Segmental location and multiple-clip reconstruction in middle cerebral artery aneurysm surgery: a retrospective cohort

Abstract Background Segmental location changes the arterial and branch relationships encountered during middle cerebral artery (MCA) aneurysm clipping, but its ability to anticipate a multiple-clip construct is uncertain. This study evaluated the association between aneurysm segmental location and multiple-clip reconstruction. Methods This retrospective single-center cohort screened 107 adults who underwent microsurgical clipping of MCA aneurysms. The location analysis included 86 operations with recorded segmental location. The primary exposure compared bifurcation-involving aneurysms with proximal or distal M1 aneurysms. Multiple-clip reconstruction was operationally defined as use of at least two documented permanent clips. Exact tests and logistic regression adjusted for aneurysm size category and the presence of multiple aneurysms were used. Results The cohort included 62 bifurcation-involving and 24 M1-segment aneurysms. Multiple-clip reconstruction was used in 31/86 operations (36.0%): 21/62 bifurcation-involving cases (33.9%) and 10/24 M1-segment cases (41.7%; exact odds ratio 0.72, 95% confidence interval 0.25–2.14; p = 0.618). Segmental location was not independently associated with the outcome after adjustment (adjusted odds ratio 0.61, 95% confidence interval 0.22–1.73; p = 0.351). Non-small aneurysm category was independently associated with multiple-clip reconstruction (adjusted odds ratio 5.99, 95% confidence interval 1.93–18.56; p = 0.002). Four-category and sensitivity analyses were concordant. Conclusions Multiple-clip reconstruction occurred across all recorded MCA segmental locations. Segmental location alone did not identify operations requiring multiple clips, whereas recorded aneurysm size category provided stronger information. Location should therefore be integrated with lesion morphology rather than used as a stand-alone marker of clip-construct complexity.