Radiation dose and fluoroscopy time of aneurysm coiling in patients with unruptured and ruptured intracranial aneurysms as a function of aneurysm size, location, and patient age

PURPOSE: Endovascular treatment of unruptured intracranial aneurysms (UIAs) requires a risk–benefit analysis and adherence to diagnostic reference levels (DRLs). The national DRL (250 Gy·cm(2)) is only determined for intracranial aneurysm coiling in general, including ruptured intracranial aneurysms (RIAs). This study aims to investigate the dose in the treatment of UIAs and RIAs separately. METHODS: In a retrospective study design, dose area product (DAP) and fluoroscopy time (FT) were assessed for all patients undergoing intracranial aneurysm coiling between 2010 and 2021. DRL was set as the 75th percentile of the dose distribution. A multivariable linear regression analysis was performed to investigate DAP and FT for the two groups, UIA and RIA adjusted for patient age, aneurysm size, and location. RESULTS: 583 (414 females, mean age 56.5 years, 311 UIAs) are included. In the overall population, DAP (median (IQR)) is 157 Gy·cm(2) (108–217) with a median FT of 32.7 min (IQR 24.0–47.0). Local DRL is 183 Gy·cm(2) for UIAs and 246 Gy·cm(2) for RIAs. After adjustment for the other variables, the UIA and RIA groups have a significant effect on both DAP (p < 0.001; 95% CI − 68.432 – − 38.040) and FT (p < 0.001; 95% CI − 628.279 – − 291.254). In general, both DAP and FT increase significantly with patient age and aneurysm size, whereas the location of the aneurysm did not significantly change neither DAP (p = 0.171; 95% CI − 5.537–31.065) nor FT (p = 0.136; 95% CI − 357.391–48.508). CONCLUSION: Both aneurysm size and patient age were associated with increased DAP, whereas aneurysm location did not significantly change DAP or FT. The increased dose in patients with RIAs is likely equivalent to additional diagnostic cerebral four-vessel angiography performed in this group.