Risk factors for ruptured intracranial aneurysms

Systematic Review of Radiomics and Artificial Intelligence in Intracranial Aneurysm Management

Intracranial aneurysms, with an annual incidence of 2%-3%, reflect a rare disease associated with significant mortality and morbidity risks when ruptured. Early detection, risk stratification of high-risk subgroups, and prediction of patient outcomes are important to treatment. Radiomics is an emerging field using the quantification of medical imaging to identify parameters beyond traditional radiology interpretation that may offer diagnostic or prognostic significance. The general radiomic workflow involves image normalization and segmentation, feature extraction, feature selection or dimensional reduction, training of a predictive model, and validation of the said model. Artificial intelligence (AI) techniques have shown increasing interest in applications toward vascular pathologies, with some commercially successful software including AiDoc, RapidAI, and Viz.AI, as well as the more recent Viz Aneurysm. We performed a systematic review of 684 articles and identified 84 articles exploring the applications of radiomics and AI in aneurysm treatment. Most studies were published between 2018 and 2024, with over half of articles in 2022 and 2023. Studies included categories such as aneurysm diagnosis (25.0%), rupture risk prediction (50.0%), growth rate prediction (4.8%), hemodynamic assessment (2.4%), clinical outcome prediction (11.9%), and occlusion or stenosis assessment (6.0%). Studies utilized molecular data (2.4%), radiologic data alone (51.2%), clinical data alone (28.6%), and combined radiologic and clinical data (17.9%). These results demonstrate the current status of this emerging and exciting field. An increased pace of innovation in this space is likely with the expansion of clinical applications of radiomics and AI in multiple vascular pathologies.

Identification of Key Risk Factors for Rupture in Small Intracranial Aneurysms: A Multicenter Study

BACKGROUND

Predicting rupture risk in small intracranial aneurysms (IAs) < 5 mm is crucial for guiding clinical decisions. This study aims to identify key clinical and morphological risk factors associated with rupture in small IAs, providing better insight for decision-making.

METHODS

A retrospective analysis was performed on patients with small IAs from one center, with external validation data from another center. Logistic regression identified significant risk factors for aneurysm rupture, which were incorporated into a predictive model. The model's performance was evaluated using the area under the receiver operating characteristic curve, calibration plots, and the Hosmer-Lemeshow goodness-of-fit test. Clinical utility was assessed via decision curve analysis.

RESULTS

The training cohort consisted of 226 patients (ruptured, n = 181; unruptured, n = 92), while 136 patients (ruptured, n = 100; unruptured, n = 59) were used for external validation. Significant risk factors included hypertension, smoking, anterior communicating artery aneurysms, daughter sacs, aspect ratio, and size ratio. The model demonstrated strong predictive ability with area under the curves of 0.969 and 0.967 in the training and validation cohorts, respectively. Calibration plots indicated a good agreement between predicted and observed rupture risks, while decision curve analysis highlighted the model's clinical relevance.

CONCLUSION

This study identifies and validates critical risk factors associated with small IA rupture and presents a clinically useful, high-accuracy predictive model to aid in individualized patient management.

Risk factors of cerebral aneurysms rupture in an Indonesian population

BACKGROUND

The demographic, clinical, and angiographic features of ruptured aneurysms compared to unruptured cerebral aneurysms in Indonesia are still limited. This study aims to determine risk factors for rupture according to clinical patterns and morphological features in the Indonesian population.

METHOD

We retrospectively reviewed all cerebral aneurysm registries at the largest comprehensive stroke center in Indonesia from January 2019 to January 2022. We compared demographic and vascular risk factors as well as angiographic features between patients with ruptured and unruptured aneurysms with univariate and multivariate analyses.

RESULTS

Of 275 patients, 231 (84%) had ruptured cerebral aneurysms. We found a significant difference between the ruptured and unruptured groups in variables such as age, hypertension, dyslipidemia, smoking, location, and type of aneurysm. It was found that only the anterior circulation site (OR 4.91, 95% CI 1.47-16.48; p < 0.01) and saccular type (OR 5.45, 95% CI 1.42-20.93; p = 0.01) were significantly linked to ruptured aneurysms.

CONCLUSION

Our findings revealed that anterior location and saccular type were substantially linked with ruptured aneurysms in the Indonesian population.

The rupture of an anterior communicating artery aneurysm does not associate with an asymmetry in the A1 or A2 arteries: a retrospective study of radiological features

BACKGROUND AND OBJECTIVES

Although the formation and rupture risk of an anterior communicating artery (ACoA) aneurysm has been the subject of many studies, no previous study has primarily searched for the relationship of the parent and daughter vessels and the impact of their size/diameter ratio on the potential rupture risk of an AcoA aneurysm. The objective of this study is to explore this link and to further analyse the surrounding vasculature of the anterior communicating artery aneurysm.

MATERIALS AND METHODS

We conducted a retrospective analysis of 434 patients: 284 patients with an ACoA aneurysm (121 unruptured and 162 ruptured) and 150 control patients without an ΑCoA aneurysm. Radiological angiography investigations were used to assess the diameter ratios of the parent vessels in addition to ACoA aneurysm morphology parameters.

RESULTS

When comparing the ruptured to the unruptured cases, we observed no significant difference in the parent or daughter vessel diameter ratios. Younger patient age (OR 0.96, p = 0.00) and a higher aneurysm size ratio (OR 1.10, p = 0.02) were of prognostic importance concerning the rupture risk of the aneurysm. The A1 diameter ratio and the A2 diameter were not statistically significant (OR 1.00, p = 0.99, and OR 3.38, p = 0.25 respectively).

CONCLUSIONS

In our study, we focused on asymmetry in the parent and daughter vessels as well as traditional ACoA aneurysm morphological characteristics. We were able to label younger patient age and a greater size ratio as independent prognostic factors for ACoA aneurysm rupture. We were unable to label parent and daughter vessel asymmetry as prognostic factors. To validate our findings, parent and daughter vessel asymmetry should be subjected to future prospective studies.

Unruptured intracranial aneurysms: Why should we focus on small aneurysms? A comprehensive update of recent findings

Intracranial aneurysms (IAs) are a significant public health concern because they have the potential to cause deva-stating consequences, including death and disability. Despite advances in diagnostic and treatment modalities, the outcomes for patients with aneurysmal subarachnoid haemorrhage (aSAH) remain poor, with high rates of rebleeding, vasospasm, and cerebral ischaemia. IAs are a significant risk factor for aSAH, and it is estimated that up to 3% of the general population have IAs. Recent studies using novel imaging modalities have shown that the prevalence of IAs may be much higher, with 6.6% of adults aged 40-84 years having intradural saccular IAs ≥ 2 mm. The risk of rupture for IAs is difficult to predict, and the decision to treat them invasively is based on a balance between the estimated rupture risk and the procedural risks of the treatment. However, the mortality and morbidity rates among patients treated for IAs can be as high as 5%. There is a need for clear guidelines on the treatment of IAs, and this review aims to provide an update on recent findings in this area. To achieve this goal, the authors identified and summarized recent, high-impact studies on IAs. The review focuses on the diagnostic and treatment options for IAs, as well as the risks associated with these interventions. The authors also provide an overview of the natural history of IAs and discuss the challenges and uncertainties in managing these patients.

Intracranial aneurysm rupture risk in northern China: a retrospective case-control study

Background

Rupture of intracranial aneurysms (IAs) can cause subarachnoid hemorrhage (SAH), which leads to severe neurological dysfunction and even death. Exploring the risk factors for IA rupture and taking preventive measures accordingly can reduce or prevent the occurrence of SAH. Currently, there is still no consensus on the detrimental factors for IA rupture. Thus, our study aimed to investigate the risk factors of IA rupture in a population of northern China.

Methods

We systematically collected the demographic features, medical history, and imaging data of aneurysms from patients with ruptured and unruptured IAs (UIAs) who attended the Department of Neurosurgery at the Second Hospital of Hebei Medical University from 2014 to 2019. All cases had been diagnosed by digital subtraction angiography. We excluded patients with SAH resulting from injuries, as well as those with vascular dissection and incomplete data. Finally, 1,214 patients including 616 with ruptured IAs and 598 with UIAs were collected for further analysis. A case-control study was conducted, in which multivariable logistic regression was used to analyze the risk factors for IA rupture.

Results

Our multivariable logistic regression showed that anterior cerebral artery [odds ratio (OR) =2.413; 95% confidence interval (CI): 1.235-4.718], anterior communicating artery (OR =3.952; 95% CI: 2.601-6.006), posterior communicating artery (OR =2.385; 95% CI: 1.790-3.177), and anterior circulation branches (OR =3.493; 95% CI: 1.422-8.581) were risk factors for IA rupture, whereas patients with a history of cerebral infarction (OR =0.395; 95% CI: 0.247-0.631) and those with IAs located in the internal carotid artery (OR =0.403; 95% CI: 0.292-0.557) were less likely to have IA rupture.

Conclusions

IAs at specific locations are prone to rupture. These IAs should be paid particular attention and preventive measures should be taken to reduce or prevent their rupture.

Integrate prediction of machine learning for single ACoA rupture risk: a multicenter retrospective analysis

Background

Statistically, Anterior communicating aneurysm (ACoA) accounts for 30 to 35% of intracranial aneurysms. ACoA, once ruptured, will have an acute onset and cause severe neurological dysfunction and even death. Therefore, clinical analysis of risk factors related to ACoA and the establishment of prediction model are the benefits to the primary prevention of ACoA.

Methods

Among 1,436 cases of single ACoA patients, we screened 1,325 valid cases, classified risk factors of 1,124 cases in the ruptured group and 201 cases in the unruptured group, and assessed the risk factors, respectively, and predicted the risk of single ACoA rupture by using the logistic regression and the machine learning.

Results

In the ruptured group (84.8%) of 1,124 cases and the unruptured group (15.2%) of 201 cases, the multivariable logistic regression (MLR) model shows hemorrhagic stroke history (OR 95%CI, p:0.233 (0.120-0.454),<0.001) and the age stratification of 60-69 years (OR 95%CI, p:0.425 (0.271-0.668),<0.001) has a significant statistic difference. In the RandomForest (RF) model, hemorrhagic stroke history and age are the best predictive factors.

Conclusion

We combined the analysis of MLR, RF, and PCA models to conclude that hemorrhagic stroke history and gender affect single ACoA rupture. The RF model with web dynamic nomogram, allows for real-time personalized analysis based on different patients' conditions, which is a tremendous advantage for the primary prevention of single ACoA rupture.

Clinical trial registration

https://www.chictr.org.cn/showproj.html?proj=178501.

The role of MicroRNA as a potential diagnostic and prognostic biomarker for cerebral aneurysms

OBJECTIVES

To identify the dysregulated functional miRNAs, miRNA-16, miRNA-143, and miRNA-200 as potential biomarkers of cerebral aneurysms(CAs) to aid in diagnosis and prognosis.

METHODS

This is a prospective case-control study conducted among patients with CA. All patients' computed tomography angiography (CTA) and interventional angiogram were assessed and studied. The miRNAs were isolated and quantified from peripheral blood samples and the expression profiling was done using TaqMan chemistry on Real-Time PCR.

RESULTS

A total of 37 samples were included. Three cases had double aneurysms and 10 cases presented with aneurysmal rupture. miRNA-16, miRNA-143, and miRNA-200 were upregulated with an absolute fold-change of >8 in the CA group in comparison to controls (p<0.05). miRNA-200 showed double expression in patients with single aneurysm. A statically significant increase was observed in the expression of miRNA-143 in patients who had an aneurysmal rupture with p<0.05. Diabetic patients showed an obvious increase in miRNA-200 (13.03 folds) and miRNA-16 (26.82 folds) expression. Also, there was a notable elevation in miRNA-16, miRNA-143, and miRNA-200 in patients who had hypertension in comparison to those who did not.

CONCLUSION

miRNA-16, miRNA-143, and miRNA-200 showed statically significant higher expression among cases with cerebral aneurysms in comparison to controls. Thus, these preliminary results of miRNAs biomarkers are promising future tool to be used for aneurysmal screening.

Scar Epilepsy as a Complication of Subarachnoid Hemorrhage in a Patient With Adult Polycystic Kidney Disease: A Case Report

Polycystic kidney disease (PKD) is the most common hereditary disorder of kidneys. In adults, PKD1 gene mutation almost always signifies its subtype, autosomal dominant polycystic kidney disease (ADPKD), or adult polycystic kidney disease. ADPKD is a multisystemic disorder giving rise to renal and extra-renal manifestations. The renal shutdown is the most feared renal complication while the development of intracranial aneurysms is considered the most lethal extra-renal feature. This can be attributed to the increased risk of rupture associated with aneurysms leading to a condition called subarachnoid hemorrhage (SAH). While being notorious for the subtle situations SAH often leads to, its association with the onset of seizures is a matter of high clinical significance. We present a patient with a kidney disorder (ADPKD) that has led to the onset of epilepsy. Five years after the diagnosis of ADPKD, he developed an aneurysm in the right internal carotid artery, for which he was treated conservatively. After four months, he presented with the onset of symptoms of SAH, which was confirmed by computed tomography angiography. Clipping was unable to be performed, and the patient was treated conservatively, this time as well. Recently, the patient presented with the onset of generalized tonic-clonic seizures, unable to be controlled with single anti-epileptics. He was stabilized by dual intravenous antiepileptics but on further workup, he was found to have a recurrence of a berry aneurysm for which he was referred to a neurosurgeon for a clipping procedure to be performed. The operation was successful, but the patient was still found to be an epileptic for which he was discharged with a long-term course of double anti-epileptics.

A comparison of endovascular coil systems for the treatment of small intracranial aneurysms

BACKGROUND

Endovascular coiling of small, intracranial aneurysms remains controversial and difficult, despite advances in technology.

METHODS

We retrospectively reviewed data for 62 small aneurysms (<3.99 mm) in 59 patients. Occlusion rates, complications rates, and coil packing densities were compared between subgroups based upon coil type and rupture status.

RESULTS

Ruptured aneurysms predominated (67.7%). Aneurysms measured 2.99 ± 0.63 mm by 2.51 ± 0.61 mm with an aspect ratio of 1.21 ± 0.34 mm. Brands included Optima (Balt) (29%), MicroVention Hydrogel (24.2%), and Penumbra SMART (19.4%) coil systems. Average packing density was 34.3 ± 13.5 mm³. Occlusion rate was 100% in unruptured aneurysms; 84% utilized adjuvant devices. For ruptured aneurysms, complete occlusion or stable neck remnant was achieved in 88.6% while recanalization occurred in 11.4%. No rebleeding occurred. Average packing density (p = 0.919) and coil type (p = 0.056) did not impact occlusion. Aspect ratio was smaller in aneurysms with technical complications (p = 0.281), and aneurysm volume was significantly smaller in those with coil protrusion (p = 0.018). Complication rates did not differ between ruptured and unruptured aneurysms (22.6 vs. 15.8%, p = 0.308) or coil types (p = 0.830).

CONCLUSION

Despite advances in embolization devices, coiling of small intracranial aneurysms is still scrutinized. High occlusion rates are achievable, especially in unruptured aneurysms, with coil type and packing density suggesting association with complete occlusion. Technical complications may be influenced by aneurysm geometry. Advances in endovascular technologies have revolutionized small aneurysm treatment, with this series demonstrating excellent aneurysm occlusion especially in unruptured aneurysms.

Volume of Aneurysmal Subarachnoid Hematoma Measured Quantitatively by 3D Slicer to Predict Symptomatic Cerebral Vasospasm

BACKGROUND AND OBJECTIVES

Aneurysmal subarachnoid hemorrhage is strongly associated with symptomatic cerebral vasospasm. This study aims to investigate whether a quantitative measure of aneurysmal subarachnoid hematoma by 3D Slicer is more valuable for vasospasm risk prediction compared with modified Fisher scale and the new scale by Eagles.

MATERIALS AND METHODS

We performed a retrospective research of Digital Imaging and Communications in Medicine format (DICOM) in aneurysmal patients treated at our institution from 2019 to 2020. Association between vasospasm and hematoma volume by 3D Slicer was explored by univariate and multivariate analyses. Value of risk prediction was compared through area under the receiver operator characteristic curve (AUC) among the modified Fisher scale, the new scale by Eagles, and hematoma volume by 3D Slicer.

RESULTS

Hematoma volume by 3D Slicer had a significant relationship with vasospasm both by one-way analysis of variance (ANOVA; F = 19.37, P < 0.001) and a binary logistic regression analysis (odds ratio [OR] = 1.05, P = 0.016). Hematoma volume by 3D Slicer had a significantly higher AUC (0.708; 95% confidence interval [CI]: 0.618-0.798, P < 0.001) than the modified Fisher scale and the new scale by Eagles. The optimal diagnostic threshold for hematoma volume by 3D Slicer was 15.98 ml, and the sensitivity and specificity were 73.5% and 58.6%, respectively.

CONCLUSIONS

Volume of aneurysmal subarachnoid hematoma measured quantitatively by 3D Slicer can improve the predictive value for symptomatic cerebral vasospasm.

Sex differences and risk factors for bleeding in Alagille syndrome

Spontaneous bleeds are a leading cause of death in the pediatric JAG1-related liver disease Alagille syndrome (ALGS). We asked whether there are sex differences in bleeding events in patients, whether Jag1Ndr/Ndr mice display bleeds or vascular defects, and whether discovered vascular pathology can be confirmed in patients non-invasively. We performed a systematic review of patients with ALGS and vascular events following PRISMA guidelines, in the context of patient sex, and found significantly more girls than boys reported with spontaneous intracranial hemorrhage. We investigated vascular development, homeostasis, and bleeding in Jag1Ndr/Ndr mice, using retina as a model. Jag1Ndr/Ndr mice displayed sporadic brain bleeds, a thin skull, tortuous blood vessels, sparse arterial smooth muscle cell coverage in multiple organs, which could be aggravated by hypertension, and sex-specific venous defects. Importantly, we demonstrated that retinographs from patients display similar characteristics with significantly increased vascular tortuosity. In conclusion, there are clinically important sex differences in vascular disease in ALGS, and retinography allows non-invasive vascular analysis in patients. Finally, Jag1Ndr/Ndr mice represent a new model for vascular compromise in ALGS.

Outcome of Cerebral Aneurysm Clipping in Nigeria: A Single-Centre Experience

Background

Ruptured cerebral artery aneurysms (RCAA) are devastating diseases with high morbidity and mortality rates if not promptly managed. In Nigeria, access to timely neurosurgical services remains a challenge and aneurysm coiling is still not possible in virtually all centres in Nigeria. The aim of this study is to report on our 9 years' experience with clipping of cerebral aneurysm and on the attendant clinical outcomes.

Methodology

A retrospective analysis of all consecutive operated RCAA between March 2012 and June 2021 was conducted. Patients' demographic parameters, World Federation of Neurosurgical Societies (WFNS) grade, Hunt and Hess (HH) grade, aneurysm location, timing of surgery and outcome were analysed. Outcome was measured using Glasgow Outcome Scale (GOS) score.

Results

A total 29 were included in the study. The most common age group affected was between 50-59 years. RCAA were mainly in the region of the middle cerebral artery and posterior communicating artery (PComA) territories. All the patients presented after 24 hours of the ictus. Two (6.9%) patients had multiple aneurysms. Early clipping (<72hours after presentation) was possible in 8 (27.6%) patients. At least one episode of a rebleed occurred in 19 (65.5%) patients prior to surgery. Mortality rate was 17.2%. None of the patients with PComA aneurysm died. The patients' pre-operative WFNS and HH grades were significantly associated with GOS.

Conclusion

Modifiable factors like under diagnoses, delayed referral, cultural belief and financial challenges may account for the low number of patients presenting for neurosurgical care. The possibility of a sizeable number of patients dying due to these factors is a strong possibility for the low number of patients presenting for neurosurgical care.

U-Shaped Association of Aspect Ratio and Single Intracranial Aneurysm Rupture in Chinese Patients: A Cross-Sectional Study

Background: Previous studies have analyzed the association of aspect ratio (AR) on the ruptured intracranial aneurysm (IA), but the findings are inconclusive and controversial. Therefore, the study aimed to derive a more detailed estimation of this association between AR and ruptured IA in Chinese IA patients. Methods: The present work was a cross-sectional study. We retrospectively collected 1,588 Chinese patients with a single IA from January 2010 to November 2017. The relationship was examined between AR at diagnosis and ruptured IA. Covariates included data of demographics, morphological parameters, lifestyle habits, clinical features, and comorbidities. Binary logistic regression and two-piecewise linear models were used to analyze independent associations of AR with ruptured IA. Results: The results suggest that the association between AR and IA rupture was U-shaped. In the AR range of 1.08-1.99, the prevalence of IA rupture was 13% lower for each 0.1-unit increment in AR [odds ratio 0.87, 95% confidence interval (CI) 0.80-0.98]. Conversely, for every 0.1-unit increase in AR, the prevalence of IA rupture increased by ~3% (odds ratio 1.03, 95% CI 1.01-1.06) in the AR range of 3.42-4.08. Conclusion: The relationship between AR and ruptured IA was U-shaped, with the negative association at AR of 1.08-1.99 and positive association at AR of 3.42-4.08.

Electroconvulsive Therapy in Elderly Patients With Cerebral Aneurysms: A Systematic Review With Clinical Recommendations

INTRODUCTION

Electroconvulsive therapy (ECT) is commonly used in the elderly due to its proven efficacy and safety profile. However, presence of cardiovascular comorbidities such as cerebral aneurysms may complicate the course of treatment. Our knowledge about the possible risk factors and precautionary measures remains limited.

METHODS

We performed a systematic review of published case reports of elderly patients with cerebral aneurysms treated with ECT.

RESULTS

A total of 11 cases were included for the review. One patient died because of subarachnoid hemorrhage (SAH) secondary to ictal hypertensive surge during treatment with ECT.

DISCUSSION

Risk factors such as history of hypertension, age of the patient, extent of the ictal surge in blood pressure, efficacy of prophylactic treatment to control surge in blood pressure and characteristics of cerebral aneurysm each elevated the risk of complication in these cases. We reviewed safety measures based on the evidence from the current literature available.

CONCLUSION

ECT is safe in elderly patients with cerebral aneurysms provided appropriate safety measures are employed. Screening for cerebral aneurysms in high risk patients, effective prevention and management of blood pressure elevation acutely during ECT is the best practice to avoid adverse outcomes.

Diabetes is not protective against the formation of unruptured cerebral aneurysm

OBJECTIVES

Diabetes appears to decrease the risk of subarachnoid hemorrhage. However, it is not clear whether diabetes decreases the risk of aneurysm formation. The aim of our study to evaluate the risk of unruptured cerebral aneurysm in patients with diabetes mellitus.

METHODS

We used data from participants who underwent brain magnetic resonance angiography (MRA) and laboratory tests at the Healthcare System Gangnam Center of Seoul National University Hospital between January 2010 and December 2013. From the 17,368 participants who underwent brain MRA, we analyzed 16,337 subjects whose diabetes status could be identified.

RESULTS

The number of participants with diabetes was 2299 (14.1%). The proportion of participants with cerebral aneurysms was 2.3% in the diabetic group and 2.7% in the non-diabetic group, which was not significantly different (P = 0.225). There were no significant differences in the size, location, and multiplicity of aneurysms between the diabetes and control groups. In multivariate logistic regression, older age showed significant risk effects on cerebral aneurysms, but female sex, hypertension, diabetes, obesity, and smoking did not show significant risk effects.

CONCLUSION

In this study, diabetes did not affect the risk of cerebral aneurysm formation. In addition, neither smoking, nor hypertension was a significant risk factor for unruptured cerebral aneurysms. The lack of association between cerebral aneurysm and the traditional risk factors for subarachnoid hemorrhage requires further study. Risk factors for cerebral aneurysm development and those for cerebral aneurysm rupture may be different.

Intracranial Aneurysms in Patients with Marfan Syndrome: A Multicenter Propensity-Matched Analysis

OBJECTIVE

We sought to identify risk factors for intracranial aneurysms (IAs) in Marfan syndrome (MFS) patients and to describe their characteristics.

METHODS

Patients with confirmed MFS and vessel-dedicated brain imaging from January 1, 1980-December 1, 2020 were categorized according to the presence (IA) or absence (NIA) of IAs. Unmatched logistic regression analysis and propensity score matching were used for comparison.

RESULTS

We included 159 patients, of whom 18 (11.3%) patients had radiographic diagnosis of IAs. Three patients (16.7%) had multiple lesions for a total of 24 IAs. One patient (5.5%) had de novo IA formation. Four patients (22.2%) underwent treatment: Two (11.1%) had open surgical clipping for ruptured aneurysms, and two (11.1%) patients had endovascular embolization for growth. In the unmatched analysis, current tobacco smoker status (odds ratio [OR]: 4.20; confidence interval [CI]: 1.11-15.6; P = 0.027) and history of coronary artery disease (CAD) (OR: 5.79; CI 1.76-20.2; P = 0.004) increased the odds for IA. Propensity score matching yielded 18 IA and 18 NIA patients matched for age, gender, race, prior stroke, and family history of aneurysms. History of CAD (IA = 11 [61.1%] vs. NIA = 4 (22.2%), P = 0.043) and current smoker status (IA = 6 [33.3%] vs. NIA = 0 (0%), P < 0.01) were significantly higher in the IA cohort. Body mass index (P = 0.622), diabetes (P = 0.180), hypertension (P = 0.732), prior stroke (P = 1.00), family history (P = 0.732), alcohol (P = 0.314), recreational drugs (P = 1.00), and other aneurysms (P = 0.585) were not statistically significant.

CONCLUSIONS

Prevalence of IAs in our series of MFS patients was 11.3%, and de novo formation was 5.5%. MFS patients with a history of CAD and current smoker status had an increased risk of IA. Neurovascular radiographic screening should be considered in all patients with MFS, particularly in patients who smoke or have a history of heart disease.

Anterior communicating artery aneurysms: Nonmodifiable morphological parameters associated with rupture risk

BACKGROUND AND PURPOSE

The aim of this study was to investigate the relationship between arterial morphological parameters and the rupture risk of anterior communicating artery (AComA) aneurysms.

METHODS

A hospital database was retrospectively reviewed to identify patients with AComA aneurysms. Morphologic parameters were evaluated on the 3-dimensional computed tomography angiograms. The patients were divided into two groups as ruptured and unruptured. Patient age, sex, morphological parameters such as aneurysm height and weight, neck diameter, aspect ratio (AR), size ratio (SR), bifurcation angle, aneurysm shape, and diameters of the artery were statistically compared between two groups.

RESULTS

Ninety-five AComA aneurysms were analyzed in this study (60 ruptured and 35 unruptured). The aneurysm neck size (p = .005) and the diameter of the A1 segment of the ipsilateral anterior cerebral artery (i-A1) were smaller in the ruptured group than in the unruptured group (p = .001), but AR (p = .001) was higher. The number of patients with irregular shape aneurysm were higher in the ruptured group (p = .006). There was no significant difference between the two groups in terms of age, sex, aneurysm height and weight, bifurcation angle, and SR. Univariate logistic regression analysis showed that i-A1 segment diameter (odds ratio [OR]: -2.070, confidence interval [CI]: 0.030-0.531, p = .005), aneurysm neck diameter (OR: -0.409, CI: 0.491-0.899, p = .008), irregular shape (OR: 1.197, CI: 1.382-7.929, p = .007), and AR (OR: 0.880, CI: 1.315-4.417, p = .004) were significantly correlated with ruptured status. Multivariate regression analysis demonstrated that aneurysm neck diameter (OR: -0.457, CI: 0.410-0.977, p = .039) was the only independent variable for rupture.

CONCLUSION

AComA aneurysm rupture is more likely to occur in aneurysms with smaller i-A1 segment diameter, smaller aneurysm neck diameter, irregular aneurysm shape, and higher AR. Aneurysm neck diameter may be a more important determinant for rupture prediction.

Non-coding RNAs role in intracranial aneurysm: General principles with focus on inflammation

Intracranial aneurysm (IA) is one of the most challenging vascular lesions in the brain for clinicians. It was reported that 1%-6% of the world's population is affected by IAs. Owing to serious complications arising from these lesions, much attention has been paid to better understand their pathophysiology. Non-coding RNAs including short non-coding RNAs and long non-coding RNAs, have critical roles in modulating physiologic and pathological processes. These RNAs are emerging as new fundamental regulators of gene expression, are related with the progression of IA. Non-coding RNAs act via multiple mechanisms and be involved in vascular development, growth and remodeling. Furthermore, these molecules are involved in the regulation of inflammation, a key process in the formation and rupture of IA. Studying non-coding RNAs can yield a hypothetical mechanism for better understanding IA. The present study aims to focus on the role of these non-coding RNAs in the pathogenesis of IA.

Risk Factors for Intraprocedural Rerupture during Embolization of Ruptured Intracranial Aneurysms

BACKGROUND

Intraprocedural rupture (IPR) is a devastating complication in endovascular treatment of ruptured intracranial aneurysms, but its risk factors have not been fully assessed. This study was performed to explore the risk factors for IPR during embolization of ruptured cerebral aneurysms.

METHODS

A total of 1,494 patients with ruptured intracranial aneurysms who underwent endovascular interventional embolization were enrolled. Clinical characteristics were collected for each patient. Univariate and multivariate logistic regression analysis was employed to identify the factors independently associated with IPR. A receiver operating characteristic (ROC) curve analysis was performed to determine the cutoff values of continuous variables predicting IPR.

RESULTS

Forty-one patients suffered from IPR (2.7%). Multivariate logistic regression analysis indicated that aneurysm size (odds ratio [OR], 0.819; 95% confidence interval [CI], 0.732-0.916), aneurysms with irregular morphology (OR, 2.162; 95% CI, 1.143-4.091), time from symptom onset to intervention (OR, 1.615; 95% CI, 1.207-2.161), and vasospasm during embolization (OR, 2.021; 95% CI, 1.038-3.934) were the independent risk factors of IPR. ROC curve analysis showed that the area under the curve for aneurysm size and time from onset to intervention were 0.697 (cutoff value, 3.4 mm; sensitivity, 78.8%; and specificity, 53.7%) and 0.659 (cutoff value, 2 days; sensitivity, 78.0%; and specificity, 45.2%), respectively.

CONCLUSION

Aneurysms with irregular morphology, aneurysms ≤ 3.4 mm in diameter, time from onset to intervention > 2 days and cerebral vasospasm during embolization are independent risk factors for IPR during coil embolization of ruptured aneurysms. More attention should be paid to the factors increasing the risk of IPR in patients with ruptured aneurysms so as to minimize this complication.

Intracranial Hemorrhage From Dural Arteriovenous Fistulas: Symptoms, Early Rebleed, and Acute Management: A Single-Center 8-Year Experience

BACKGROUND

Cerebral dural arteriovenous fistulas (dAVFs) presenting with hemorrhage are so rare that reports on their characteristics and guidelines for their acute management are scarce.

OBJECTIVE

To identify characteristics of the clinical and radiological presentation of hemorrhaging dAVFs, and establish their frequency of early rebleed so that implications for their acute management can be drawn.

METHODS

Retrospective analysis of all patients admitted with intracranial hemorrhage from a dAVF during the years 2011 to 2018.

RESULTS

Twenty patients (14 males) with a median age of 61 yr (27-75 yr) were included. Thunderclap headache was the presenting symptom in 13 (65%) patients. Rebleed prior to treatment occurred in 35% of the patients at median 7.5 h (range 3-96 h) after the ictus. All dAVFs had retrograde venous drainage and a venous aneurysm with a bleb was the source of hemorrhage in 16 (80%) patients, all of them presenting with headache. In contrast, patients bleeding due to diffuse venous hypertension presented with neurological deficits. Endovascular treatment was successful in 2 cases; hence, definite dAVF treatment was surgical in 18 (90%) patients. At median 7 mo (2-29 mo) after the ictus, 13 (65%) patients were in Glasgow Outcome Scale-Extended 7 or 8.

CONCLUSION

The typical presentation of hemorrhage from a cranial dAVF is thunderclap headache. The origin of hemorrhage is often a ruptured venous aneurysm with a bleb. The high frequency of early rebleeds warrants management strategies equivalent to those established for aneurysmal subarachnoid hemorrhage. Overall outcome is favorable.

Intracranial aneurysm management in patients with late-onset Pompe disease (LOPD)

Pompe disease is a rare hereditary metabolic disorder caused by α-glucosidase (GAA) deficiency. The late-onset form of the disease (LOPD) is considered a multisystemic disorder which could involve vascular system with cerebrovascular abnormalities such as intracranial aneurysms or dolichoectasia. Intracranial aneurysm rupture may represent a life-threatening emergency. A possible treatment of unruptured intracranial aneurysms (UIAs) should consider both aneurysm-related (aneurysmal size, shape, localization, numbers and hemodynamic factors) and patient-related risk factors (patient's age and sex, hypertension, smoke exposure). Moreover, UIAs management of LOPD patients needs also to take into account the altered blood vessels integrity and elasticity, whose consistency is likely weakened by the deficient GAA activity as a further potential risk factor. We herein present our approach for of UIAs management in three patients with LOPD. Among them, only one patient with a left saccular UIA of the anterior communicating artery, after careful consideration of risk factors, underwent the endovascular treatment. The other two patients were scheduled for a 1-year follow-up, according to radiological, clinical, and risk evaluation features. Finally, we would like to suggest some general recommendations for UIAs management. In particular, if no risk factors are identified, a cautious yearly follow-up is suggested; otherwise, if risk factors are present, endovascular treatment should be considered.

Size of ruptured intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

There is wide variation in the reported size of ruptured intracranial aneurysms and methods of size estimation. There is widespread belief that small aneurysms < 7 mm do not rupture. Therefore, we performed a systematic review and meta-analysis of the literature to determine the size of ruptured aneurysms according to aneurysm locations and methods of size estimation.

METHODS

We searched PubMed, Cochrane, CINAHL, and EMBASE databases using a combination of Medical Subject Headings (MeSH) terms. We included articles that reported mean aneurysm size in consecutive series of ruptured intracranial. We excluded studies limited to a specific aneurysm location or type. The random-effects model was used to calculate overall mean size and location-specific mean size. We performed meta-regression to explain observed heterogeneity and variation in reported size.

RESULTS

The systematic review included 36 studies and 12,609 ruptured intracranial aneurysms. Overall mean aneurysm size was 7.0 mm (95% confidence interval [CI 6.2-7.4]). Pooled mean size varied with location. Overall mean size of 2145 ruptured anterior circulation aneurysms was 6.0 mm (95% CI 5.6-6.4, residual I² = 86%). Overall mean size of 743 ruptured posterior circulation aneurysms was 6.2 mm (95% CI 5.3-7.0, residual I² = 93%). Meta-regression identified aneurysm location and definition of size (i.e., maximum dimension vs. aneurysm height) as significant determinants of aneurysm size reported in the studies.

CONCLUSIONS

The mean size of ruptured aneurysms in most studies was approximately 7 mm. The general wisdom that aneurysms of this size do not rupture is incorrect. Location and size definition were significant determinants of aneurysm size.

Rupture Risk of Small Unruptured Intracranial Aneurysms in Japanese Adults

Background and Purpose—

Therapeutic decision making for small unruptured intracranial aneurysms (<10 mm) is difficult. We aimed to develop a rupture risk model for small intracranial aneurysms in Japanese adults, including clinical, morphological, and hemodynamic parameters.

Methods—

We analyzed 338 small unruptured aneurysms; 35 ruptured during the observation period, and 303 remained stable. Clinical, morphological, and hemodynamic parameters were considered. Computational fluid dynamics was used to calculate hemodynamic parameters based on computed tomography images of all aneurysms in their unruptured state. Differences between the ruptured and unruptured groups were tested by the Mann-Whitney U or Fisher exact tests. Multivariate logistic regression was applied to obtain a rupture risk model. Its predictive ability was investigated by receiver operating characteristic analysis.

Results—

The risk model revealed that rupture may be more likely to in younger patients (odds ratio [OR], 0.92 for each age increase of 1 year [95% CI, 0.88−0.96] P <0.001) with multiple aneurysms (OR, 2.58 [95% CI, 1.07−6.19] P =0.03), located at a bifurcation (OR, 5.45 [95% CI, 1.87−15.85] P =0.002), with a bleb (OR, 4.09 [95% CI, 1.42−11.79] P =0.009), larger length (OR, 1.91 for each increase of 1 mm [95% CI, 1.42−2.57] P <0.001), and lower pressure loss coefficient (OR, 0.33 for each decrease of 1 unit [95% CI, 0.14−0.77] P =0.01). The sensitivity, specificity, and area under the curve were 0.800, 0.752, and 0.826 (95% CI, 0.739−0.914) respectively.

Conclusions—

Younger age, presence of multiple aneurysms, location at a bifurcation, presence of a bleb, larger length, and lower pressure loss coefficient were identified as risk factors for rupture of small intracranial aneurysms. The risk model should be validated in further studies.

A functional polymorphism in the promoter region of miR-155 predicts the risk of intracranial hemorrhage caused by rupture intracranial aneurysm

BACKGROUND

This study aimed to study the effect and underlying molecular mechanisms of single-nucleotide polymorphism (SNP) rs767649 during the pathogenesis of intracranial aneurysm (IA) rupture.

METHOD

Real-time PCR and Western blot analysis were performed to detect the differentiated expression of miR-155 and matrix metalloproteinase-2 (MMP-2) among different sample groups. Computational analysis and luciferase assay were conducted to study the effect of SNP rs767649 on the expression of miR-155 as well as the regulatory relationship between miR-155 and MMP-2.

RESULTS

In unruptured IA samples, the expression of miR-155 was upregulated while the expression of MMP-2 was downregulated compared with the ruptured IA samples. Similarly, the expression of miR-155 was upregulated while the expression of MMP-2 was downregulated in samples genotyped as AA/AT compared with samples genotyped as TT. In addition, compared with the negative controls, the luciferase activities of cells treated with rs767649A and rs767649T were both elevated with rs767649A-transfected cells expressing the highest luciferase activity. Furthermore, a negative relationship was established between miR-155 and MMP-2 by measuring the luciferase activity of cells cotransfected with miR-155 and the wild-type 3'-untranslated region of MMP-2.

CONCLUSION

The results of this study showed that the SNP rs767649 in the promoter of miR-155 could reduce the transcription activity of miR-155, while poorly expressed miR-155 could increase the incidence of IA rupture by increasing the expression of MMP-2, especially in subjects carrying the TT genotype of SNP rs767649.

Comparison of Supraorbital and Pterional Keyhole Approach for Clipping Middle Cerebral Artery Aneurysm: A Chinese Population-Based Study

OBJECTIVE

Keyhole craniotomy is a minimally invasive approach for the treatment of middle cerebral artery (MCA) aneurysms. The aim of this study was to compare the clinical outcome between supraorbital keyhole approach and pterional keyhole approach (PKA) in Chinese patients with MCA aneurysm.

METHODS

Consecutive patients with MCA aneurysms were reviewed between January 2013 and December 2017. Efficacy and safety between PKA and supraorbital keyhole approach were compared. Poor outcome was defined as modified Rankin Scale score of 3-6 at discharge.

RESULTS

This study enrolled 260 patients; 222 (85.4%) had ruptured aneurysm, and 183 (70.4%) received PKA. The distribution of PKA in unruptured and ruptured aneurysms showed no significant difference (P > 0.05). In subgroup analyses, PKA was more likely associated with poor outcome at discharge in patients with unruptured aneurysms (odds ratio = 5.500, 95% confidence interval = 1.013-29.850, P = 0.048), whereas approach selection was not an independent factor predicting poor outcome in patients with ruptured aneurysms (P > 0.05).

CONCLUSIONS

In a Chinese population, supraorbital keyhole approach was superior to PKA in improving outcome in patients with unruptured MCA aneurysms, but the 2 approaches showed comparable outcomes at discharge in patients with ruptured aneurysms.