagnostic, therapeutic, and both procedures in the same session, respectively. The proportions of fluoroscopy in DAP for the procedures were 11.4%, 50.5%, and 36.1%, respectively, for the three groups. The mean DAP for each 3-dimensional rotational angiographic acquisition was 19.2 ± 3.2 Gy-cm². On average, rotational angiography was used 1.4 ± 0.6 times/session (range, 1-4; n = 580).

Conclusion

Radiation dose in our study as measured by DAP, fluoroscopy time and image frames did not differ significantly from other reported DRL studies for cerebral angiography, and DAP was lower with fewer angiographic image frames for embolization. A national registry of radiation-dose data is a necessary next step to refine the dose reference level.