Small Intracranial Aneurysms Research Articles

The value of systemic immune inflammation index, white blood cell to platelet ratio, and homocysteine in predicting the instability of small saccular intracranial aneurysms

Inflammation has a destructive effect on the homeostasis of the vascular wall, which is involved in the formation, growth, and rupture of human intracranial aneurysms (IAs) disease progression. However, inflammation-related markers have not been well studied in the risk stratification of unruptured IAs. The purpose of this study was to investigate the predictive value of serum inflammatory markers in the unstable progression of small saccular intracranial aneurysms (SIAs). This study retrospectively included 275 patients with small SIAs (aneurysm diameter less than or equal to 7 mm), to compare the level difference of serum inflammatory complex marker systemic immune-inflammatory index (SII), white blood cell to platelet ratio (WPR), and homocysteine (Hcy) in patients with stable (asymptomatic unruptured) and unstable (symptomatic unruptured, ruptured) small SIAs. 187 patients (68%) had aneurysm-related compression symptoms and rupture outcomes. In the multivariate logistic regression after adjusting for baseline differences, SII, WPR, and Hcy were independent risk factors for the instability of small SIAs, the prediction model combined with other risk factors (previous stroke history, aneurysm irregularity) showed good predictive ability for the instability of small SIAs, with an area under the curve of 0.905. In addition, correlation analysis showed that SII, WPR, and Hcy also had significant differences in patients with symptomatic unruptured and ruptured small SIAs, and higher inflammation levels often promoted the disease progression of small SIAs. Higher levels of SII, WPR and Hcy can be used as independent predictors of instability of small SIAs. As an economical and convenient biomarker, it is crucial for clinical treatment strategies of stable small SIAs.

Does it stable? Intracranial aneurysm wall enhancement might be the warning signals: a meta-analysis of observational studies.

Magnetic resonance vessel wall imaging (MR-VWI) is an emerging imaging technology used to assess the progressive risk of unruptured intracranial aneurysms (UIAs). Unlike the standard evaluation model, MR-VWI is still debatable. This study aims to further define the potential relationship between aneurysm wall enhancement (AWE) and aneurysm stability. Using "intracranial aneurysm", "magnetic resonance", and "enhancement" as keywords, relevant studies were systematically searched in PubMed, Embase, and Cochrane, and the qualified studies were enrolled for further analysis. There were 13 case-control studies, 4 cohort studies, and 2,678 cases of intracranial aneurysms included in the meta-analysis. It was shown that AWE was correlated with intracranial aneurysm rupture (OR = 35.90, 95% CI: 15.58 to 82.75, p < 0.001), growth (OR = 6.69, 95% CI: 2.69 to 16.63, p < 0.001), and presence of symptoms (OR = 14.46, 95% CI: 9.07 to 23.05, p < 0.001). This finding had a high diagnostic value, but the correlation was probably not independent of aneurysm size. The pooled relative risks of the follow-up studies revealed that the risk of UIA progression was approximately 3.33 times higher with AWE than without AWE (RR = 3.33, 95% CI: 2.33 to 4.78, p < 0.001). In addition, the pooled results demonstrated that quantitative indices of VWI enhancement were equally linked with aneurysm stability (OR = 19.61, 95% CI: 10.63 to 36.17, p < 0.001). AWE is an effective imaging method to assess the stability of UIAs, and it can be a marker for the prophylactic treatment of small unruptured intracranial aneurysms in the future, which remains to be validated by prospective studies with large samples.

Endovascular Embolization of Intracranial Aneurysms Using Target Tetra Detachable Coils: Angiographic and Clinical Results from a Single Center.

Background/Objectives: Target tetra detachable coils (TTDCs) aid in achieving effective framing during the coil embolization of small intracranial aneurysms by maintaining a tetrahedral conformation within the aneurysm sac. We aimed to report the initial experience of patients treated for intracranial aneurysms using TTDCs, with a specific focus on efficacy and safety. Methods: We retrospectively reviewed the medical records of 41 patients who underwent the coil embolization of intracranial aneurysms sized ≤10 mm with TTDCs between April and May 2023. Post-procedural angiographic and clinical results were reviewed. Results: Of the 46 aneurysms (45 unruptured and 1 ruptured), 33 (71.7%) were treated with the stent-assisted technique and 13 (28.3%) using the simple coil embolization technique. Post-procedural angiography showed complete occlusion in 41 aneurysms (89.1%), neck remnants in 1 (2.2%), and residual aneurysms in 4 (8.7%). The mean packing density was 34.7% (19.3-46.8%), with TTDC coil length comprising a mean of 88.5% of the total coil length. No major device- or procedure-related complications were observed. During the follow-up, 40 aneurysms (93.0%) demonstrated complete occlusion, while neck remnants were observed in 1 (2.3%), and residual aneurysms in 2 (4.7%). No cases of recanalization were observed. Conclusions: The TTDC is a safe and effective device for the endovascular treatment of intracranial aneurysms. Follow-up studies are required to establish long-term results.

Clinical relevance of critical plasma homocysteine levels in predicting rupture risk for small and medium-sized intracranial aneurysms

Plasma homocysteine (Hcy) has been globally recognized as an independent risk factor for various neurovascular diseases. In this study, the authors investigated the relationship between critical Hcy concentration and the risk of rupture in intracranial aneurysms (IAs). This study collected data from 423 patients with both ruptured and unruptured IAs. We compared demographic data, vascular rupture risk factors, and laboratory test results between the two groups. Multivariable logistic regression analysis was employed to determine the correlation between critical plasma Hcy levels and the risk of rupture in small to medium-sized IAs. A total of 330 cases of ruptured intracranial aneurysms (RIA) and 93 cases of unruptured intracranial aneurysms (UIA) were included. Univariate analysis revealed statistically significant differences between the ruptured and unruptured groups in terms of hypertension, hyperlipidemia, plasma Hcy levels, and IA morphology (all P < 0.05). Multivariable logistic regression analysis indicated that hypertension (odds ratio [OR] 0.504; 95% confidence interval [CI] 0.279–0.911; P = 0.023), hyperlipidemia (OR 1.924; 95% CI 1.079–3.429; P = 0.027), and plasma Hcy levels (OR 1.420; 95% CI 1.277–1.578; P < 0.001) were independently associated with the rupture of small to medium-sized IAs, all with statistical significance (P < 0.05). Our study suggests that critical plasma Hcy levels are an independent risk factor for increased rupture risk in small to medium-sized intracranial aneurysms. Therefore, reducing plasma Hcy levels may be considered a valuable strategy to mitigate the risk of intracranial vascular abnormalities rupture and improve patient prognosis.

Development and Validation of a Risk Predictive Model for Small Intracranial Aneurysms in Adults Over a Five-Year Period.

Objective The optimal management of a small intracranial aneurysm (sIA) remains a challenge due to the lack of a size-specific risk predictive model for aneurysm rupture. We aimed to develop and validate a nomogram-based risk predictive model for sIA. Methods A total of 382 patients harboring 215 ruptured and 167 unruptured small intracranial aneurysms (uSIAs) (≤ 7 mm) were recruited and divided into training and validation cohorts. Risk factors for the construction of a nomogram were selected from clinical and aneurysmal features by least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression. The nomogram for risk of rupture was evaluated in both the training and validation cohorts for discrimination, calibration, and clinical usefulness. Results Hyperlipidemia (odds ratio (OR)=2.74, 95% confidence interval (CI)=1.322~5.956, P=0.008), the presence of a daughter dome (OR=3.068, 95%CI=1.311~7.598, P=0.012), larger size-to-neck ratio (SN) (OR=1.807, 95%CI=1.131~3.063, P=0.021) and size ratio (SR) (OR=2.221, 95%CI=1.262~4.025, P=0.007) were selected as independent risk factors for sIA rupture and used for construction of nomogram. Internal validation by bootstrap sampling showed the Concordance index (C index) of 0.756 for the nomogram. The calibration by the Hosmer-Lemeshow test showed a P value of 0.847, indicating the model was well-fitted. Additionally, decision curve analysis (DCA) demonstrated that the predictive model has good clinical usefulness, providing net benefits across a range of threshold probabilities, thus supporting its application in clinical decision-making. Conclusion The risk prediction model can reliably predict the risk of sIA rupture, which may provide an important reference for optimizing the therapeutic strategy.

Prevalence of Risk Factors in Patients with Postprocedural Ischemic Lesions after Coiling of Very Small Intracranial Aneurysms.

Background: Very small intracranial aneurysms, generally considered to be those 3 mm in diameter or smaller, pose particular technical challenges for endovascular surgeons. For this reason, very small aneurysms have been excluded from many relevant studies. The aim of our research was to establish the risk factors for the occurrence of stroke complications after endovascular embolization of ruptured and unruptured small intracranial aneurysms. Methods: During the period of 2009-2023, our team performed endovascular embolizations of intracranial aneurysms in 1567 patients across four different centers within the territory of Serbia and Montenegro. Within the total number of patients mentioned, aneurysms of less than 4 mm were treated 185 times, with 119 ruptured and 66 unruptured. Results: In the group of 119 patients with ruptured small intracranial aneurysms, 19 (16%) patients had ischemia after the endovascular treatment, 6 (5%) patients had minor neurological deficits, while 13 (10.9%) patients had major neurological deficits, of which 6 (5%) patients died. In the group of 66 patients with unruptured small intracranial aneurysms, 7 (10.6%) patients had ischemia after the endovascular treatment, 5 (7.6%) patients had minor neurological deficits, and 2 (3.03%) had major neurological deficits. Multivariate binary logistic regression showed that the risk factors for the occurrence of ischemia were the patient's age, smoking and alcohol consumption. The type of endovascular treatment used also had a statistically significant effect on the development of ischemia. Conclusions: Understanding the influence of possible risk factors for the occurrence of ischemic insult after embolization of small intracranial aneurysms is of great importance. By recognizing them, periprocedural complications can be reduced to a minimum.

A multicenter study of the efficacy and safety of treatments (endovascular or conservative) in small intracranial aneurysms in Colombia.

The registry of cerebral aneurysms <5 mm, known for their low risk of rupture, is significant, given their high incidence globally. Our study aimed to identify, in small aneurysms (<5 mm), the potential morphological characteristics, risk factors that can predict the risk of rupture, and the risk or benefit of treating them with endovascular or conservative treatment in ruptured and unruptured intracranial aneurysms. The medical records of patients with cerebral aneurysms <5 mm were retrospectively reviewed between January 2014 and December 2022 at two neurovascular centers in Colombia. We evaluated clinical and angiographic outcomes using statistical tests. Two hundred fifty-six patients (425 intracranial aneurysms) were registered in the database. Two hundred and seventy-five IA were treated with endovascular treatment: 70 ruptured aneurysms and 205 unruptured aneurysms. One hundred fifty intracranial aneurysms underwent conservative treatment (follow-up). Women accounted for 82.1% of cases. Most cases were incidentally diagnosed (83.5%). After a year of follow-up, 87.3% of unruptured and 67.1% of ruptured intracranial aneurysms had an mRS 0-2. In the Raymond-Roy occlusion classification, among 101 unruptured intracranial aneurysms embolized were 53 cases class I, and among 66 ruptured intracranial aneurysms embolized, 67.1% were class I. Endovascular therapy for aneurysms <5 mm appears to be a technically feasible treatment, with satisfactory occlusion rates and few re-treatments at the 12-month follow-up. The complication rates were similar to those reported in studies on small aneurysms.

Mid-term safety and efficacy in small intracranial aneurysm coiling: results from TARGET® nano prospective independent core lab adjudicated multicenter registry.

The primary objective is to evaluate the safety and effectiveness of Stryker second generation Target® Nano Coils in the treatment of ruptured and unruptured small (<7 mm) intracranial aneurysms. The TARGET Registry is a prospective, two-arm study with independent medical event monitoring and core-lab adjudication. This paper describes the second arm of the TARGET registry. Patients with de novo intracranial aneurysms were embolized with 2nd generation TARGET Nano coils in 12 US centers. The primary efficacy outcome was adequate aneurysm occlusion (RR occlusion grade I-II) on follow-up. Primary safety outcome was treatment-related morbidity and mortality. Secondary outcomes included aneurysm packing density immediately post-procedure, immediate adequate occlusion, aneurysm re-access rate, retreatment rate and clinical outcomes using modified ranking scale. A secondary analysis investigated the influence of using Nano-predominant coils (≥2/3 of total coil-length) vs. non-Nano-predominant coils (<2/3 of total length). 150 patients with 155 aneurysms met the inclusion and exclusion criteria. (31%) patients with ruptured and (69%) with unruptured aneurysms were treated using TARGET coils. Median age was 58.8 (SD 12.7), 74.7% were females, and 80% were Caucasians. Mean follow-up was 5.23 (SD 2.27) months. Peri-procedural mortality was seen in 2.0% of patients. Good outcome at discharge (mRS 0-2) was seen in 81.3% of the cohort. The median packing density (SD) was 29.4% (14.9). Mid-term complete/near complete occlusion rate was seen in 96% of aneurysms and complete obliteration was seen in 75.2% of aneurysms. Patients treated predominantly with Nano coils had higher PD (32.6% vs. 26.1%, p < 0.001). There was no significant difference in clinical and angiographic outcomes. The mid-term mRS0-2 was achieved in 106/109 (97.2%) patients. All-cause mortality was 5/115 (4.3%). In the multicenter TARGET Registry, 75.8% of aneurysms achieved mid-term complete occlusion, and 96% achieved complete/near complete occlusion with excellent independent functional outcome.

Prediction of small intracranial aneurysm rupture status based on combined Clinical–Radiomics model

BackgroundAccumulating small unruptured intracranial aneurysms are detected due to the improved quality and higher frequency of cranial imaging, but treatment remains controversial. While surgery or endovascular treatment is effective for small aneurysms with a high risk of rupture, such interventions are unnecessary for aneurysms with a low risk of rupture. Consequently, it is imperative to accurately identify small aneurysms with a low risk of rupture. The purpose of this study was to develop a clinically practical model to predict small aneurysm ruptures based on a radiomics signature and clinical risk factors. MethodsA total of 293 patients having an aneurysm with a diameter of less than 5 mm, including 199 patients (67.9 %) with a ruptured aneurysm and 94 patients (32.1 %) without a ruptured aneurysm, were included in this study. Digital subtraction angiography or surgical treatment was required in all cases. Data on the clinical risk factors and the features on computed tomography angiography images associated with the aneurysm rupture status were collected simultaneously. We developed a clinical–radiomics model to predict aneurysm rupture status using multivariate logistic regression analysis. The combined clinical–radiomics model was constructed by nomogram analysis. The diagnostic performance, clinical utility, and model calibration were evaluated by operating characteristic curve analysis, decision curve analysis, and calibration analysis. ResultsA combined clinical–radiomics model (Area Under Curve [AUC], 0.85; 95 % confidence interval [CI], 0.757–0.947) showed effective performance in the operating characteristic curve analysis. In the validation cohort, the performance of the combined model was better than that of the radiomics model (AUC, 0.75; 95 % CI, 0.645–0.865; Delong's test p-value = 0.01) and the clinical model (AUC, 0.74; 95 % CI, 0.625–0.851; Delong's test p-value <0.01) alone. The results of the decision curve, nomogram, and calibration analyses demonstrated the clinical utility and good fitness of the combined model. ConclusionOur study demonstrated the effectiveness of a clinical–radiomics model for predicting rupture status in small aneurysms.

Nomogram-based geometric and hemodynamic parameters for predicting the growth of small untreated intracranial aneurysms.

Previous studies have shown that the growth status of intracranial aneurysms (IAs) predisposes to rupture. This study aimed to construct a nomogram for predicting the growth of small IAs based on geometric and hemodynamic parameters. We retrospectively collected the baseline and follow-up angiographic images (CTA/ MRA) of 96 small untreated saccular IAs, created patient-specific vascular models and performed computational fluid dynamics (CFD) simulations. Geometric and hemodynamic parameters were calculated. A stepwise Cox proportional hazards regression analysis was employed to construct a nomogram. IAs were stratified into low-, intermediate-, and high-risk groups based on the total points from the nomogram. Receiver operating characteristic (ROC) analysis, calibration curves, decision curve analysis (DCA) and Kaplan-Meier curves were evaluated for internal validation. In total, 30 untreated saccular IAs were grown (31.3%; 95%CI 21.8%-40.7%). The PHASES, ELAPSS, and UIATS performed poorly in distinguishing growth status. Hypertension (hazard ratio [HR] 4.26, 95%CI 1.61-11.28; P = 0.004), nonsphericity index (95%CI 4.10-25.26; P = 0.003), max relative residence time (HR 1.01, 95%CI 1.00-1.01; P = 0.032) were independently related to the growth status. A nomogram was constructed with the above predictors and achieved a satisfactory prediction in the validation cohort. The log-rank test showed significant discrimination among the Kaplan-Meier curves of different risk groups in the training and validation cohorts. A nomogram consisting of geometric and hemodynamic parameters presented an accurate prediction for the growth status of small IAs and achieved risk stratification. It showed higher predictive efficacy than the assessment tools.

Use of the Tubridge flow diverter in the treatment of intracranial aneurysms: a single center experience

To investigate the safety and effect of Tubridge flow diverter deployment for the treatment of intracranial aneurysms, 85 patients with intracranial aneurysms treated with the Tubridge flow diverter were retrospectively enrolled. The clinical data including the baseline data, aneurysm parameters before and after treatment, and follow-up outcomes were assessed. Among 85 patients, there were 35 (41.2%) males and 50 females (58.8%) aged 17–77 (mean 56.7 ± 11.1) years with 110 aneurysms. Five (5.9%) patients initially presented with subarachnoid hemorrhage from aneurysm rupture. The aneurysm size was 2–30 (mean 8.6) mm, and the aneurysm neck was 2–10.6 (mean 5.7 ± 2.3) mm. Ninety-three Tubridge stents were deployed. Twenty-five (29.4%) patients experienced adjunctive loose coiling. Blood flow was significantly reduced from entering the aneurysm after stent deployment. Periprocedural complications occurred in three (3.5%) patients, including in-stent thrombosis during embolization in one patient (1.2%), conjunctiva edema on the right in one patient (1.2%), and acute multiple cerebral infarctions in one patient (1.2%). Angiographic follow-up was conducted in 67 (78.8%) patients 3–36 (mean 15.3 ± 5.6) months later. In 11 (16.4% or 11/67) patients, blood flow still entered the aneurysm with the O’Kelly-Marotta (OKM) grade B in two (3.0%) patients and grade C in nine (13.4%), whereas complete occlusion (OKM grade D) was achieved in the other 56 (83.6% or 56/67) aneurysms. In-stent stenosis was present in five (7.5%) patients with approximately 25% stenosis in three (4.5%) patients and 50% in two (3.0%). In conclusion, the Tubridge flow diverter can be safely and efficiently applied in the treatment of small and large intracranial aneurysms, with a low periprocedural complication rate, a high occlusion degree, and a low in-stent stenosis rate at follow-up even though large aneurysms may necessitate a longer surgical time and adjunctive coiling.

Abstract WP181: Treatment of Unruptured Small and Medium Wide-Necked Aneurysms of the Internal Carotid Artery Using the 64-Wire Surpass Evolve: Results of the SEASE International Registry

Introduction: The management of wide-necked internal carotid artery (ICA) aneurysms is technically challenging with established endovascular and microsurgical techniques that are limited by the associated morbidity and/or recurrence. The PREMIER study first demonstrated high rates of complete occlusion without parent vessel stenosis or permanent neurological complications after the treatment of wide-necked small and medium-sized intracranial ICA aneurysms with the 48-wire pipeline. We aimed to assess the effectiveness and safety of the new generation 64-wire Surpass Evolve (SE) flow diverter for the treatment of the same intracranial ICA aneurysm population. Methods: This is a sub-analysis from the Safety and Effectiveness Assessment of the Surpass Evolve (SEASE) registry, an observational cohort study including 15 academic institutions in North America and Europe spanning between 2020-2023. Analysis included patients with unruptured wide-necked saccular aneurysms (not previously treated), measuring &lt;12 mm along the ICA segments. Primary effectiveness was complete occlusion (Raymond Roy Class 1) without retreatment at 1-year follow-up (core lab adjudicated), and primary safety was major stroke (ischemic/hemorrhagic) in the territory supplied by the target artery or death. Results: 129 cases were included (median age 58 years, IQR: 50-67 years, 85% females). Median aneurysm and neck size were 5.8 mm (IQR: 4.0-7.5) and 4.1 (IQR, 3.0-5.5). Most aneurysms were in the ICA C6 segment (66.7%, 86/129), followed by the C7 segment (21.0%, 21/129). Successful implantation was encountered in 99% (128/129) of the cases. At a median 10.1 months (IQR: 6.3-12.6), the rate of complete occlusion was 75.2% (91/121), ≥50% in-stent stenosis 7% (9/129), and retreatment 0.8% (1/129). Major stroke and overall mortality were reported in 1.6% (2/129) of the cases. Conclusion: Our study evaluating outcomes from the SEASE international multicenter registry found that patients with wide-necked unruptured saccular small to medium-sized aneurysms can be effectively treated with the 64-wire chrome-cobalt SE. Furthermore, the SE showed a considerable safety profile for this patient population.

Evaluation of PHASES Score for Predicting Rupture of Intracranial Aneurysms: Significance of Aneurysm Size

IntroductionRecent data has identified that certain risk factors for rupture differ between small and larger intracranial aneurysms (IAs). Such differing risk factors make up 5 out of the 6 predictor variables used in the PHASES score which raises the question on whether IA size has a significant effect on the score’s performance. MethodsPatients which were diagnosed with an IA incidentally or due to a subarachnoid hemorrhage (SAH) between 2015-2023 were selected for potential inclusion. The median IA size of the cohort was chosen as the cutoff point to categorize small and large (6 mm). The PHASES score was calculated for all patients and a receiver operating characteristic curve analysis was performed to evaluate the classification accuracy of PHASES in predicting rupture for small and large IAs. ResultsA total of 677 IAs were included. Among the IAs, 400 (58.9%) presented as UIAs and 279 (41.0%) as SAH. The average PHASES score was 2.9 and 6.5 for small (n = 322) and large (n = 355) IAs, respectively. The PHASES score performed significantly lower for predicting rupture in smaller IAs (area under the curve [AUC]: 0.634) compared to the larger (AUC: 0.741) (p = 0.00083). ConclusionPHASES was shown to underperform on small IAs. The decision to treat small unruptured IAs remains highly controversial and the development of a new score to estimate the annual rupture rate while accounting for IA morphology is of great need. Our findings can help encourage future researchers to develop such a score.

Multiple Small, Medium and Large Intracranial Aneurysms in a Single Patient

Multiple Small, Medium and Large Intracranial Aneurysms in a Single Patient

Correlation of Flow Diverter Malapposition at the Aneurysm Neck with Incomplete Aneurysm Occlusion in Patients with Small Intracranial Aneurysms: A Single-Center Experience.

Flow diversion treatment repairs aneurysms by altering the hemodynamics of the aneurysmal sac and providing a scaffold for endothelial cell adhesion. The purpose of this study was to investigate the correlation of flow diverter (FD) malapposition at the aneurysm neck with incomplete occlusion of small intracranial aneurysms (IAs) and investigate other factors that are possibly related to incomplete occlusion. From January 2019 to June 2022, the clinical and imaging data for 153 patients (175 aneurysms) with unruptured small IAs treated with flow diversion were retrospectively analyzed. FD apposition at the aneurysm neck was evaluated by high-resolution conebeam CT (HR-CBCT), and the complete occlusion rate for aneurysms was judged according to the latest follow-up conventional angiography findings (≥6 months). Multivariate logistic regression analysis was used to determine factors associated with incomplete aneurysm occlusion. In total, 159 FDs were implanted in 153 patients. HR-CBCT performed after the deployment revealed FD malapposition at the aneurysm neck in 18 cases. According to the latest follow-up angiograms (average: 9.47 ± 3.35 months), the complete aneurysm occlusion rate was 66.9%. The complete occlusion rates for incomplete and complete stent apposition at the neck were 38.9% (7/18) and 70.1% (110/157), respectively. The results of regression analysis showed that an aneurysm sac with branch vessels (OR, 2.937; P = .018), incomplete stent apposition at the aneurysm neck (OR, 3.561; P = .023), and a large aneurysm diameter (OR, 1.533; P = .028) were positive predictors of incomplete aneurysm occlusion. An aneurysm sac with branch vessels, a large aneurysm diameter, and malapposition at the aneurysm neck significantly affect aneurysm repair after FD stent-only treatment for small IAs.

Glypican-1 may be a plasma biomarker for predicting the rupture of small intracranial aneurysms.

Currently, there are no effective methods for predicting the rupture of asymptomatic small intracranial aneurysms (IA) (<7 mm). In this study the aim was to identify early warning biomarkers in peripheral plasma for predicting IA rupture. Four experimental groups were included: ruptured intracranial aneurysm (RIA), unruptured intracranial aneurysm (UIA), traumatic subarachnoid hemorrhage control (tSAHC), and healthy control (HC) groups. Plasma proteomics of these four groups were detected using iTRAQ combined LC-MS/MS. Differentially expressed proteins (DEPs) were identified in RIA, UIA, tSAHC compared with HC. Target proteins associated with aneurysm rupture were obtained by comparing the DEPs of the RIA and UIA groups after filtering out the DEPs of the tSAHC group. The plasma concentrations of target proteins were validated using enzyme-linked immunosorbent assay (ELISA). The iTRAQ analysis showed a significant increase in plasma GPC1 concentration in the RIA group compared to the UIA group, which was further validated among the IA patients. Logistic regression analysis identified GPC1 as an independent risk factor for predicting aneurysm rupture. The ROC curve indicated that the GPC1 plasma cut-off value for predicting aneurysms rupture was 4.99 ng/ml. GPC1 may be an early warning biomarker for predicting the rupture of small intracranial aneurysms. SignificanceThe current management approach for asymptomatic small intracranial aneurysms (<7 mm) is limited to conservative observation and surgical intervention. However, the decision-making process regarding these options poses a dilemma due to weighing their respective advantages and disadvantages. Currently, there is a lack of effective diagnostic methods to predict the rupture of small aneurysms. Therefore, our aim is to identify early warning biomarkers in peripheral plasma that can serve as quantitative detection markers for predicting intracranial aneurysm rupture. In this study, four experimental populations were established: small ruptured intracranial aneurysm (sRIA) group, small unruptured intracranial aneurysm (sUIA) group, traumatic subarachnoid hemorrhage control (tSAHC) group, and healthy control (HC) group. The tSAH group was the control group of spontaneous subarachnoid hemorrhage caused by ruptured aneurysm. Compared with patients with UIA, aneurysm tissue and plasma GPC1 in patients with RIA is significantly higher, and GPC1 may be an early warning biomarker for predicting the rupture of intracranial small aneurysms.

Modeling and evaluation of biomechanics and hemodynamic based on patient-specific small intracranial aneurysm using fluid-structure interaction

Background and ObjectiveRupture of small intracranial aneurysm (IA) often leads to the development of highly fatal clinical syndromes such as subarachnoid hemorrhage. Due to the patient specificity of small IA, there are many difficulties in evaluating the rupture risk of small IA such as multiple influencing factors, high clinical experience requirements and poor reusability. MethodsIn this study, clinical methods such as transcranial doppler (TCD) and magnetic resonance imaging (MRI) are used to obtain patient-specific parameters, and the fluid-structure interaction method (FSI) is used to model and evaluate the biomechanics and hemodynamics of patient-specific small IA. ResultsThe results show that a spiral vortex stably exists in the patient-specific small IA. Due to the small size of the patient-specific small IA, the blood flow velocity still maintains a high value with maximum reaching 3 m/s. The inertial impact of blood flow and vortex convection have certain influence on hemodynamic and biomechanics parameters. They cause three high value areas of WSSM on the patient-specific small IA with maximum of 180 Pa, 130 Pa and 110 Pa, respectively. They also cause two types of WSS concentration points, positive normal stress peak value areas and negative normal stress peak value areas to appear. ConclusionThis paper found that the factors affecting hemodynamic parameters and biomechanical parameters are different. Unlike hemodynamic parameters, biomechanical parameters are also affected by blood pressure in addition to blood flow velocity. This study reveals the relationship between the flow field distribution and changes of patient-specific small IA, biomechanics and hemodynamics.

Safety and efficacy of braided stents as stent monotherapy for the treatment of small intracranial aneurysms.

The safety and efficacy of low-profile braided stent as stent monotherapy require further investigation. To analyze patient outcomes after treatment with braided stents used as "light" flow diverters. Retrospective study to evaluate the occlusion rate of aneurysms treated with braided stent and remodeling of covered side branches and perforators. Several factors potentially influencing aneurysm occlusion were analyzed. Thirty-five aneurysms in 31 patients were included. Six aneurysms (17.1%) had an acute subarachnoid hemorrhage. Braided stent was used as retreatment among 9 previously coiled aneurysms (25.7%). A total occlusion was achieved in 18 aneurysms (51.4%), entry remnant in 3 aneurysms (8.6%), incomplete filling in 6 aneurysms (17.1%) and complete filling in 8 aneurysms (22.9%). None of the aneurysms ruptured during the follow-up period. Of 32 stents deployed, we observed 3 cases (9.4%) of asymptomatic mild stenosis and 3 cases (10.7%) of narrowing of covered branches among 28 covered arteries. There were no cases of perforator infarction and no mortality or permanent morbidity associated with the treatment. Moreover, aneurysms <2.5 mm, aneurysms with a neck <1.8 mm, those with a mean aspect-ratio of 1.4, and lateral wall aneurysms had a higher frequency of adequate occlusion. Braided stents used as stent monotherapy appear to be sufficiently effective in the treatment of very small intracranial aneurysms, despite a lower overall occlusion rate compared to a standard flow diversion strategy. However, given the low morbidity rate, this strategy may be an alternative to flow-diverter stents for small and distally located lesions.

Risk factors for perianeurysmal vasogenic oedema (pavo) following embolization therapy: literature review.

Perianeurysmal vasogenic oedema (PAVO) is a rare complication associated post-embolisation of intracranial aneurysms. The prevalence, risk factors predisposing to susceptibility, and pathologic mechanisms underlying this process are not clearly understood. Since this complication may be associated with poor clinical outcomes, the authors designed this study to describe possible risk factors, underlying mechanisms, and management of PAVO through published case reports.Developing a priori protocol according to PRISMA guidelines, we searched MEDLINE/PubMed, Embase and Web of Science to identify case studies and reports of adult patients with intracranial aneurysms who developed perianeurysmal oedema following coil embolization therapy. Data extracted from these studies included patient demographics, aneurysm characteristics, coil type, PAVO characteristics, treatment, and outcomes. Quality was assessed using a standardized tool.21 eligible studies of acceptable quality were identified, comprising 40 unique cases from 9 countries. The mean patient age was 56.4years and 25 (62.5%) were female. Aneurysm size ranged from 6 to 30mm, with a mean size of 15.2mm; only 6 (15%) of cases were giant intracranial aneurysm (≥ 25mm). The more frequent locations of intracranial aneurysms associated with PAVO were the ICA (50%) and posterior circulation (32.5%), with 7.5% and 10% of cases occurring in MCA and anterior circulation, respectively. 16 cases (40%) were treated with bare platinum coils, and 14 (35%) with a combination of BPCs and bioactive coils; in 10 cases (25%), the coil type was not mentioned. PAVO presented between 0days and 8years of coil embolization, with 23 (57.5% cases) presenting symptomatically in relation to brain region affected. Management strategies for PAVO included conservative, steroids, re-embolization, clipping, stenting, parent artery occlusion either as monotherapy or as combination therapy. Of reported studies, 26 treated cases (65%) resolved, with 8 (20%) remaining stable, and 4 (10%) deteriorating.PAVO can be associated with small or large intracranial aneurysms, bare and bioactive platinum coils, and all regions of the intracranial circulation. The understanding of the risk factors of this complication lies in the underlying mechanisms, which will ultimately guide appropriate patient follow-up and subsequent optimal management.

Coil embolization for ruptured and unruptured very small intracranial aneurysms: A retrospective review of a 10-year single-center experience.

Because of the risk of intraoperative rupture and technical difficulties, coil embolization of very small aneurysms (VSIAs) with a diameter of ≤3 mm is challenging. Herein, we reviewed our treatment strategies and outcomes in performing coil embolization for VSIAs compared to those for larger sized intracranial aneurysms (IAs) with 4 to 4.5 mm. We retrospectively reviewed the data on ruptured and unruptured VSIAs and larger-sized IAs treated with coiling from January 2012 to June 2021. Saccular IAs treated with coil embolization and followed up for at least 6 months with imaging studies were included in the study. Fifty-eight VSIAs (27 subarachnoid hemorrhages [SAH group] and 31 unruptured hemorrhages [URA group]) were identified. The wide-necked VSIAs were significantly more common in the URA group (90.3% vs 63.0%, P = .013). Procedural complications occurred in 8 cases (13.8%): intra-procedural rupture (n = 3), coil prolapse (n = 3), and thromboembolic events (n = 2). Complications were more frequent in the SAH group (P = .020). SAH was an independent risk factor for procedural complications (odds ratio, 11.293 [95% confidence interval: 1.173-108.684], P = .036), and the outcomes were affected by SAH presentation (P = .007) and poor clinical status of SAH (P = .001). When compared with larger IAs (n = 57), there were no significant differences in treatment outcomes, procedural complications, and clinical outcomes. VSIAs ≤ 3 mm in diameter were successfully treated with coil embolization, with reasonable procedure-related complications and treatment outcomes. The safety and efficacy of coil embolization for VSIAs were comparable to those of 4 to 4.5 mm sized IAs in this single-center cohort.