Anterior Circulation Intracranial Aneurysms Research Articles

Comparative analysis of supra-orbital keyhole approach and pterional approach for surgical clipping of intracranial anterior circulation aneurysms in patients with favorable Hunt and Hess grades

IntroductionTraditional large craniotomies have been the standard for aneurysm surgery. However, minimally invasive “keyhole” approaches have gained popularity for aneurysm clipping in recent years. This study focuses on Supra-Orbital Keyhole Approach (SOKHA),its use in clipping of aneurysms of the anterior Circle of Willis. Here we share the experiences of a tertiary care center regarding aneurysm clipping using SOKHA. Materials and methodsWe retrospectively reviewed 166 cases involving aneurysm clipping, with 62 patients undergoing SOKHA and 104 patients undergoing the pterional approach. Factors evaluated included patient demographics, aneurysm characteristics, incidence of intraoperative complications, temporary-clipping usage, and postoperative clinical outcomes. Glasgow Outcome Scale scores were utilized to assess clinical outcomes. ResultsThe study found that both the SOKHA and pterional approaches were similar in terms of age distribution, Hunt and Hess grades, and the incidence of hydrocephalus. The majority of aneurysms in both groups were anterior communicating artery aneurysms.Hydrocephalus was observed in 14.5 % of SOKHA cases and 13.5 % of pterional cases. Intraoperative aneurysm rupture occurred in 8.1 % of SOKHA cases and 7.7 % of pterional cases. There were no mortalities in the SOKHA group, while the pterional group had 1.92 % mortality rate. At the last follow-up, 77.4 % of SOKHA cases and 75.9 % of pterional cases had a favorable outcome (Glasgow Outcome Scale IV and V), with no significant difference. ConclusionSOKHA offers the advantage of potential cosmetic benefit with neurological outcomes comparable to those of the traditional pterional approach, in properly selected patients.

Treatment Strategy of Intracranial Anterior Circulation Aneurysm Presenting with Cerebral Ischemia: A Single-Center Experience.

To investigate the clinical characteristics and treatment strategy of anterior circulation aneurysm presenting with cerebral ischemia. We performed a retrospective review of patients with intracranial anterior circulation aneurysms presenting with cerebral ischemia examined in the Fifth Ward of the Neurosurgery Department of Tianjin Huanhu Hospital between September 2016 and September 2023. Data were reviewed for age, sex, presentation, type and size, location, treatment modalities, postoperative complications, clinical and imaging outcomes, and follow-up outcomes. Among the 13 patients, there were 8 males and 5 females (1.6:1). Their presentations included ischemic stroke (69.23%, 9/13) and transient ischemic attack (TIA) (30.77%, 4/13). The aneurysms were dissecting (46.15%, 6/13), saccular (30.77%, 4/13), and saccular combined with thrombosis (23.08%, 3/13) in shape. There were 6 giant aneurysms, 4 large aneurysms, and 3 microaneurysms. Three (23.08%, 3/13) aneurysms were located at the internal carotid artery (ICA) and 10 (76.92%, 10/13) were located in the middle cerebral artery (MCA). A preoperative magnetic resonance perfusion (MRP) examination was performed in all patients, and 9 (69.23%, 9/13) patients showed hypoperfusion. Treatment modalities included stent-assisted embolization, direct clipping, clipping combined with bypass, resection combined with bypass, isolated combined with bypass, proximal occlusion combined with bypass, and the internal carotid artery constriction combined with bypass. Twelve (92.31%, 12/13) patients had no postoperative complications, and temporary complications occurred in 1 (7.69%, 1/13) patient. Aneurysms disappeared in 11 cases and shrank in 2 cases postoperatively. All patients were followed up for 1 to 72 months. We found no new cerebral infarction, no subarachnoid hemorrhage, and no recurrence or enlargement of aneurysms during the follow-up. Intracranial anterior circulation aneurysm presenting with cerebral ischemia is rare. Saccular aneurysms with wide neck or thrombosis and dissected aneurysms of the anterior circulation may result in cerebral ischemic attack caused by distal vascular embolism. Individualized treatment should be performed, and cerebral revascularization is an effective treatment for patients with intracranial anterior circulation aneurysms presenting with cerebral ischemia.

Sexual Dysfunction after Clipping of Ruptured Intracranial Aneurysms.

Sexual dysfunction significantly affects interpersonal relationships and overall quality of life. It remains a matter of concern for risk assessment and counseling in patients with ruptured intracranial aneurysms. To assess the sexual dysfunctions in patients undergoing clipping for ruptured intracranial aneurysms and comparative evaluation among different anterior circulation aneurysms. We prospectively included 40 male patients of ruptured intracranial aneurysms of anterior circulation (age range: 20-60 years; sexually active preoperatively), managed with craniotomy and clipping. We evaluated the sexual outcome in patients with excellent Glasgow outcome score (GOS) five at a minimum one year of follow-up. Patients with GOS-5 status at follow-up were broadly classified into two groups: Anterior communicating artery aneurysm (Acom), and non-Acom) aneurysms. We valued sexual outcome with Subjective Sexual Arousal Scale for Men at follow-up, and compared in the two groups. Mean age of patients was 44.78 ± 9.51 years. Besides 20 Acom aneurysms, other groups included 11 middle cerebral artery aneurysms, five internal carotid artery aneurysms, three posterior communicating artery aneurysms, and one distal anterior cerebral artery aneurysm. The mean follow-up was 24.45 ± 13.58 months. Patients with non-Acom aneurysms had an overall better outcome in the sexual performance domain "P = 0.015," mental satisfaction domain "P = 0.009," and sexual assertiveness domain "P = 0.007." However, there was no statistical difference in partner communication domain "P = 0.593," and partner relationship domain "P = 0.378." Overall, the sexual outcome was inferior in patients treated for Acom aneurysms compared to other anterior circulation aneurysms. In cases of aneurysmal subarachnoid hemorrhage, sexual dysfunctions are common even after good clinical outcomes. The study revealed prominent differences in outcomes on the sexual quality of life in patients harboring Acom aneurysms as compared to anterior circulation aneurysms located off-midline.

Anterior circulation location-specific results for stent-assisted coiling – carotid versus distal aneurysms: 1-year outcomes from the Neuroform Atlas Stent Pivotal Trial

BackgroundThe Neuroform Atlas Stent System is an established treatment modality for unruptured anterior and posterior circulation intracranial aneurysms. Location-specific results are needed to guide treatment decision-making. However, it is unclear...

Abstract 038: Fusiform/Dissecting vs. Saccular Posterior Circulation Aneurysms Treated with Flow Diversion: A Multicenter Study

Introduction Flow diverters have demonstrated reliable safety and effectiveness for the treatment of selected anterior circulation intracranial aneurysms. However, posterior circulation aneurysms comprise around 10‐15% of all aneurysms, and they frequently present atypical morphological and anatomical characteristics. Furthermore, these lesions have an increased risk of rupture (compared to those in the anterior circulation) with respect to size and higher treatment risks (regardless of the technique). Flow diversion in posterior circulation aneurysms has been described previously with inconsistent clinical and radiological results. Hence, we aimed to compare the safety and effectiveness of FDs in fusiform/dissecting vs. saccular aneurysms located in the vertebrobasilar vessels. Methods We performed a multicenter, retrospective cohort study including 9 centers. All patients treated with FDs for aneurysms located in the posterior circulation (vertebral and basilar arteries) between 2015 and 2022 were included. Patients were divided into two groups according to the morphology of the aneurysm (fusiform/dissecting vs. saccular). The effectiveness outcome was complete aneurysm occlusion (Raymond‐Roy Class 1) at the latest follow‐up. Safety outcomes included the incidence of ischemic/hemorrhagic and mortality. After adjusting for confounders multivariable logistic regressions were performed to compare outcomes of interest. Results A total of 147 patients with 147 aneurysms were included. The fusiform/dissecting group included 85 cases, while the saccular group 62. The saccular group had older patients (median age: fusiform/dissecting, 55 years [45‐64] vs. saccular, 63 years [51‐70.0]; p=.02). The number of female patients was not different between groups (fusiform/dissecting, 42% vs. saccular, 58%; p=.05). Clinical presentation, comorbidities, modified Fisher, and Hunt and Hess were similar. Baseline modified Rankin Score (mRS) was different (mRS 0‐2: fusiform/dissecting, 84% vs. saccular, 98%; p=.030). Previous endovascular treatment (p=.396) was similar. Aneurysm location (most were in the vertebral artery: fusiform/dissecting, 60% vs. saccular, 42%; p=.009) was different. Median aneurysm size (fusiform/dissecting, 10.0 mm [6.5‐18.8] vs. saccular, 5.9 [3.0‐10.0]; p=<.001), and proximal (fusiform/dissecting, 3.6 mm [2.7‐4.1] vs. saccular, 2.8 [2.4‐3.3]; p=<.001) and distal landing (fusiform/dissecting, 3.2 mm [2.5‐3.5] vs. saccular, 2.4 [2.0‐3.0]; p=<.001) zones were different. The number of FDs per patient (>1 FD: fusiform/dissecting, 36% vs. saccular, 10%; p=<.001) and adjunctive coiling (fusiform/dissecting, 89% vs. non‐F, 74%; p= .015) were different. The most commonly implanted was Pipeline Flex (fusiform/dissecting, 55%, vs. saccular, 40%). Thromboembolic (fusiform/dissecting, 8.2%, vs. saccular, 8.1%; p=.97) and hemorrhagic (fusiform/dissecting, 4%, vs. saccular, 10%; p=.125). Mortality was increased in the fusiform/dissecting group (19%) vs saccular (12%) but not different (p=.365). At an overall median follow‐up time of 13.5 [7.4‐28.8] months, complete occlusion was lower in the fusiform/dissecting group (61% vs. F, 63%) but not statistically different (p=.356). Follow‐up mRS was not different (mRS 0‐2: fusiform/dissecting, 73% vs. saccular, 76%; p=.365). 172 (71%) of the cases achieved complete aneurysm occlusion. Multivariable analysis showed that age (OR: 0.96; 95%CI: 0.93‐0.99; p=.008) and location in the basilar artery (OR: 0.09; 95%CI: 0.03‐0.29; p=<.001) were associated with incomplete occlusion at follow‐up. Conclusion Our results suggest that flow diversion can be an effective treatment for fusiform/dissecting and saccular aneurysms located in the posterior circulation. Although the occlusion rates after flow diversion in fusiform/dissecting aneurysms showed a lower rate compared to saccular, the favorable safety profile of FDs allows them to be considered a valuable tool in the neuroinventionalist armamentarium.

Analysis of independent risk factors for aneurysm rupture based on carotid tortuosity index and morphological parameters of single intracranial aneurysms in anterior circulation

PurposeOur study focused on the risk factors associated with anterior circulation intracranial aneurysm (IA) rupture by examining the carotid artery (CA) tortuosity index (TI) and anterior circulation IA morphological parameters. MethodThis study conducted a retrospective analysis of clinical and imaging data from 163 patients with anterior circulation IA diagnosed by head and neck computed tomography angiography (CTA). The patients were categorized into two groups: the ruptured group (57 cases) and the unruptured group (106 cases). CA was categorized based on its location into three segments: the extracranial segment of the internal carotid artery (EICA) TI, the angle of the internal carotid artery (ICA) and the common carotid artery (CCA) TI. Measure the morphological parameters of all IA: IA length neck (L), IA height (H), aneurysm diameter width (D), the ratio of L to the mean diameter of the IA-bearing artery (SR), the ratio of H to D (AR), the angle of flow inflow (FA) and IA angle (AA). The study conducted five types of analysis to determine the risk factors for anterior circulation IA rupture. The first was an univariate analysis of the risk factors. The second was an analysis of the correlation between CA TI and IA morphological parameters. The third used multivariate logistic stepwise regression analysis to analyse independent risk factors for IA rupture. The fourth was to plot ROC curves to build a predictive model for IA rupture and calculate diagnostic thresholds. Finally, a data set from another hospital (78 cases) was used as a validation set to validate the multivariate model. ResultUnivariate analysis revealed that there were statistically significant differences (P < 0.05) in gender, EICA TI, location of IA and IA morphological parameters (FA, H, AR, L, SR), which acted as risk factors for anterior circulation IA rupture. The results of Spearman correlation analysis indicate that CCA TI is significantly correlated with SR, H and L (P < 0.05), while EICA TI is significantly correlated with FA and L (P < 0.05). The results of multivariate logistic analysis showed that FA (OR = 1.072, 95%CI = 1.04–1.10, P < 0.001), SR (OR = 4.949, 95%CI = 1.96–12.53, P = 0.001), EICA TI (OR = 1.037, 95%CI = 1.01–1.07, P = 0.003) were independent risk factors for IA rupture. The ROC curve plotting results suggest that the area under the curve (AUC) of FA is 0.860 with a diagnostic threshold of 110.1°; the AUC of SR is 0.786 with a diagnostic threshold of 1.67; the AUC of EICA TI is 0.723 with a diagnostic threshold of 28.845; the AUC of the three combined is 0.903 with a threshold of 0.480. The combined factor diagnostic model is validated according to the validation set, and the results show that the AUC (0.866) of the validation set is not much different from the AUC (0.903) of the multivariate model, and the multivariate model has a better diagnostic effect. ConclusionIn clinical practice, it is important to consider the evaluation of aneurysm rupture in combination with imaging, as FA, SR and ECIA TI are independent risk factors for IA rupture in the anterior circulation. Unlike the IA morphological parameters, EICA TI is an often overlooked extracranial parameter, but is equally important in its power to predict IA rupture. When the EICA TI exceeds 28.845, the IA has the possibility of rupture. Finally, multivariate diagnostic model are of interest when considering rupture of the anterior circulation IA.

Treatment Modalities of Complex Anterior Circulation Intracranial Aneurysms

Background Complex intracranial aneurysms (CIAs) are the most technically demanding neurosurgical pathologies. Although extensive work and effort has been directed to the treatment of these challenging vascular lesions, no formal definition exists on what complex aneurysms are, and it is rather subjective to individual interpretation that an aneurysm receives such label. Aim of the Study The overall aim of the study is to assess the clinical outcomes of the different modalities in management of complex intracranial anterior circulation aneurysms and to try to set up a clear and concrete treatment algorithm for the management dilemma. Patients and Methods This study is a prospective observational study that included 40 patients. All patients were evaluated by an interdisciplinary conference consisting of neuroendovascular surgeons and vascular neurosurgeons for assessment of the therapeutic options and the suitability of endovascular and/or surgical treatment. Initially, study setting was supposed to be in Ain Shams University teaching hospitals, Egypt, King’s College Hospital, United Kingdom and Barrow’s Neurological institute, USA. Unfortunately, due to COVID-19 Pandemic, Cases from King’s College Hospital in London were only included. Results Twenty cases were managed surgically, while 18 were treated by different endovascular techniques. Both surgical and endovascular modalities were used as a hybrid approach to treat 2 cases. Recurrence of treated aneurysms was seen only in the endovascular modality. Four cases out of the 18 cases treated by endovascular techniques showed either residual or recurrence of the previously treated aneurysms. Four documented intervention related mortalities occurred during the first 6 months. Two cases out of the 4 were treated by endovascular techniques (balloon assisted coiling &amp; parent vessel occlusion), one case was surgically treated by clip/wrap technique and the last mortality was seen in a case treated by the hybrid approach (Clipping+ flow diverter). Conclusion Complex intracranial aneurysms managed surgically showed less recurrence rate than those treated by different endovascular techniques. CIAs treated by endovascular modalities showed much lower length of hospital stay and better modified Rankin scale after 6 months. Complications rate and mortality rate were nearly similar in both groups and were usually related to the initial poor presentation with hight WFNS grade upon the initial ictus.

A challenging case of recurrent and progressive fusiform anterior circulation intracranial aneurysms: illustrative case.

Intracranial fusiform aneurysms are circumferential dilations of cerebral arteries that can lead to complications including ischemic stroke due to vessel occlusion, subarachnoid hemorrhage, or intracerebral hemorrhage. Treatment options for fusiform aneurysms have expanded significantly in recent years. Microsurgical treatment options include proximal and distal surgical occlusion and microsurgical trapping of the aneurysm, usually in association with high-flow bypass procedures. Endovascular treatment options include the placement of coils and/or flow diverters. Here the authors report a case of aggressive surveillance and treatment of a man with multiple progressive, recurrent, and de novo fusiform aneurysms of the left anterior cerebral circulation over 16 years. Because the long-term course of his treatment coincided with the recent expansion of endovascular treatment options, he underwent every type of treatment listed above. This case demonstrates the wide range of therapeutic options for fusiform aneurysms and how the treatment model for these lesions has evolved.

Hemodynamics of anterior circulation intracranial aneurysms with daughter blebs: investigating the multidirectionality of blood flow fields

Recent advances in diagnostic neuroradiological imaging, allowed the detection of unruptured intracranial aneurysms (IAs). The shape – irregular or multilobular – of the aneurysmal dome, is considered as a possible rupture risk factor, independently of the size, the location and patient medical background. Disturbed blood flow fields in particular is thought to play a key role in IAs progression. However, there is an absence of widely-used hemodynamic indices to quantify the extent of a multi-directional disturbed flow. We simulated blood flow in twelve patient-specific anterior circulation unruptured intracranial aneurysms with daughter blebs utilizing the spectral/hp element framework Nektar++. We simulated three cardiac cycles using a volumetric flow rate waveform while we considered blood as a Newtonian fluid. To investigate the multidirectionality of the blood flow fields, besides the time-averaged wall shear stress (TAWSS), we calculated the oscillatory shear index (OSI), the relative residence time (RRT) and the time-averaged cross flow index (TACFI). Our CFD simulations suggest that in the majority of our vascular models there is a formation of complex intrasaccular flow patterns, resulting to low and highly oscillating WSS, especially in the area of the daughter blebs. The existence of disturbed multi-directional blood flow fields is also evident by the distributions of the RRT and the TACFI. These findings further support the theory that IAs with daughter blebs are linked to a potentially increased rupture risk.

A Single Flow Re-direction Endoluminal Device for the Treatment of Large and Giant Anterior Circulation Intracranial Aneurysms.

PurposeThe purpose of this study was to report the author’s experiences in treating large (10–25 mm) and giant (>25 mm) intracranial aneurysms (IAs) using a single Flow Re-direction Endoluminal Device (FRED) without assistant coiling, with a focus on procedure-related complications.Materials and MethodsA total of 33 patients who were treated with FRED between January 2018 and July 2020 were retrospectively reviewed. The timing of procedure-related complications was chronologically categorized as acute (within 7 days), subacute (8 to 21 days), and delayed (after 21 days) periods. Follow-up angiography was performed at 2 to 27 months (mean 9.7 months), and clinical follow-up was performed at 1 to 31 months (mean 14.1 months) in all patients.ResultsSix (18.2%) patients experienced procedure-related complications, including 2 (6.1%) in acute period, 1 (3.0%) in subacute period, and 3 (9.1%) in delayed period. Thromboembolic complications occurred in 5 (15.2%) patients and hemorrhagic complications in 1 (3.0%). Permanent morbidity and mortality rates were 3.0% each. Non-internal carotid artery (ICA) location of IAs (odds ratio 6.532; 95% confidence interval, 1.335–17.816; p=0.034) was the only independent risk factor for procedure-related complications on multivariate logistic regression analysis.ConclusionThe procedure-related complication rate was 18.2% in this study. Procedure-related complications might increase when treating large and giant IAs located on a non-ICA, especially on the middle cerebral artery. Therefore, it may be suggested that neurointerventionists and endovascular neurosurgeons should pay attention to the location of IAs when treating large and giant IAs with a single FRED.

Imaging versus Intervention in Managing Small Unruptured Intracranial Aneurysms: A Cost-Effectiveness Analysis

Objective: Current guidelines recommend active surveillance with serial magnetic resonance angiography (MRA) for management of small, asymptomatic unruptured anterior circulation aneurysms (UIAs). We sought to determine the cost-effectiveness of active surveillance compared to immediate surgery. Methods: We developed a Markov cost-effectiveness model simulating patients with small (<7 mm) UIAs managed by active surveillance via MRA, immediate surgery, or watchful waiting. Inputs for the model were abstracted from the literature and used to construct a comprehensive model following persons from diagnosis to death. Outcomes were quality-adjusted life-years (QALYs), lifetime medical costs (2015 USD), and incremental cost-effectiveness ratios (ICERs). Cost-effectiveness, deterministic, and probabilistic sensitivity analyses were performed. Results: Immediate surgical treatment was the most cost-effective management strategy for small UIAs with ICER of USD 45,772 relative to active surveillance. Sensitivity analysis demonstrated immediate surgery was the preferred strategy, if rupture rate was >0.1%/year and if the diagnosis age was <70 years, while active surveillance was preferred if surgical complication risk was >11%. Probabilistic sensitivity analysis demonstrated that at a willingness-to-pay of USD 100,000/QALY, immediate surgical treatment was the most cost-effective strategy in 64% of iterations. Conclusion: Immediate surgical treatment is a cost-effective strategy for initial management of small UIAs in patients <70 years of age. While more costly than MRA, surgical treatment increased QALY. The cost-effectiveness of immediate surgery is highly sensitive to diagnosis age, rupture rate, and surgical complication risk. Though there are a wide range of rupture rates and complications associated with treatment, this analysis supports the treatment of small, unruptured anterior circulation intracranial aneurysms in patients <70 years of age.

Risk Factors for Higher Volume of Hemorrhage in Ruptured Anterior Circulation Intracranial Aneurysms.

Purpose: To explore the influencing factors of volume hemorrhage in ruptured anterior circulation aneurysms, so as to identify the characteristics of anterior circulation aneurysms with high volume of hemorrhage, and to provide advice for clinical diagnosis and treatment for those aneurysms.Methods: We retrospectively reviewed 437 cases of ruptured anterior intracranial aneurysms in our center between the years 2012 and 2017. According to the inclusion criteria, a total of 100 qualified patients were screened out. We collected demographic characteristics, environmental exposure, and admission status of enrolled patients. In addition, morphological parameters and location of aneurysms were also included. The semiautomatic threshold method was used to measure the volume of hemorrhage. According to the results, the patients were divided into the group with high blood volume and low blood volume. Univariate and multivariate logistic regression analyses were used to discover the related factors affecting the bleeding volume.Results: In univariable analysis, pulse pressure (P = 0.014) showed a significant difference at the P < 0.05 test level. In terms of aneurysm morphology, the irregular shape (P < 0.001), calcification (P = 0.001), and flow angle (P = 0.006) showed significant statistical differences between the two groups at the P < 0.01 level (P < 0.01). Multivariate logistic regression analysis showed that irregular shape (OR = 5.370 P = 0.002 < 0.05), large flow angle (OR = 1.033 P = 0.016 < 0.05), and calcification (OR = 5.460 P = 0.003 < 0.05) were risk factors for volume of hemorrhage in ruptured anterior circulation aneurysms. The influence of hypertension history was at critical state (OR = 2.877 P = 0.051 > 005).Conclusions: According to our analysis results, intracranial anterior circulation aneurysms with irregular shapes, calcifications, and large flow angle are more dangerous. Aneurysms with these characteristics often have a large amount of hemorrhage, requiring timely treatment in clinical practice.

Feasibility and Safety of Radial-First Approach with a Radial-Specific Neurointerventional Guiding Sheath for Intracranial Aneurysm Coiling in the Anterior Circulation

In cardiac intervention, the transradial approach (TRA) is increasingly used as the first-line approach owing to numerous advantages over the transfemoral approach. Neurointerventional TRA, especially in intracranial interventions, is predominantly restricted to an alternative approach, as transradial carotid cannulation using a conventional transfemoral system can be technically challenging for patients with unfavorable acute takeoff of the target common carotid artery. This study evaluated the feasibility and safety of first-line TRA with a radial-specific neurointerventional guiding sheath for a large series of consecutive intracranial anterior circulation aneurysm embolizations. We retrospectively analyzed our institutional database of first-line TRA for consecutive coil embolizations of anterior circulation aneurysms conducted between June 2018 and March 2020. A radial-specific 6-F Simmons guiding sheath (0.088-inch inner diameter) was engaged into the target common carotid artery, and subsequently a triaxial or quadraxial system was created for the embolization procedure. We assessed procedural success and procedure-related or vascular access site complications. A total of 119 patients with intracranial anterior circulation aneurysms underwent 121 coil embolization procedures. Of these, 101 patients who underwent 103 (85.1%) embolization procedures treated with first-line TRA were included. After the triaxial or quadraxial system was constructed, the embolization procedure was successful for all 103 cases without catheter kinking, system instability, or complications. A transradial 0.088-inch triaxial or quadraxial system provided sufficient stability and kink resistance for intracranial aneurysm embolization. This method is feasible, highly successful, and safe for intracranial anterior circulation aneurysm embolization.

Flow diversion versus parent artery occlusion with bypass in the treatment of complex intracranial aneurysms: Immediate and short-term outcomes of the randomized trial

ObjectiveWe performed prospective randomized comparison of clinical and surgical outcomes of flow diversion versus PVO and bypass in patients with complex anterior circulation aneurysms. Patients and methodsOpen, prospective, randomized, parallel group, multicenter study of complex intracranial aneurysms treatment was conducted. Patients with complex intracranial aneurysms of anterior circulation with neck is more than 4 mm wide, dome/neck ratio is equal or less than 2:1, which is suitable for flow diversion and occlusion with bypass were included in the study. A total of 111 potential participants were enrolled since March 2015. Additional propensity score matching was performed with 40 patients in each group selected for analysis. Results39 out of 40 patients (97.5%) from matched FD group reached good clinical outcome.In the matched bypass group acceptable outcome was achieved in 32 (80%) out of 40 patients (difference between groups p = 0.029). The morbidity and mortality rates were 15% and 5%, respectively. Difference in the rates of favorable outcomes, compared by χ2 met statistical significance (p = 0.014). The rate of complete aneurysm occlusion at 6 months was 42.5% in the FD group and 95% in surgical group (p < 0.0001). The rate of complete occlusion at 12 months was 65% in the FD group and 97.5% in surgical group. The difference between groups was still significant (p = 0.001). There were no significant differences between groups by occurrence of ischemic (p = 0.108) and hemorrhagic (p = 0.615) complications. ConclusionThe study demonstrated superior clinical outcomes for endovascular flow diversion in comparison with bypass surgery in treatment of complex aneurysms. Though, both techniques grant similar percentage of major neurologic complications and comparable cure rate for cranial neuropathy. Nevertheless, flow diversion is associated with significantly lower early obliteration rate, thus possesses patient for risks of prolonged dual antiplatelet regimen and delayed rupture. Hence, it’s important to stratify patient by the natural risk of aneurysm rupture prior to treatment selection.

Asymptomatic Ischemic Risks in Microsurgical Clipping for Unruptured Intracranial Aneurysms in Anterior Circulation.

The ischemic risk in prophylactic treatments of unruptured intracranial aneurysms (UIAs) is a serious health concern. The aim of this study was to elucidate the incidence and characteristics of ischemic events in microsurgical clipping of anterior circulation UIAs. Ischemic events were prospectively evaluated before and after surgery between April 2011 and March 2017. The location, volume, minimum value of apparent diffusion coefficient in high-intensity spots (HIS) on 3-T magnetic resonance diffusion-weighted imaging (DWI), and radiographic outcomes were analyzed. The relationships between DWI positivity and patient demographics, surgical procedures, and intraoperative vessel features were assessed. Overall, 78 consecutive patients including 29 men and 49 women (median age, 62 years; range, 24-77 years) with 99 UIAs were analyzed. A total of 10 in 78 craniotomies (13%) detected HIS on DWI, which were all asymptomatic. Seventeen HIS were shown, 5 of which were located in the basal ganglia, 6 in the white matter, and 6 in the cortex. The volume and minimum value of apparent diffusion coefficient were 180.4 ± 31.2 mm3 and 0.56 ± 0.03× 10-3 mm2/second, respectively. Radiographic outcomes at follow-up showed that 71% of HIS on DWI led to irreversible brain ischemia. The maximum diameter of aneurysms, atherosclerotic features of the aneurysm wall, and procedure-related factors were associated with DWI positivity. The asymptomatic ischemic risk associated with microsurgical clipping was not low and most lesions were irreversible. Although the mechanism could be various, the use of clips for atherosclerosis of the aneurysm and/or parental vessels requires much attention.

Optimal Guiding Catheter Length for Endovascular Coiling of Intracranial Aneurysms in Anterior Circulation in Era of Flourishing Distal Access System.

PurposeTo determine the minimum required guiding catheter length for embolization of various intracranial aneurysms in anterior circulation and to analyze the effect of various patient factors on the required catheter length and potential interaction with its stability.Materials and MethodsFrom December 2016 to March 2017, 90 patients with 93 anterior circulation aneurysms were enrolled. Three types of guiding catheters (Envoy, Envoy DA, and Envoy DA XB; Codman Neurovascular, Raynham, MA, USA) were used. We measured the in-the-body length of the catheter and checked the catheter tip location in the carotid artery. We analyzed factors affecting the in-the-body length and stability of the guiding catheter system.ResultsThe average (±standard deviation) in-the-body length of the catheter was 84.2±5.9 cm. The length was significantly longer in men (89.1±5.6 vs. 82.1±4.6 cm, P<0.001), patients older than 65 years (87.7±7.8 vs. 82.7±4.2 cm, P<0.001), patients with a more tortuous arch (arch type 2 and 3) (87.5±7.4 vs. 82.7±4.4 cm, P<0.001), and patients with a distal aneurysm location (distal group) (86.2±5.0 vs. 82.7±6.1 cm, P=0.004). A shift in the tip location was noted in 19 patients (20.4%); there was no significant different among the 3 catheters (P=0.942).ConclusionThe minimum required length of a guiding catheter was 84 cm on average for elective anterior-circulation aneurysm embolization. The length increased in men older than 65 years with a more tortuous arch. We could reach a higher position with distal access catheters with little difference in the stability once we reached the target location.

Non-Contrast-Enhanced Silent Scan MR Angiography of Intracranial Anterior Circulation Aneurysms Treated with a Low-Profile Visualized Intraluminal Support Device.

The Low-Profile Visualized Intraluminal Support Device comprises a small-cell nitinol structure and a single-wire braided stent that provides greater metal coverage than previously reported intracranial stents, as well as assumed strong susceptibility artifacts. This study aimed to assess the benefits of non-contrast-enhanced MRA by using a Silent Scan (Silent MRA) for intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents. Thirty-one aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents were assessed by using Silent MRA, 3D TOF-MRA, and x-ray DSA. The quality of MRA visualization of the reconstructed artery was graded on a 4-point scale from 1 (not visible) to 4 (excellent). Aneurysm occlusion status was evaluated by using a 2-grade scale (total occlusion/remnant [neck or aneurysm]). Weighted κ statistics were used to evaluate interobserver and intermodality agreement. The mean scores ± SDs for Silent MRA and 3D TOF-MRA were 3.16 ± 0.79 and 1.48 ± 0.67 (P < .05), respectively, with substantial interobserver agreement (κ = 0.66). The aneurysm occlusion rates of the 2-grade scale (total occlusion/remnant [neck or aneurysm]) were 69%/31% for DSA, 65%/35% for Silent MRA, and 92%/8% for 3D TOF-MRA, respectively. The intermodality agreements were 0.88 and 0.30 for DSA/Silent MRA and DSA/3D TOF-MRA, respectively. Silent MRA seems to be useful for visualizing intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents.

Abstract WP85: Flow-diverter Embolization for Tandem Intracranial Aneurysms: A Single Center Experience

Introduction: Flow diverter embolization is a novel method to treat intracranial aneurysms. The device has been shown to reduce procedure time and radiation exposure along with excellent long-term occlusion rates for single lesions. However, the effect of flow diversion on multiple adjacent aneurysms has not been well studied. We present our single center experience with flow diverter treatment of tandem aneurysms. Methods: We retrospectively collected clinical, imaging, procedural and follow up data on patients in whom flow diverters were used to treat intracranial anterior circulation aneurysms between 2011 and 2016. We included patients who had 2 or more tandem aneurysms of the internal carotid artery segment and where flow diverter was intended to treat all the aneurysms either as primary or secondary method. Results: We identified 21 patients with 52 aneurysms that met inclusion criteria. All were females with median age of 57 (Interquartile range [IQR] 51 - 69). Seventeen patients had 2 adjacent aneurysms, while 4 patients had 3 contiguous aneurysms. Of these, only one patient was treated acutely for ruptured aneurysm. The median largest aneurysm diameter was 3.1mm (IQR 2.5 - 4.8) with most common locations being cavernous and ophthalmic aneurysms. In 19 patients (90.5%) only a single flow diverter stent was used; only one patient required concurrent coiling. One patient (4.8%) suffered a post procedural mild stroke but improved rapidly. There were no other procedural complications. Follow up data in 13 patients (61.9%) with a median follow up of 8 months (IQR 6 - 13) demonstrated that 20 out of 28 aneurysms showed complete occlusion (71.4%). None of the patients at follow up required re-treatment, and there were no delayed/late aneurysm ruptures. Conclusion: Flow diverter is a feasible, efficacious and safe treatment option in patients with multiple tandem aneurysms, in a single session with good early outcomes. Long term follow up data and large cohort studies are required.

Assessment of Pre- and Post-Operative Cerebral Perfusion in Anterior Circulation Intracranial Aneurysm Clipping Patients at Hospital Sungai Buloh Using CT Perfusion Scan and Correlations to Fisher, Navarro and WFNS Scores.

Intracranial aneurysms may rupture and are typically associated with high morbidity and mortality, commonly due to vasospasm after rupture. Once the aneurysm ruptures, the patient's cerebral blood flow may be disturbed during the acute phase, affecting cerebral circulation and thus cerebral perfusion prior to the onset of vasospasm. Fisher and Navarro scores are used to predict vasospasm, while World Federation of Neurosurgical Societies (WFNS) scores are used to predict patient outcomes. Several score modifications are available to obtain higher sensitivity and specificity for the prediction of vasospasm development, but these scores are still unsuccessful. Alternatively, cerebral CT perfusion scan (CTP) is a non-invasive method for measuring cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in regions of interests (ROI) to obtain the cerebral perfusion status as well as detecting vasospasm. A total of 30 patients' data with clipped anterior circulation intracranial aneurysms admitted to the hospital between 1 January 2013 and 30 June 2014, were collected from the hospital's electronic database. The data collected included patients' admissions demographic profiles, Fisher, Navarro and WFNS scores; and their immediate pre- and post-operative CTP parameters. This study found a significant increase in post-operative MTT (pre- and post-operative MTT) were 9.75 (SD = 1.31) and 10.44 (SD = 1.56) respectively, (P < 0.001)) as well as a significant reduction in post-operative CBF (pre- and post-operative mean CBF were 195.29 (SD = 24.92) and 179.49 (SD = 31.17) respectively (P < 0.001)). There were no significant differences in CBV. There were no significant correlations between the pre- and post-operative CTP parameters and Fisher, Navarro or WFNS scores. Despite the interest in using Fisher, Navarro and WFNS scores to predict vasospasm and patient outcomes for ruptured intracranial aneurysms, this study found no significant correlations between these scores in either pre- or post-operative CTP parameters. These results explain the disagreement in the field regarding the multiple proposed grading systems for vasospasm prediction. CTP measures more than just anatomical structures; therefore, it is more sensitive towards minor changes in cerebral perfusion that would not be detected by WFNS, Fisher or Navarro scores.

Endovascular Treatment of Intracranial Anterior Circulation Aneurysms with Flow Diverters: A Single Centre Experience with mid and long-term results.

We report our experience with flow diverter devices in the treatment of intracranial aneurysms arising from anterior circulation with mid and long-term follow-up. 78 aneurysms in 61 patients (range 25-81 years, 13 male, 48 female) were treated with flow diverter devices. 40 (51,3%) aneurysms were treated with pipeline embolization device (PED), 24 (30,8%) aneurysms were treated with SILK stent, 12(15,4%) aneurysms were treated with flow redirection endoluminal device (FRED) and two aneurysms were treated with P64 Flow Modulation Device (P64). Angiographic follow-up data at six month and one yea were recorded and the occlusion degrees of aneurysms were evaluated according to the scale which was formed by Kamran et al. At six month follow-up, complete occlusion (grade 4) rate was 60,8% and at one year increased to 74,3%. Statistical analysis revealed significant difference (p=0,002) between six month and one year follow-up results but there was no significant association (p=0,531, p=1,000) between aneurysm occlusion rate and aneurysm diameter. Two patient (3,2%) died due to hemorrhagic complication. Endovascular treatment of intracranial anterior circulation aneurysms with flow diverters is a safe and effective treatment option. A high rate of stable occlusion is achieved at long term follow-up.