Posterior communicating artery aneurysm(PCoAA) exhibit complex anatomical relationships, and microsurgical clipping of large or posteromedially projecting aneurysms remains technically challenging with considerable postoperative morbidity. Therefore, selecting optimal surgical approach has become a key clinical concern. This study compares the efficacy, safety, and overall performance of the Dolenc approach versus the conventional pterional approach for clipping large or posteromedially projecting PCoA aneurysms.

A prospective nonrandomized controlled study design was adopted. A total of 79 patients with large or posteromedially projecting PCoA aneurysms consecutively treated in Department of Neurosurgery, Liangping Hospital of the First Affiliated Hospital of Chongqing Medical University between September 2019 and September 2025 were enrolled, and alternatively assigned to the Dolenc approach group (n=41) or conventional pterional approach group (n=38) based on admission sequence. The primary endpoint was the favorable outcome rate at 3 months postoperatively, assessed using Glasgow Outcome Scale (GOS), with GOS score of 4 to 5 defined as a favorable outcome and score of 1 to 3 as an unfavorable outcome. Secondary endpoints included operative time, postoperative length of hospital stay, distribution of GOS scores, and aneurysm neck residual on digital subtraction angiography (DSA)/CT angiography (CTA) at 3 months postoperatively (defined as contrast filling of the aneurysm neck). Firth’s bias-reduced penalized likelihood logistic regression analysis was used to evaluate the association between surgical approach and unfavorable outcome (with age stratification as covariate), reporting odds ratio (OR), 95% confidence interval (CI), and P value. In addition, a standardized three-domain (technical-safety-efficiency) scoring system and a composite score were constructed for descriptive comparison, along with cost-effectiveness and subgroup analyses.

For the primary endpoint, the favorable outcome rate was 97.6% (40/41) in the Dolenc group and 78.9% (30/38) in the conventional group, with an absolute difference of 18.6% (95%CI: 4.8% to 32.4%, P=0.009). Postoperative length of hospital stay was shorter in the Dolenc group (13.46±2.43 vs 16.05±2.46 d), with a mean difference of -2.59 d (95%CI: -3.69 to -1.49, P<0.001). Operative time was comparable between groups (3.98±0.60 vs 3.97±0.62 h), with a mean difference of 0.01 h (95%CI: -0.26 to -0.28, P=0.944). Regarding functional outcomes, the Dolenc group had a greater proportion of patients achieving a GOS score of 5 than the conventional group (61.0% vs 18.4%), with an absolute difference of 42.6% (95%CI: 23.2% to 61.9%, P<0.001), and the distribution of GOS scores in the Dolenc group was shifted toward better outcomes, with lower proportions of patients having GOS scores of 4 and 3 than the conventional pterional group (χ²=14.96, P<0.001). For imaging follow-up, the neck remnant rate was lower in the Dolenc group (2.4% vs 13.2%), with an absolute difference of -10.8% (95%CI: -22.5% to -1.0%, P=0.072). Multivariable analysis showed that the conventional pterional approach was associated with unfavorable outcome (OR=10.20, 95%CI: 1.20 to 87.04, P=0.034). The model was significant overall (χ²=7.56, df=2, P=0.02), with good calibration (Hosmer-Lemeshow test P=0.82), and moderate discrimination (AUC=0.75, 95%CI: 0.61 to 0.86). Both the three-domain scores and the composite score were higher in the Dolenc group (composite score: 0.873 vs 0.739). Subgroup analyses suggested the Dolenc approach demonstrated greater advantage in high-risk/complex subgroups, with difference of 0.256 for Hunt-Hess grade Ⅲ-Ⅳ (95%CI: 0.056 to 0.475, P=0.025) and 0.157 for large aneurysms (95%CI: 0.016 to 0.305, P=0.049); however, these findings should be interpreted with caution given the limited sample sizes in some subgroups.

In this cohort, for microsurgical clipping of large or posteromedially projecting PCoA aneurysms, the Dolenc approach is associated with a higher rate of 3-month favorable postoperative outcomes and a shorter length of hospital stay, without an apparent increase in operative time.