Small Aneurysms Research Articles

Rupture Risk Factors and Strategies for Unruptured Distal Anterior Cerebral Artery Aneurysms

Distal anterior cerebral artery (dACA) aneurysms are rare. Ruptured dACA aneurysms typically present with subarachnoid hemorrhage in conjunction with intracerebral hematoma and cause neurological deterioration. This study aimed to determine their risk of rupture and examine associated factors. We retrospectively analyzed patients with dACA aneurysms to compare patient and aneurysm characteristics between ruptured and unruptured aneurysms. Clinical outcome was used the modified Rankin scale. Univariate analyses were performed to identify rupture risk factors. One hundred three patients with dACA aneurysms were examined (51 ruptured and 52 unruptured). The median aspect ratio of ruptured and unruptured aneurysms was 1.69 and 1.22, respectively (P<0.01). The median maximum diameter of ruptured and unruptured aneurysms was 5.2 and 3.1mm, respectively (P<0.01). The median size ratio of ruptured and unruptured aneurysms was 3.32 and 2.17, respectively (P<0.01). Maximum diameter was <5mm in 45.2% of ruptured dACA aneurysms. dACA aneurysm, showing size ratio >2.4 and aspect ratio >1.4, had ruptured in 71.4% and 78.6%, respectively. We suggested that these are the threshold of size ratio and aspect ratio for rupture of dACA aneurysms. A total percentatge of 78.1% of aneurysms with aspect ratio >1.4 and size ratio >2.4 had ruptured. Distal anterior cerebral artery (dACA) aneurysms may rupture, even when small. We found a significant difference between ruptured and unruptured aneurysms with respect to maximum diameter, aspect ratio, and size ratio. Treatment for small aneurysms should be considered based on size ratio and aspect ratio, not just size.

Influence of size ratio on retreatment after coil embolization for unruptured bifurcation aneurysms

BackgroundAneurysm size is considered a risk factor for aneurysm rupture, and even small aneurysms may rupture, especially bifurcation aneurysms (BAs), which are occasionally detected. Therefore, we aimed to investigate the predictors of retreatment after coil embolization for unruptured BAs, with a particular focus on the absolute and relative size of the aneurysm (size ratio [SR]). MethodsTo evaluate the predictors of retreatment, patients were divided into two groups: those with and those without retreatment. Patient characteristics and radiographic assessments were compared between the groups. SR was defined as the ratio of the maximum aneurysm diameter and the average diameter of the parent artery. ResultsOverall, 181 unruptured BAs in 176 patients were investigated. The mean age of the patients was 63.8 ± 9.6 years. The mean aneurysm size and SR were 7.18 ± 2.94 mm and 2.49 ± 1.32, respectively. Further, 12 aneurysms with retreatment (6.6 %) and 169 aneurysms without retreatment were compared. In univariate analysis, SR was significantly higher in the group with retreatment (P = 0.02), but aneurysm size was not significantly different between the groups (P = 0.09). Multivariable analysis revealed that SR > 2.6 was a significant predictor of retreatment (P = 0.03; odds ratio: 10.41; 95 % confidence interval: 2.1–51.73). ConclusionsThis study showed that SR influences retreatment after coil embolization for unruptured BAs. Therefore, if the aneurysm size and parent artery diameter were small, as in cases with a large SR, meticulous follow-up after coil embolization is required to detect recurrence and recanalization.

Endovascular Treatment of Small Anterior Communicating Artery Aneurysms: Safety and Efficacy in a Contemporary Cohort.

Endovascular treatment (EVT) of small anterior communicating artery (ACoA) aneurysms accompanies a high risk of intraprocedural rupture (IR) because of anatomic location and aneurysm orientation. In this study, we aimed to investigate the safety and efficacy of EVT for small ACoA aneurysms in a contemporary cohort. ACoA aneurysms treated at the Medical University of South Carolina between April 2012 and March 2022 were retrospectively analyzed. Periprocedural baseline characteristics, aneurysm size, and clinical and radiological outcomes were collected. Aneurysms were dichotomized into <4 and ≥4 mm in maximum size. The IR rate, favorable occlusion rate (Raymond-Roy I and II), and the favorable outcome defined as modified Rankin Scale 0-2 were compared. A total of 174 patients were identified, of whom 111 (63.8%) were female, and the median age was 57.7 (interquartile range 50.6-69.6) years. 98 (56.3%) aneurysms were ruptured, and 53 (30.5%) were <4 mm. IR was not observed in unruptured ACoA aneurysms, and there was no significant difference in the IR rates between <4 mm and ≥4 mm ruptured aneurysms (6.5% vs 4.5%, P = .65). Favorable occlusion rate and favorable outcome were observed in 94.7% and 78.2% of patients, respectively. EVT of small ACoA aneurysms is safe and effective.

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.

Subarachnoid Hemorrhage Because of Ruptured Multiple Peripheral Fusiform Aneurysms Associated With Systemic Lupus Erythematosus: A Case Report

BACKGROUND AND IMPORTANCE: In rare cases, systemic lupus erythematosus (SLE) can cause subarachnoid hemorrhage (SAH) because of aneurysm rupture. Such aneurysms are most commonly located in the posterior circulatory system, but can occur extremely rarely in the spinal vascular territory. CLINICAL PRESENTATION: We describe a patient with SLE who had a sudden onset of posterior neck pain. Cranial computed tomography and MRI showed SAH, but no aneurysm could be identified on computed tomography angiography or magnetic resonance angiography. Digital subtraction angiography (DSA) revealed multiple small fusiform aneurysms in the spinal vascular territory, which were treated conservatively without rebleeding. One year later, the patient suffered from recurrent SAH. On DSA, the fusiform aneurysms seen at the previous admission had disappeared and a de novo small fusiform aneurysm was observed in the anterior spinal artery. Conservative treatment was performed, and rebleeding was not observed thereafter. On follow-up DSA performed 2 weeks later, the aneurysm had decreased in size. CONCLUSION: In SLE, spinal arteriography should be performed to evaluate the possible development of peripheral fusiform aneurysms in the spinal vascular territory associated with vasculitis, and careful follow-up is necessary considering the risk of rebleeding because of de novo aneurysms.

Clinical manifestations and outcomes associated with PICU admission in children with multisystem inflammatory syndrome in Taiwan: A retrospective cohort study.

Multisystem inflammatory syndrome in children (MIS-C) is a rare and serious systemic inflammatory disorder that occurs following a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aims to investigate the clinical manifestations, risk factors associated with pediatric intensive care unit (PICU) admission, and outcome among children with MIS-C in Taiwan. A retrospective analysis was conducted among pediatric patients diagnosed with MIS-C between June 2022 and February 2023 at Chang Gung Memorial Hospital, Linkou, Taiwan. Data on demographics, clinical features, laboratory findings, treatment modalities, and outcomes were collected and analyzed. Twenty-eight MIS-C patients, including 9 boys and 19 girls, with an average age of 5.3 ± 3.8 years old, were enrolled. Most of the cases (78.6%) were diagnosed following the first pandemic wave of COVID-19 in Taiwan. The leading clinical manifestations observed were fever (100%), skin rash (64.3%), tachycardia (46.4%), and vomiting (46.4%). Nine patients (32.1%) were admitted to the PICU due to hypotension or neurological manifestations. Higher levels of band-form white blood cells, procalcitonin, ferritin, d-dimer, prothrombin time, NT-proBNP, and lower platelet levels on arrival were associated with PICU admission (p = 3.9 × 10-2 ,9 × 10-3 , 4 × 10-3 ,1 × 10-3 , 5 × 10-3 , 4.1 × 10-2 , and 3.4 × 10-2 , respectively). Arrhythmia in one case (3.5%) and coronary artery abnormalities, including dilatation in two cases (7.1%) and small aneurysms in one case (3.5%) were identified. Regardless of ICU admission, no patients experienced systolic dysfunction or mortality following treatment. MIS-C cases in Taiwan have a favorable outcome. Although one-third of the patients required PICU admission, none of the MIS-C cases resulted in severe cardiovascular morbidity or mortality. This study provides valuable insights into the clinical manifestations and outcomes associated with PICU admission in children with MIS-C in Taiwan.

Quantitative Evaluation of Hemodynamic Changes After Multiple Intracranial Aneurysms Occlusion Using Computational Fluid Dynamics

OBJECTIVEMultiple intracranial aneurysms (MIA) are prevalent. This study conducted hemodynamic calculations on MIA to analyze the effects of occlusion of the internal carotid artery (ICA) and middle cerebral artery (MCA) aneurysms on the hemodynamics of other arteries, as well as the issue of the treatment order for these aneurysms. METHODSThe models of 9 patients with MIA were selected for the study. A computational fluid dynamics model combining 1-D and 3-D was used to obtain the vascular flow pattern and wall pressure. RESULTSThere was increased pressure at the MCA and Anterior Cerebral Artery (ACA) after occlusion of the aneurysm at the ICA. However, the pressure at the ICA has hardly changed after the aneurysm occlusion at the MCA. Occlusion of the aneurysm of different sizes at the MCA had almost no impact on the pressure at the ICA and ACA. For small aneurysm, the pressure of the ACA and MCA increases with decreasing size of the aneurysm at the ICA. After occlusion of a large aneurysm at the ICA, the impact on the pressure of the ACA and MCA is almost the same as after occlusion of a medium-sized aneurysm. CONCLUSIONSIf the treatment order of ICA and MCA aneurysms cannot be determined based on patient factors and aneurysm characteristics, the MCA aneurysm should be treated as a priority.

Abstract 15148: How Reassuring is an Initial Echocardiogram With Normal Coronary Arteries for Patients Presenting With Acute Kawasaki Disease?

Background: We sought to determine the utility of current echocardiography surveillance recommendations for coronary artery (CA) involvement for children with Kawasaki disease (KD) with normal baseline studies. Methods: The International KD Registry enrolled 1200 patients (36 sites, 7 countries) with a site diagnosis of KD from 01/2020 to 01/2023; 139 with positive/possible COVID-19 infection/exposure and 174 with no echo within 10 days of admission were excluded, leaving 887 patients for analysis of results of serial echos and associated factors. Results: An initial echo was performed within 5 days of admission for 96% and within 10 days of symptom onset for 83% of patients; the max Z score in any CA branch at initial echo was normal (Z &lt;2) 78.9%, dilation (Z 2-&lt;2.5) 6.6%, small aneurysm (CAA; Z 2.5-&lt;5) 10.5%, medium CAA (Z 5-&lt;10) 2.9% and large CAA (Z ≥10) for 1.2% of patients. Higher CA Z score/Z score category were both significantly related to greater time from symptom onset to echo (p&lt;0.001). For those with initial normal CAs, a second echo (median of 16 days after admission) was normal for 94.2%, dilation 1.9%, small CAA 2.7%, medium CAA 0.6%, and large CAA for 0.6%. For those with 2 normal echos, a third echo (median of 44 days after admission) was normal for 97.6%, dilation 1.4%, small CAA 0.5%, and 1 patient each with medium and large CAA. Additionally, after up to 6 normal echos, 3 patients had developed small CAA, 1 medium and 1 large CAA. Overall, a total of 24 (2.8%) patients had large CAA (13 admitted &gt;10 days after symptom onset). Of these, 10 had large CAA evident at initial echo performed at day 0-3 after admission, 9 had lesser involvement at initial echo that then progressed to large CAA, and 5 had normal initial and subsequent echos and then were noted to have large CAA at an echo performed 14, 17, 21, 23 and 53 days after admission (the patient with a large CAA first detected at 53 days had no interim echos performed since their first normal echo). Conclusions: Current recommendations for serial echo assessment are effective in detecting all patients with large CAA. For rare patients, despite a normal initial echo large CAA may nonetheless develop. Additionally, important CA involvement may be evident at presentation (often delayed presentation), precluding prevention.

Next-Generation Sequencing of microRNAs in Small Abdominal Aortic Aneurysms: MiR-24 as a Biomarker

Small abdominal aortic aneurysms (AAAs) are asymptomatic but can potentially lead to rupture if left undetected. To date, there is a lack of simple nonradiologic routine tests available for diagnosing AAAs. MicroRNAs (miRNAs) have been proven to be good-quality biomarkers in several diseases, including AAA. An attempt to identify a panel of circulating miRNAs with differential expression in AAAs via next-generation sequencing (NGS) was performed in serum samples: small AAAs (n=3), large AAAs (n=3), and controls (n=3). For miR-24, validation with real-time polymerase chain reaction (PCR) was undertaken in a larger group (n=80). In the NGS study, 23 miRNAs were identified as differentially expressed (with statistical significance) in small AAAs in comparison with controls. Among them, miR-24 showed the largest upregulation with 23-fold change (log2FC 4.5, P=0.024). For large AAAs compared with controls, and small AAAs compared with large AAAs, a panel of 33 and 131 miRNAs showed statistically significant differential expression, respectively. Based on the results of the NGS stage, a literature search was performed, and information regarding AAA pathogenesis, coronary artery disease, and peripheral arterial disease was documented where applicable: miR-24, miR-103, miR-193a, miR-486, miR-582, and miR-3663. Of these 6 miRNAs, miR-24 was chosen for further validation with real-time PCR. Additionally, in the NGS study analysis, 17 miRNAs were common between the small-large AAAs, small AAAs-controls, and large AAAs-controls comparisons: miR-7846, miR-3195, miR-486-2, miR-3194, miR-5589, miR-1538, miR-3178, miR-4771-1, miR-5695, miR-6504, miR-1908, miR-6823, miR-3159, miR-23a, miR-7853, miR-496, and miR-193a. Interestingly, in the validation stage with real-time PCR, miR-24 was found downregulated in small and large AAAs compared with controls (fold-changes: 0.27, P=0.015 and 0.15, P=0.005, respectively). No correlation was found between average Ct values, aneurysm diameter, and patients' age. Our findings further highlight the importance of miR-24 as a potential biomarker as well as a therapeutic target for abdominal aneurysmal disease. Future research and validation of a panel of miRNAs for AAA would aid in diagnosis and discrimination between diseases with overlapping pathogeneses.

Abstract 172: Outcomes and Complications of Stent‐Assisted Aneurysm Repair in Acute Subarachnoid Hemorrhage

Introduction The use of detachable coils for endovascular embolization of cerebral aneurysms has become a safe and effective alternative to direct surgical clipping in patients with ruptured aneurysmal subarachnoid hemorrhage. However, endovascular treatment of wide‐necked, large (&gt;10 mm), and complex ruptured aneurysms continues to remain challenging despite multiple technical advancements in recent years. In order to improve treatment outcomes in these difficult cases, the use of stent‐assisted embolization has been attempted in endovascular treatment of intracranial aneurysms. In order to avoid thromboembolic complications in these cases, patients require treatment with antiplatelet therapy. Previous studies have shown that antiplatelet therapy poses an increased risk of hemorrhagic complications; this risk might be further heightened in the setting of acute subarachnoid hemorrhage (SAH), as these patients can develop an abnormal coagulation status. The purpose of this study was to retrospectively analyze the results and complications associated with stent‐assisted embolization of intracranial aneurysms in the acute treatment of subarachnoid hemorrhage at Dell Seton Medical Center. Methods Data from patients with acutely‐ruptured intracranial aneurysm treated with stent‐assisted embolization at Dell Seton Medical Center in the period between 2021 and 2022 were retrospectively assessed, with the focus of addressing aneurysm occlusion, clinical outcomes and complications. Results Fifteen patients with ruptured intracranial aneurysms were included in the analysis. Post‐procedural re‐rupture and hemorrhagic complications were observed in three patients, leading to death in two patients. Thromboembolic complications were observed in one patient, with the clinical outcome of death due to basilar stent thrombosis. Immediate complete occlusion and occlusion with residual neck was achieved in 66.7% of cases. Conclusion In the case of ruptured intracranial aneurysms with large and complex morphology and a wide neck, the use of stent‐assisted repair may be necessary compared to simpler and smaller aneurysms that can be treated with coils alone. The use of stent‐assisted repair in acutely‐ruptured aneurysms in this series of cases demonstrated rapid and good aneurysmal occlusion. The post‐procedural complication rate proved to be higher than in non‐ruptured stent‐assisted coiling. However, the overall resulting morbidity and mortality rates in this cohort of patients is lower than could have been expected; furthermore, the complication rates found in this study are in line with those reported in similar studies. In most cases in the emergency setting, it is not possible to appropriately prepare a patient with antiplatelet therapy pre‐procedurally. As a result, the proper antiplatelet medication regimen and its appropriate timing continue to remain a significant topic of investigation. In addition, there continues to be further investigation into the optimal timing of intervention to minimize risk of peri‐procedural and post‐procedural complications. Further retrospective analysis of patient data over multiple years and across multiple centers is needed to better assess outcomes and complications of stent‐assisted aneurysm repair in acute subarachnoid hemorrhage.

Editor's Choice – External Validation of a Prognostic Model for Survival of Patients With Abdominal Aortic Aneurysms Treated by Endovascular Aneurysm Repair

Current guidelines recommend diameter monitoring of small and asymptomatic abdominal aortic aneurysms (AAAs) due to the low risk of rupture. Elective AAA repair is recommended for diameters ≥ 5.5 cm in men and ≥ 5.0 cm in women. However, data supporting the efficacy of elective treatment for all patients above these thresholds are diverging. For a subgroup of patients, life expectancy might be very short, and elective AAA repair at the current threshold may not be justified. This study aimed to externally validate a predictive model for survival of patients with asymptomatic AAA treated with endovascular aneurysm repair (EVAR). This was a multicentre international retrospective observational cohort study. Data were collected from four European aortic centres treating patients between 2001 and 2021. The initial model included age, estimated glomerular filtration rate (eGFR), and chronic obstructive pulmonary disease (COPD) as independent predictors for survival. Model performance was measured by discrimination and calibration. The validation cohort included 1 500 patients with a median follow up of 65 months, during which 54.6% of the patients died. The external validation showed slightly decreased discrimination ability and signs of overfitting in model calibration. However, a high risk subgroup of patients with impaired survival rates was identified: octogenarians with eGFR < 60 OR COPD, septuagenarians with eGFR < 30, and septuagenarians with eGFR < 60 and COPD having survival rates of only 55.2% and 15.5% at five and 10 years, respectively. EVAR is a valuable treatment option for AAA, especially for patients unsuitable for open repair. Nonetheless, not all these patients will benefit from EVAR, and an individualised treatment recommendation should include considerations on life expectancy. This study provides a risk stratification to identify patients who may not benefit from EVAR under the present diameter threshold.

Systematic Review and Meta-Analysis of the Incidence of Rupture, Repair, and Death of Small and Large Abdominal Aortic Aneurysms under Surveillance.

The ultimate goal of treating patients with abdominal aortic aneurysms (AAAs) is to repair them when the risk of rupture exceeds the risk of repair. Small AAAs demonstrate a low rupture risk, and recently, large AAAs just above the threshold (5.5-6.0 cm) seem to be at low risk of rupture as well. The present review aims to investigate the outcomes of AAAs under surveillance through a comprehensive systematic review and meta-analysis. PubMed, Embase, and the Cochrane Central Register were searched (22 March 2022; PROSPERO; #CRD42022316094). The Cochrane and PRISMA statements were respected. Blinded systematic screening of the literature, data extraction, and quality assessment were performed by two authors. Conflicts were resolved by a third author. The meta-analysis of prevalence provided estimated proportions, 95% confidence intervals, and measures of heterogeneity (I2). Based on I2, the heterogeneity might be negligible (0-40%), moderate (30-60%), substantial (50-90%), and considerable (75-100%). The primary outcome was the incidence of AAA rupture. Secondary outcomes included the rate of small AAAs reaching the threshold for repair, aortic-related mortality, and all-cause mortality. Fourteen publications (25,040 patients) were included in the analysis. The outcome rates of the small AAA group (<55 mm) were 0.3% (95% CI 0.0-1.0; I2 = 76.4%) of rupture, 0.6% (95% CI 0.0-1.9; I2 = 87.2%) of aortic-related mortality, and 9.6% (95% CI 2.2-21.1; I2 = 99.0%) of all-cause mortality. During surveillance, 21.4% (95% CI 9.0-37.2; I2 = 99.0%) of the initially small AAAs reached the threshold for repair. The outcome rates of the large AAA group (>55 mm) were 25.7% (95% CI 18.0-34.3; I2 = 72.0%) of rupture, 22.1% (95% CI 16.5-28.3; I2 = 25.0%) of aortic-related mortality, and 61.8% (95% CI 47.0-75.6; I2 = 89.1%) of all-cause mortality. The sensitivity analysis demonstrated a higher rupture rate in studies including <662 subjects, patients with a mean age > 72 years, >17% of female patients, and >44% of current smokers. The rarity of rupture and aortic-related mortality in small AAAs supports the current conservative management of small AAAs. Surveillance seems indicated, as one-fifth reached the threshold for repair. Large aneurysms had a high incidence of rupture and aortic-related mortality. However, these data seem biased by the sparse and heterogeneous literature overrepresented by patients unfit for surgery. Specific rupture risk stratified by age, gender, and fit-for-surgery patients with large AAAs needs to be further investigated.

A Systematic Review of Deep-Learning Methods for Intracranial Aneurysm Detection in CT Angiography.

Background: Subarachnoid hemorrhage resulting from cerebral aneurysm rupture is a significant cause of morbidity and mortality. Early identification of aneurysms on Computed Tomography Angiography (CTA), a frequently used modality for this purpose, is crucial, and artificial intelligence (AI)-based algorithms can improve the detection rate and minimize the intra- and inter-rater variability. Thus, a systematic review and meta-analysis were conducted to assess the diagnostic accuracy of deep-learning-based AI algorithms in detecting cerebral aneurysms using CTA. Methods: PubMed (MEDLINE), Embase, and the Cochrane Library were searched from January 2015 to July 2023. Eligibility criteria involved studies using fully automated and semi-automatic deep-learning algorithms for detecting cerebral aneurysms on the CTA modality. Eligible studies were assessed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. A diagnostic accuracy meta-analysis was conducted to estimate pooled lesion-level sensitivity, size-dependent lesion-level sensitivity, patient-level specificity, and the number of false positives per image. An enhanced FROC curve was utilized to facilitate comparisons between the studies. Results: Fifteen eligible studies were assessed. The findings indicated that the methods exhibited high pooled sensitivity (0.87, 95% confidence interval: 0.835 to 0.91) in detecting intracranial aneurysms at the lesion level. Patient-level sensitivity was not reported due to the lack of a unified patient-level sensitivity definition. Only five studies involved a control group (healthy subjects), whereas two provided information on detection specificity. Moreover, the analysis of size-dependent sensitivity reported in eight studies revealed that the average sensitivity for small aneurysms (<3 mm) was rather low (0.56). Conclusions: The studies included in the analysis exhibited a high level of accuracy in detecting intracranial aneurysms larger than 3 mm in size. Nonetheless, there is a notable gap that necessitates increased attention and research focus on the detection of smaller aneurysms, the use of a common test dataset, and an evaluation of a consistent set of performance metrics.

Ascending Aortic Surgery for Small Aneurysms in Men and Women.

According to recent data, thoracic aortic surgery has reduced morbidity and mortality including ascending aortic aneurysm treatment; however, women are at increased postoperative risk of adverse outcomes. Our aim was to evaluate early and late outcomes in male and female patients who underwent pre-emptive ascending aortic replacement (AAR). From January 2013 to September 2021, 91 patients (56 [61.5%] men and 35 [38.5%] women) underwent AAR for small (ranged from 5.0 to 5.5 cm) non-syndromic aneurysms. A propensity score-based adjustment of the groups was performed. We compared clinical outcomes between males and females. Preoperative normalized aortic diameters were significantly larger in females (2.9 [2.7; 3.2] cm/m2) than in males (2.5 [2.3; 2.6] cm/m2, P<0.001), without differences in absolute values (51 [49; 53] mm vs. 52 [50; 53] mm, P=0.356). There were no significant differences in neurological, cardiac, pulmonary, and renal complications in both groups before and after matching. In-hospital mortality was 1 (1.8%) and 2 (5.7%) (P=0.307) in male and female patients in unmatched groups and 1 (2.9%) and 2 (5.7%) (P=0.553) in matched groups, respectively. Univariate logistic regression analysis revealed that the only risk factor for in-hospital mortality was age (odds ratio 1.117, 95% confidence interval 1.003-1.244; P=0.04). The overall survival rate was 83.5±0.06% in men and 94.3±0.04% in women at 36 months (P=0.404). Ascending aortic surgery for aneurysms ranged from 5.0 to 5.5 cm seems to have tolerable early and late outcomes in men and women.

Safety and efficacy of the pipeline embolization device for treatment of small vs. large aneurysms: a systematic review and meta-analysis.

Flow diversion with the pipeline embolization device (PED) is increasingly used to treat intracranial aneurysms with high obliteration rates and low morbidity. However, long-term (≥ 1year) angiographic and clinical outcomes still require further investigation. The aim of this study was to compare the occlusion and complication rates for small (< 10mm) versus large (10-25mm) aneurysms at long-term following treatment with PED. A systematic review and meta-analysis were performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We conducted a comprehensive search of English language databases including Ovid MEDLINE and Epub Ahead of Print, In-Process, and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Our studies included a minimum of 10 patients treated with PED for small vs. large aneurysms and with at least 12months of follow-up. The primary safety endpoint was the rate of clinical complications measured by the occurrence of symptomatic stroke (confirmed clinically and radiographically), intracranial hemorrhage, or aneurysmal rupture. The primary efficacy endpoint was the complete aneurysm occlusion rate. Our analysis included 19 studies with 1277 patients and 1493 aneurysms. Of those, 1378 aneurysms met our inclusion criteria. The mean age was 53.9years, and most aneurysms were small (89.75%; N = 1340) in women (79.1%; N = 1010). The long-term occlusion rate was 73% (95%, CI 65 to 80%) in small compared to 84% (95%, CI 76 to 90%) in large aneurysms (p < 0.01). The symptomatic thromboembolic complication rate was 5% (95%, CI 3 to 9%) in small compared to 7% (95%, CI 4 to 13%) in large aneurysms (p = 0.01). The rupture rate was 2% vs. 4% (p = 0.92), and the rate of intracranial hemorrhage was 2% vs. 4% (p = 0.96) for small vs. large aneurysms, respectively; however, these differences were not statistically significant. The long-term occlusion rate after PED treatment is higher in large vs. small aneurysms. Symptomatic thromboembolic rates with stroke are also higher in large vs. small aneurysms. The difference in the rates of aneurysm rupture and intracranial hemorrhage was insignificant. Although the PED seems a safe and effective treatment for small and large aneurysms, further studies are required to clarify how occlusion rate and morbidity are affected by aneurysm size.

Navigating complexity: a comprehensive review of microcatheter shaping techniques in endovascular aneurysm embolization

The endovascular intervention technique has gained prominence in the treatment of intracranial aneurysms due to its minimal invasiveness and shorter recovery time. A critical step of the intervention is the shaping of the microcatheter, which ensures its accurate placement and stability within the aneurysm sac. This is vital for enhancing coil placement and minimizing the risk of catheter kickback during the coiling process. Currently, microcatheter shaping is primarily reliant on the operator's experience, who shapes them based on the curvature of the target vessel and aneurysm location, utilizing 3D rotational angiography or CT angiography. Some researchers have documented their experiences with conventional shaping methods. Additionally, some scholars have explored auxiliary techniques such as 3D printing and computer simulations to facilitate microcatheter shaping. However, the shaping of microcatheters can still pose challenges, especially in cases with complex anatomical structures or very small aneurysms, and even experienced operators may encounter difficulties, and there has been a lack of a holistic summary of microcatheter shaping techniques in the literature. In this article, we present a review of the literature from 1994 to 2023 on microcatheter shaping techniques in endovascular aneurysm embolization. Our review aims to present a thorough overview of the various experiences and techniques shared by researchers over the last 3 decades, provides an analysis of shaping methods, and serves as an invaluable resource for both novice and experienced practitioners, highlighting the significance of understanding and mastering this technique for successful endovascular intervention in intracranial aneurysms.

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.

Microsurgical strategies for small unruptured dorsal internal carotid artery aneurysms.

This study aimed to develop microsurgical strategies based on the anatomical relationship between dorsal internal carotid artery (ICA) aneurysms, the falciform ligament (FL), and the anterior clinoid process (ACP). Between 2017 and 2022, 25 patients with unruptured dorsal ICA aneurysms (less than 4 mm in diameter) underwent microsurgical direct clipping. These cases involved the left ICA (n=17) and the right ICA (n=8), with a mean aneurysm size of 3.3 mm (range, 2.5 to 4 mm). We used computed tomography angiography (CTA) and digital subtraction angiography to elucidate the anatomical relationship between dorsal ICA aneurysms and other structures. All procedures involved an ipsilateral pterional approach with securement of the ipsilateral cervical ICA for proximal control. Among the 25 dorsal ICA aneurysms, 8 (32%) were clipped without the FL being incised. Another 5 (20%) were clipped solely after the FL was cut. For the remaining 12 cases, the aneurysms were successfully clipped following FL incision and partial ACP removal. Patients exhibited favorable postoperative recoveries with good outcomes, and postoperative CTA revealed complete aneurysm clipping without any residual remnants. Conclusions: We were able to perform clipping without removing the ACP in 13 patients (52%), and in 8 of these (32%), the clipping was carried out directly without cutting the FL. Microsurgery, coupled with proximal control of the cervical ICA, can serve as a viable alternative for patients with small dorsal ICA aneurysms, especially when endovascular treatment options are limited, and 3D CTA confirms a clear anatomical relationship with the ACP.

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.

Ruptured brainstem arteriovenous malformation associated with a thalamoperforating artery aneurysm arising from the P1 segment of the right posterior cerebral artery: illustrative case.

Cerebral aneurysms of perforating arteries are rare and can be difficult to detect on computed tomography angiography (CTA) and digital subtraction angiography. Treatment is challenging and associated with a significant risk of morbidity. Endovascular treatment of a thalamoperforating artery (TPA) aneurysm within the midbrain has not previously been reported. A 13-year-old girl with no previous medical history presented with unconsciousness and anisocoria. Head computed tomography showed a right midbrain hemorrhage. CTA showed a midbrain arteriovenous malformation fed by a TPA aneurysm arising from the P1 segment of the right posterior cerebral artery. The feeder had a small distal aneurysm, which increased in size over time. Endovascular embolization was then performed. Cerebral aneurysms of perforating arteries are rare and can be difficult to treat. This is the first report of the endovascular treatment of a TPA aneurysm within the midbrain. Understanding the individual patient's brainstem perforator anatomy and the associated blood flow is essential before occluding a TPA aneurysm to avoid causing ischemia or infarction. Arteriovenous malformation embolization within the brainstem should be avoided because of interperforator anastomoses.