The role of microsurgery for poor-grade aneurysmal subarachnoid hemorrhages in the endovascular era

Open surgical treatment of basilar artery aneurysms in the interventional therapy era

PURPOSE

The purpose of this study was to describe the effectiveness and evaluation of open surgical treatment of basilar artery aneurysms in the context of interventional therapy era, including surgical clipping and blood reconstruction, by retrospectively analyzing the clinical data of basilar artery aneurysms in our center.

METHODS

Patients with basilar artery aneurysms who were treated at our center were retrospectively included according to the inclusion and exclusion criteria. The basic clinical data, surgical approach, clinical follow-up and prognosis of the enrolled patients were analyzed in detail. In this study, the mRS score was applied to assess the neurological prognosis of the patients, and the relevant data were statistically analyzed using SPSS.

RESULTS

A total of 104 eligible patients treated at our center from January 2010 to August 2023 were included in this study, of which 67 were treated by open surgery and 37 by bypass. For the 67 patients with open surgical clipping, the mean age was 60.0 (52.0, 65.0) years. The maximum diameter of the aneurysms ranged from 2.0 mm to 54.0 mm, with a mean of 13.9 (10.0, 19.0) mm. The mean follow-up time was 38 (20, 58) months. At the last follow-up, 61 (91.0%) completely obliterated aneurysms and 6 (9.0%) incompletely obliterated aneurysms were found. The prognosis was good in 59 (88.1%) patients and poor in 8 (11.9%). After surgical clipping, the difference between complete and incomplete postoperative aneurysm elimination was statistically significant between the favorable and poor prognosis groups (P < 0.001). For the 37 bypass group patients, the mean age was 52.0 (45.5, 59.0) years. The maximum diameter of the aneurysm ranged from 10.5 mm to 55.0 mm, with a mean of 28.55 ± 12.08 mm. Bypass combined with proximal occlusion was performed in 18 (48.6%) patients, and bypass only was performed in 19 (51.4%) patients. Clinical follow-up was 19.0 (10.5, 43.0) months. There were 19 (51.4%) patients with complete elimination of the aneurysm, 13 (35.1%) with incomplete elimination of the aneurysm, and 5 (13.5%) with aneurysm stabilization. The prognosis was good in 32 (86.5%) patients and poor in 5 (13.5%) patients.

CONCLUSION

Treatment of basilar artery aneurysms is challenging. In the context of the rapidly evolving interventional therapy era, open surgery including surgical clipping and bypass is an ideal option for complex basilar artery aneurysms not amenable to intervention.

Explainable machine learning in outcome prediction of high-grade aneurysmal subarachnoid hemorrhage

OBJECTIVE

Accurate prognostic prediction in patients with high-grade aneruysmal subarachnoid hemorrhage (aSAH) is essential for personalized treatment. In this study, we developed an interpretable prognostic machine learning model for high-grade aSAH patients using SHapley Additive exPlanations (SHAP).

METHODS

A prospective registry cohort of high-grade aSAH patients was collected in one single-center hospital. The endpoint in our study is a 12-month follow-up outcome. The dataset was divided into training and validation sets in a 7:3 ratio. Machine learning algorithms, including Logistic regression model (LR), support vector machine (SVM), random forest (RF), and extreme gradient boosting (XGBoost), were employed to develop a prognostic prediction model for high-grade aSAH. The optimal model was selected for SHAP analysis.

RESULTS

Among the 421 patients, 204 (48.5%) exhibited poor prognosis. The RF model demonstrated superior performance compared to LR (AUC = 0.850, 95% CI: 0.783-0.918), SVM (AUC = 0.862, 95% CI: 0.799-0.926), and XGBoost (AUC = 0.850, 95% CI: 0.783-0.917) with an AUC of 0.867 (95% CI: 0.806-0 .929). Primary prognostic features identified through SHAP analysis included higher World Federation of Neurosurgical Societies (WFNS) grade, higher modified Fisher score (mFS) and advanced age, were found to be associated with 12-month unfavorable outcome, while the treatment of coiling embolization for aSAH drove the prediction towards favorable prognosis. Additionally, the SHAP force plot visualized individual prognosis predictions.

CONCLUSIONS

This study demonstrated the potential of machine learning techniques in prognostic prediction for high-grade aSAH patients. The features identified through SHAP analysis enhance model interpretability and provide guidance for clinical decision-making.

Outcomes following poor-grade aneurysmal subarachnoid haemorrhage: a prospective observational study

BACKGROUND

Up to 35% of aneurysmal subarachnoid haemorrhage (aSAH) cases may present as poor grade, defined as World Federation of Neurosurgical Societies (WFNS) grades IV and V. In this study, we evaluate functional outcomes and prognostic factors.

METHODS

This prospective study included all patients referred to a national, centralized neurosurgical service with a diagnosis of poor-grade aSAH between 01/01/2016 and 31/12/2019. Multivariable logistic regression models were used to estimate probability of poor functional outcomes, defined as a Glasgow Outcome Scale (GOS) of 1-3 at 3 months.

RESULTS

Two hundred fifty-seven patients were referred, of whom 116/257 (45.1%) underwent treatment of an aneurysm, with 97/116 (84%) treated within 48 h of referral. Median age was 62 years (IQR 51-69) with a female predominance (167/257, 65%). Untreated patients tended to be older; 123/141 (87%) had WFNS V, 60/141 (45%) unreactive pupils and 21/141 (16%) circulatory arrest. Of all referred patients, poor outcome occurred in 169/230 (73.5%). Unreactive pupils or circulatory arrest conferred a universally poor prognosis, with mortality in 55/56 (98%) and 19/19 (100%), respectively. The risk of a poor outcome was 14.1% (95% CI 4.5-23.6) higher in WFNS V compared with WFNS IV. Age was important in patients without circulatory arrest or unreactive pupils, with risk of a poor outcome increasing by 1.8% per year (95% CI 1-2.7). In patients undergoing aneurysm securement, 48/101 (47.5%) had a poor outcome, with age, rebleeding, vasospasm and cerebrospinal fluid (CSF) diversion being important prognosticators. The addition of serum markers did not add significant discrimination beyond the clinical presentation.

CONCLUSIONS

The overall outcomes of WFNS IV and V aSAH remain poor, mainly due to the devastating effects of the original haemorrhage. However, in patients selected for aneurysm securement, good outcomes can be achieved in more than half of patients. Age, pre-intervention rebleeding, vasospasm, and CSF diversion are important prognostic factors.

Role of the Subarachnoid Hemorrhage Early Brain Edema Score in the Management of Decompressive Craniectomy for Poor-Grade Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

The Subarachnoid Hemorrhage Early Brain Edema Score (SEBES) is a radiographic marker for early brain injury after aneurysmal subarachnoid hemorrhage (aSAH). We evaluated the role of the SEBES in performing decompressive craniectomy (DC) for poor-grade aSAH.

METHODS

We retrospectively analyzed all cases of poor-grade (World Federation of Neurosurgical Societies [WFNS] grade IV and V) aSAH in adults who underwent microsurgery at our center between April 2017 and March 2021. Patient demographics, clinical presentation, imaging findings, and surgical data were obtained. The study endpoints of DC rate, complications, and functional outcomes (modified Rankin Scale score >3) were compared between the traditional surgery and SEBES-informed groups. A survival analysis was performed to estimate 180-day survival and hazard ratios for death.

RESULTS

The study included 116 patients (mean age, 60.8 ± 9.5 years, DCs [n = 63, 54.3%]). In the univariate analysis, age, intracranial pressure, midline shift, pupil changes, SEBES grade III-IV, traditional group, and WFNS grade Ⅴ were associated with DC. DC (46.4% vs. 67.4%) and in-hospital mortality rates (9.6% vs. 25.6%) were significantly lower in the SEBES-informed group. At day 180 after admission, modified Rankin Scale scores did not significantly differ between the 2 groups, but 180-day survival was significantly higher in the SEBES-informed group (78.1% vs. 53.5%). In the multivariable analysis, age, pupil changes, being in the traditional group, and delayed cerebral ischemia were independently associated with 180-day postadmission mortality.

CONCLUSIONS

The SEBES provides good imaging support for preoperative and intraoperative intracranial pressure management in poor-grade aSAH, allowing for improved DC-related decision-making and better 180-day survival.