Clinical features of ruptured very small intracranial aneurysms (< 3 mm) in patients with subarachnoid hemorrhage

Endovascular Coiling of Ruptured Tiny Saccular Intracranial Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

The safety and efficacy of endovascular coiling of ruptured tiny saccular intracranial aneurysms (IAs) (≤3 mm) remain unknown.

METHODS

A comprehensive search of PubMed, Embase, Web of Science, and Scorpus databases up to November 15, 2023 was performed. Pooled prevalence was calculated for occlusion rates, recanalization, retreatment, long-term favorable outcome, and procedure-related complications and mortality. Pooled odds ratios were calculated to compare these outcomes between coiling and stent-assisted coiling (SAC).

RESULTS

Forty-two studies with 2166 ruptured tiny saccular IAs treated with coiling were included. The follow-up complete aneurysm occlusion rate was 83.9% (95% CI: 77.2-88.9%). The rates of recanalization and retreatment were 7.7% (95% CI: 5.7-10.2%) and 5.8% (95% CI: 4.5-7.5%). The range of median Hunt and Hess grades was 1.4-2.9 and the favorable outcome rate was 85.6% (95% CI: 81.1-89.2%). The rates of thromboembolism, intraprocedural rupture, and mortality were 4.6% (95% CI: 3.6-5.8%), 5.4% (95% CI: 4.1-7.0%), and 5.6% (95% CI: 4.4-7.2%), respectively. Comparison of coiling and SAC revealed no significant difference, except for a higher likelihood of follow-up complete aneurysm occlusion in SAC (odds ratio [OR] 0.37, 95% CI: 0.17-0.80) and recanalization in the coiling (OR, 3.21 [95% CI, 1.37-7.51]).

CONCLUSIONS

Our meta-analysis demonstrates that coiling for ruptured tiny saccular IA is a feasible, effective, and safe approach that is associated with favorable clinical outcomes in both the short and long term for patients with mild to moderate Hunt and Hess grades.

Diagnosis of Unruptured Intracranial Aneurysms Using Proton-Density Magnetic Resonance Angiography: A Comparison With High-Resolution Time-of-Flight Magnetic Resonance Angiography

OBJECTIVE

Differentiating intracranial aneurysms from normal variants using CT angiography (CTA) or MR angiography (MRA) poses significant challenges. This study aimed to evaluate the efficacy of proton-density MRA (PD-MRA) compared to high-resolution time-of-flight MRA (HR-MRA) in diagnosing aneurysms among patients with indeterminate findings on conventional CTA or MRA.

MATERIALS AND METHODS

In this retrospective analysis, we included patients who underwent both PD-MRA and HR-MRA from August 2020 to July 2022 to assess lesions deemed indeterminate on prior conventional CTA or MRA examinations. Three experienced neuroradiologists independently reviewed the lesions using HR-MRA and PD-MRA with reconstructed voxel sizes of 0.253 mm3 or 0.23 mm3, respectively. A neurointerventionist established the gold standard with digital subtraction angiography. We compared the performance of HR-MRA, PD-MRA (0.253-mm3 voxel), and PD-MRA (0.23-mm3 voxel) in diagnosing aneurysms, both per lesion and per patient. The Fleiss kappa statistic was used to calculate inter-reader agreement.

RESULTS

The study involved 109 patients (average age 57.4 ± 11.0 years; male:female ratio, 11:98) with 141 indeterminate lesions. Of these, 78 lesions (55.3%) in 69 patients were confirmed as aneurysms by the reference standard. PD-MRA (0.253-mm3 voxel) exhibited significantly higher per-lesion diagnostic performance compared to HR-MRA across all three readers: sensitivity ranged from 87.2%-91.0% versus 66.7%-70.5%; specificity from 93.7%-96.8% versus 58.7%-68.3%; and accuracy from 90.8%-92.9% versus 63.8%-69.5% (P ≤ 0.003). Furthermore, PD-MRA (0.253-mm3 voxel) demonstrated significantly superior per-patient specificity and accuracy compared to HR-MRA across all evaluators (P ≤ 0.013). The diagnostic accuracy of PD-MRA (0.23-mm3 voxel) surpassed that of HR-MRA and was comparable to PD-MRA (0.253-mm3 voxel). The kappa values for inter-reader agreements were significantly higher in PD-MRA (0.820-0.938) than in HR-MRA (0.447-0.510).

CONCLUSION

PD-MRA outperformed HR-MRA in diagnostic accuracy and demonstrated almost perfect inter-reader consistency in identifying intracranial aneurysms among patients with lesions initially indeterminate on CTA or MRA.

Nomogram model for predicting oculomotor nerve palsy in patients with intracranial aneurysm

AIM

To explore the risk factors of oculomotor nerve palsy (ONP) in patients with intracranial aneurysm (IA) and develop a nomogram model for predicting ONP of IA patients.

METHODS

A total of 329 IA patients were included. Logistic regression analysis was applied to identify independent factors, which were then integrated into the nomogram model. The performance of the nomogram model was evaluated by calibration curve, receiver operating curve (ROC), and decision curve analysis.

RESULTS

Univariate and multivariate logistic regression analysis indicated posterior communicating artery (PCoA) aneurysm [hazard ratio (HR)=17.13, P<0.001] and aneurysm diameter (HR=1.31, P<0.001) were independent risk factors of ONP in IA patients. Based on the results of logistic regression analysis, a nomogram model for predicting the ONP in IA patients was constructed. The calibration curve indicated the nomogram had a good agreement between the predictions and observations. The nomogram showed a high predictive accuracy and discriminative ability with an area under the curve (AUC) of 0.863. The decision curve analysis showed that the nomogram was powerful in the clinical decision. PCoA aneurysm (HR=3.38, P=0.015) was identified to be the only independent risk factor for ONP severity.

CONCLUSION

PCoA aneurysm and aneurysm diameter are independent risk factors of ONP in IA patients. The nomogram established is performed reliably and accurately for predicting ONP. PCoA aneurysm is the only independent risk factor for ONP severity.