Background And Objectives Several factors such as intracranial aneurysm (IA) morphologic characteristics, location, rupture status, or use of multiple clips have been suggested to predict the risk of incomplete IA clipping. However, the assessment of completeness of IA occlusion has been based on 2-dimensional-digital subtraction angiography, which fails to detect >30% of remnants when compared with 3-dimensional-digital subtraction angiography (3D-DSA) imaging. We aim to identify risk factors for IA remnants after microsurgical clipping based on 3D-DSA imaging. Methods A consecutive series of 329 clipped IAs in 305 patients who underwent 3D-DSA immediately after clipping was evaluated for the presence of IA remnants. Multivariable regression analyses were performed to assess the potential risk factors of IA-related morphologic features, location and rupture status, and number of clips on the odds of remnant presence. Results After clipping 329 IAs, 76 aneurysm remnants were present based on 3D-DSA. Pretreatment IA size was the only robust risk factor associated with the presence of remnants (P < .001). Multivariable regression analysis showed no association between IA rupture status (subarachnoid hemorrhage) (P = .37), IA location (P = .11), use of multiple clips (P = .07), broad-based IAs (P = .38), IA shape (P = .77), or IA calcification (P = .97). Conclusion When assessed by 3D-DSA, the incidence of IA remnants after clipping is higher than reported in the literature. In our series of 3D-DSA based imaging, preoperative IA size was the only robust independent risk factor for incomplete clipping, and these cases must be followed closely.
Grüter et al. (Thu,) studied this question.