Effect of choice of treatment modality on the incidence of shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage

Treatment modality for aneurysmal subarachnoid hemorrhage and risk of shunt dependent hydrocephalus and mortality: population based study

BACKGROUND

Hydrocephalus is a significant contributor to morbidity following aneurysmal subarachnoid hemorrhage (aSAH). We aimed to investigate the association between primary treatment modality and the incidence of hydrocephalus requiring CSF diversion, using a target trial approach for causal inference.

METHODS

This cohort study used US administrative health claims data (Clinformatics Data Mart) and was conducted among aSAH patients undergoing primary treatment with either clipping or coiling, from January 1, 2004, to February 28, 2023. The primary outcome was hydrocephalus requiring CSF diversion surgery while the secondary outcome was mortality. Multivariable regression and 1:1 propensity score (PS) matching were used for confounder control. Crude and adjusted hazard ratios (HRs) with 95% CIs were calculated.

RESULTS

A total of 5816 patients (mean age 59 years; 72% women) undergoing clipping (n=1794) or coiling (n=4022) were included in the primary cohort. The 1:1 PS matched cohort had 1794 participants per arm. Clipping demonstrated higher hazards of shunt dependent hydrocephalus compared with coiling in both the multivariable Fine-Gray model (HR 1.39, 95% CI 1.19 to 1.62) and the PS matched cohorts (HR 1.39, 95% CI 1.16 to 1.66). Mortality analysis favored clipping in the crude analysis (HR 0.78, 95% CI 0.69 to 0.88) but leaned toward coiling after confounder adjustment (HR 1.13, 95% CI 1.00 to 1.29 in the multivariable model; HR 1.11, 95% CI 0.95 to 1.29 in the PS matched cohort).

CONCLUSION

These findings suggest that coiling is associated with reduced hazards of shunt dependent hydrocephalus following aSAH compared with clipping, and provide valuable insights for shared decision making among clinicians and patients, in the context of conflicting evidence from smaller observational studies.

Predicting Shunt Dependency from the Effect of Cerebrospinal Fluid Drainage on Ventricular Size

BACKGROUND

Prolonged external ventricular drainage (EVD) in patients with subarachnoid hemorrhage (SAH) leads to morbidity, whereas early removal can have untoward effects related to recurrent hydrocephalus. A metric to help determine the optimal time for EVD removal or ventriculoperitoneal shunt (VPS) placement would be beneficial in preventing the prolonged, unnecessary use of EVD. This study aimed to identify whether dynamics of cerebrospinal fluid (CSF) biometrics can temporally predict VPS dependency after SAH.

METHODS

This was a retrospective analysis of a prospective, single-center, observational study of patients with aneurysmal SAH who required EVD placement for hydrocephalus. Patients were divided into VPS-dependent (VPS+) and non-VPS dependent groups. We measured the bicaudate index (BCI) on all available computed tomography scans and calculated the change over time (ΔBCI). We analyzed the relationship of ΔBCI with CSF output by using Pearson's correlation. A k-nearest neighbor model of the relationship between ΔBCI and CSF output was computed to classify VPS.

RESULTS

Fifty-eight patients met inclusion criteria. CSF output was significantly higher in the VPS+ group in the 7 days post EVD placement. There was a negative correlation between delta BCI and CSF output in the VPS+ group (negative delta BCI means ventricles become smaller) and a positive correlation in the VPS- group starting from days four to six after EVD placement (p < 0.05). A weighted k-nearest neighbor model for classification had a sensitivity of 0.75, a specificity of 0.70, and an area under the receiver operating characteristic curve of 0.80.

CONCLUSIONS

The correlation of ΔBCI and CSF output is a reliable intraindividual biometric for VPS dependency after SAH as early as days four to six after EVD placement. Our machine learning model leverages this relationship between ΔBCI and cumulative CSF output to predict VPS dependency. Early knowledge of VPS dependency could be studied to reduce EVD duration in many centers (intensive care unit length of stay).

Cerebrospinal fluid predictors of shunt-dependent hydrocephalus after hemorrhagic stroke: a systematic review and meta-analysis

Hydrocephalus is a common complication of hemorrhagic stroke and has been reported to contribute to poor neurological outcomes. Herein, we aimed to investigate the validity of cerebrospinal fluid (CSF) data in predicting shunt-dependent hydrocephalus (SDHC) in patients with hemorrhagic stroke. PubMed, CENTRAL, and Embase databases were searched for relevant studies published through July 31, 2021. The 16 studies with 1505 patient included those in which CSF data predicted risk for SDHC and reports on CSF parameters in patients in whom SDHC or hydrocephalus that was not shunt-dependent developed following hemorrhagic stroke. We appraised the study quality using Newcastle-Ottawa Scale and conducted a meta-analysis of the pooled estimates of the CSF predictors. The meta-analysis revealed three significant CSF predictors for shunt dependency, i.e., higher protein levels (mean difference [MD] = 32.09 mg/dL, 95% confidence interval [CI] = 25.48-38.70, I² = 0%), higher levels of transforming growth factor β1 (TGF-β1; MD = 0.52 ng/mL, 95% CI = 0.42-0.62, I² = 0%), and higher ferritin levels (MD = 108.87 µg/dL, 95% CI = 56.68-161.16, I² = 36%). The red blood cell count, lactate level, and glucose level in CSF were not significant in predicting SDHC in patients with hemorrhagic stroke. Therefore, higher protein, TGF-β1, and ferritin levels in CSF are significant predictors for SDHC in patients with hemorrhagic stroke. Measuring these CSF parameters would help in the early recognition of SDHC risk in clinical care.

Clipping versus coiling for aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis of prospective studies

Neurosurgical clipping and endovascular coiling are both standard therapies to prevent rebleeding after aneurysmal subarachnoid hemorrhage (aSAH). However, controversy still exists about which is the optimal treatment. This meta-analysis aims to assess the effectiveness and safety of two treatments with high-quality evidence. Web of Science, Cochrane Library, EMBASE, Pubmed, Sinomed, China National Knowledge Infrastructure, and Wanfang Data databases were systematically searched on August 5, 2021. Randomized controlled trials (RCTs) and prospective cohort studies that evaluated the effectiveness and safety of clipping versus coiling in aSAH patients at discharge or within 1-year follow-up period were eligible. No restriction was set on the publication date. Meta-analyses were conducted to calculate the pooled estimates and 95% confidence intervals (CI) of relative risk (RR). Eight RCTs and 20 prospective cohort studies were identified. Compared to coiling, clipping was associated with a lower rebleeding rate at discharge (RR: 0.52, 95% CI: 0.29––0.94) and a higher aneurysmal occlusion rate (RR: 1.33, 95% CI: 1.19–1.48) at 1-year follow-up. In contrast, coiling reduced the vasospasm rate at discharge (RR: 1.45, 95% CI: 1.23–1.71) and 1-year poor outcome rate (RR: 1.27, 95% CI: 1.16–1.39). Subgroup analyses presented that among patients with a poor neurological condition at admission, no statistically significant outcome difference existed between the two treatments. The overall prognosis was better among patients who received coiling, but this advantage was not significant among patients with a poor neurological condition at admission. Therefore, the selection of treatment modality for aSAH patients should be considered comprehensively.

The Pathogenesis of Hydrocephalus Following Aneurysmal Subarachnoid Hemorrhage

Hydrocephalus is a common complication of aneurysmal subarachnoid hemorrhage (aSAH) and reportedly contributes to poor neurological outcomes. In this review, we summarize the molecular and cellular mechanisms involved in the pathogenesis of hydrocephalus following aSAH and summarize its treatment strategies. Various mechanisms have been implicated for the development of chronic hydrocephalus following aSAH, including alterations in cerebral spinal fluid (CSF) dynamics, obstruction of the arachnoid granulations by blood products, and adhesions within the ventricular system. Regarding molecular mechanisms that cause chronic hydrocephalus following aSAH, we carried out an extensive review of animal studies and clinical trials about the transforming growth factor-β/SMAD signaling pathway, upregulation of tenascin-C, inflammation-dependent hypersecretion of CSF, systemic inflammatory response syndrome, and immune dysregulation. To identify the ideal treatment strategy, we discuss the predictive factors of shunt-dependent hydrocephalus between surgical clipping and endovascular coiling groups. The efficacy and safety of other surgical interventions including the endoscopic removal of an intraventricular hemorrhage, placement of an external ventricular drain, the use of intraventricular or cisternal fibrinolysis, and an endoscopic third ventriculostomy on shunt dependency following aSAH were also assessed. However, the optimal treatment is still controversial, and it necessitates further investigations. A better understanding of the pathogenesis of acute and chronic hydrocephalus following aSAH would facilitate the development of treatments and improve the outcome.

Efficacy of translamina terminalis ventriculostomy tube in prevention of chronic hydrocephalus after aneurysmal subarachnoid hemorrhage

Background

Chronic shunt-dependent hydrocephalus is still a common complication after aneurysmal SAH (aSAH) and is associated with increased morbidity. Pathology of chronic shunt-dependent hydrocephalus after aSAH is complex and multifactorial which makes its prevention challenging. We thought to evaluate whether external ventricular drainage (EVD) through fenestrated lamina terminalis would decrease the rate of chronic shunt-dependent hydrocephalus after aSAH.

Methods

A retrospective analysis of 68 consecutive patients with aSAH who underwent microsurgical clipping of the ruptured aneurysm. Patients were divided into two groups: Group A included patients with lamina terminalis fenestration without insertion of ventriculostomy tube and Group B included patients with EVD through fenestrated lamina terminalis. Demographic, clinical, radiological, and outcome variables were compared between groups.

Results

Group A comprised 29 patients with mean age of 47.8 years and Group B comprised 39 patients with mean age of 46.6 years. Group B patients had statistically significant (P < 0.05) lower incidence of chronic shunt- dependent hydrocephalus than Group A patients (30.8% vs. 55.2%, respectively).

Conclusion

EVD through fenestrated lamina terminalis is safe and may be effective in decreasing the incidence of chronic shunt-dependent hydrocephalus after aSAH.

Shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage

INTRODUCTION

Shunt-dependent hydrocephalus (SDHC) after aneurysmal subarachnoid hemorrhage (aSAH) is the occurrence of symptomatic ventriculomegaly requiring permanent shunt diversion. Although several studies investigated the predictors of SDHC, the role of many of these factors, as well as the prevalence of SDHC and patients' clinical outcome, remain a matter of controversy.

EVIDENCE ACQUISITION

According to PRISMA guidelines we performed a systematic search looking into four databases with the purpose of clarifying the prevalence of SDHC after aSAH, the predictors of SDHC, the mortality rate and clinical outcome of patients with and without SDHC.

EVIDENCE SYNTHESIS

Our analysis included 23 studies involving 22,264 patients. The overall prevalence of SDHC was 22.3% (95% CI: 17.9-26.6%). The predictors of SDHC included radiological hydrocephalus at presentation (OR 6.3, 95% CI: 2.27-17.51%), external ventricular drainage insertion (OR 5.7, 95% CI: 3.77-8.61%), high Hunt and Hess scale score (HHS 3-5: OR 3.3, 95% CI: 2.64-4.15%; HHS 4-5: OR 3.2, 95% CI: 2.4-4.2%), high Fisher grade (OR 3.1, 95% CI: 2.58-3.72%), intraventricular blood (OR 3.1, 95% CI: 2.60-3.71%), vasospasm (OR 1.9, 95% CI: 1.30-2.81%), intraparenchymal hemorrhage (OR 1.8, 95% CI: 1.2-2.78%), female gender (OR 1.3, 95% CI: 1.14-1.65%) and posterior circulation aneurysms (OR 1.4, 95% CI: 1.11-1.71%). The modality of aneurysm repair did not affect the rate of permanent shunt diversion. Patients with SDHC were more likely to be associated with a poor clinical outcome (mRS 3-6) (OR 4.3), even if mortality rate was similar between shunted and non-shunted patients (9%, 95% CI: 2-16% vs. 10.8%, 95% CI: 3.2-18.5%) (P=0.09).

CONCLUSIONS

The prevalence of SDHC is 22.3%. Our analysis identified several predictors of SDHC that can assist clinicians in monitoring patients with an aSAH. Shunt dependency is not related to the treatment modality of the ruptured aneurysm, whereas the occurrence of SDHC is a predictor of poor clinical outcome.