Treatment of pediatric intracranial aneurysms: institutional case series and systematic literature review

INTRODUCTION

Pediatric intracranial aneurysms (IAs) are rare and have distinct clinical profiles compared to adult IAs. They differ in location, size, morphology, presentation, and treatment strategies. We present our experience with pediatric IAs over an 18-year period using surgical and endovascular treatments and review the literature to identify commonalities in epidemiology, treatment, and outcomes.

METHODS

We identified all patients < 20 years old who underwent treatment for IAs at our institution between 2005 and 2020. Medical records and imaging were examined for demographic, clinical, and operative data. A systematic review was performed to identify studies reporting primary outcomes of surgical and endovascular treatment of pediatric IAs. Demographic information, aneurysm characteristics, treatment strategies, and outcomes were collected.

RESULTS

Thirty-three patients underwent treatment for 37 aneurysms over 18 years. The mean age was 11.4 years, ranging from one month to 19 years. There were 21 males (63.6%) and 12 females (36.4%), yielding a male: female ratio of 1.75:1. Twenty-six (70.3%) aneurysms arose from the anterior circulation and 11 (29.7%) arose from the posterior circulation. Aneurysmal rupture occurred in 19 (57.5%) patients, of which 8 (24.2%) were categorized as Hunt-Hess grades IV or V. Aneurysm recurrence or rerupture occurred in five (15.2%) patients, and 5 patients (15.2%) died due to sequelae of their aneurysms. Twenty-one patients (63.6%) had a good outcome (modified Rankin Scale score 0-2) on last follow up. The systematic literature review yielded 48 studies which included 1,482 total aneurysms (611 with endovascular treatment; 656 treated surgically; 215 treated conservatively). Mean aneurysm recurrence rates in the literature were 12.7% and 3.9% for endovascular and surgical treatment, respectively.

CONCLUSIONS

Our study provides data on the natural history and longitudinal outcomes for children treated for IAs at a single institution, in addition to our treatment strategies for various aneurysmal morphologies. Despite the high proportion of patients presenting with rupture, good functional outcomes can be achieved for most patients.

Impact of an AI software on the diagnostic performance and reading time for the detection of cerebral aneurysms on time of flight MR-angiography

PURPOSE

To evaluate the impact of an AI-based software trained to detect cerebral aneurysms on TOF-MRA on the diagnostic performance and reading times across readers with varying experience levels.

METHODS

One hundred eighty-six MRI studies were reviewed by six readers to detect cerebral aneurysms. Initially, readings were assisted by the CNN-based software mdbrain. After 6 weeks, a second reading was conducted without software assistance. The results were compared to the consensus reading of two neuroradiological specialists and sensitivity (lesion and patient level), specificity (patient level), and false positives per case were calculated for the group of all readers, for the subgroup of physicians, and for each individual reader. Also, reading times for each reader were measured.

RESULTS

The dataset contained 54 aneurysms. The readers had no experience (three medical students), 2 years experience (resident in neuroradiology), 6 years experience (radiologist), and 12 years (neuroradiologist). Significant improvements of overall specificity and the overall number of false positives per case were observed in the reading with AI support. For the physicians, we found significant improvements of sensitivity on lesion and patient level and false positives per case. Four readers experienced reduced reading times with the software, while two encountered increased times.

CONCLUSION

In the reading with the AI-based software, we observed significant improvements in terms of specificity and false positives per case for the group of all readers and significant improvements of sensitivity and false positives per case for the physicians. Further studies are needed to investigate the effects of the AI-based software in a prospective setting.

Bridging the gap: robotic applications in cerebral aneurysms neurointerventions - a systematic review

Cerebral aneurysm is a life-threatening condition, which requires high precision during the neurosurgical procedures. Increasing progress of evaluating modern devices in medicine have led to common usage of robotic systems in many fields, including cranial aneurysm operations. However, currently no systematic review describes up-to date knowledge of this topic. Following PRISMA guidelines, we have independently screened and extracted works from seven databases. Only studies fulfilling inclusion criteria were presented in this study. Device used, operation time, complications, aneurysm type and patient demographics were extracted from each work. We identified a total of 995 articles from databases. We have found six original works and one supplementary article eligible for this synthesis. Majority of works (4/6) have implemented CorPath GRX in cerebral aneurysm procedures. The procedures involved diverse aneurysm locations, utilizing flow diverters, stents, or coiling. One study described implementation of robot-assist on 117 patients and compared results to randomized clinical trials. One work with a small patient cohort described use of the magnetically-controlled microguidewire in the coiling procedures, without any complications. Additionally, one case-series study described use of a robotic arm for managing intraoperative aneurysm rupture. Currently, robotical devices for cerebral aneurysm treatment mainly lack jailing and haptic feedback feature. Further development of these devices will certainly be beneficial for operators and patients, allowing for more precise and remote surgeries.

Prediction of obliteration of unruptured cerebral aneurysm by residual aneurysm volume after flow diverter stent treatment

Introduction There is no methodology to predict aneurysm occlusion using residual volume after flow diverter stent treatment. We retrospectively examined whether residual aneurysm volume at 6 months postoperatively can predict the degree of aneurysm obliteration at 1 year after flow diverter stent treatment. Materials and Methods This single institution study included 101 consecutive patients who underwent flow diverter stent treatment for unruptured cerebral aneurysm. Based on pre-treatment aneurysm volume, the percentage residual volume was calculated 6 months postoperatively. The volume of the aneurysm was determined using the volume calculation function of the cerebral angiography equipment. 1 year postoperatively, patients were classified into two groups: the good obliteration group (GG; O'KellyMarotta [OKM] grading scale: C and D) and the poor obliteration group (PG; OKM: A and B). Statistical analysis was performed to determine if there was a difference in residual aneurysm volume percentage at 6 months postoperatively between the two groups. Results A total of 20 patients were studied: 6 in the GG and 14 in the PG. Mean residual aneurysm volume at 6 months postoperatively in the GG was 33.1% (±34.7), while that in the PG was 80.6% (±24.8) (P=0.018). A residual aneurysm volume of ≥35.2% at 6 months postoperatively was significantly associated with poor aneurysm obliteration at 1 year postoperatively (AUC=0.88, P=0.008). Conclusions Residual aneurysm volume percentage at 6 months after flow diverter stent treatment might be able to predict the likelihood of aneurysm occlusion at 1 year postoperatively.

An assessment of how the anterior cerebral artery anatomy impacts ACoA aneurysm formation based on CFD analysis

OBJECTIVE

The aim of this study was to identify independent anatomic, morphologic and hemodynamic features of the ACoA (anterior communicating artery) complex that serve as risk factors for the occurrence of ACoA aneurysms.

METHODS

Fifteen consecutive patients with 15 ACoA aneurysms were included. Computational fluid dynamics (CFD) simulations based on patient-specific models were carried out using 3D time-of-flight magnetic resonance angiography (3D-TOF-MRA) images. A reverse reconstruction technique was used to generate a pre-aneurysm vessel anatomy. Geometric parameters and hemodynamic changes were compared and evaluated.

RESULTS

The overall prevalence of symmetric, dysplastic, and absent A1 segments were 53.3%, 26.7%, and 20%. The mean wall shear stress (WSS) of the absent group (AG) was significantly higher than that of the symmetric group (SG) and dysplastic group (DG). The absolute mean A1 artery flow rate (410.2 ± 88 versus 439.4 ± 101 mL/min; p = .45) of the aneurysm side was similar between the SG and DG but significantly higher in the AG (528.1 ± 77 mL/min; p < .05). The A1-A2 angles of the aneurysm side showed no significant differences among the 3 groups (p = .32). However, the mean A1-A2 angle on the aneurysm side was smaller than the contralateral A1-A2 angle (101.9 ± 9.1˚ versus 120.3 ± 7.7˚; p <.05). A regression analysis demonstrated that high WSS was significantly associated with a large A1-A2 ratio (R2=0.52; p <.05).

CONCLUSIONS

ACoA aneurysms are a high-WSS pathology. Severe flow impingement and the anatomic vasculature structures play a role in triggering the occurrence of ACoA aneurysms.

Determination of Significant Three-Dimensional Hemodynamic Features for Postembolization Recanalization in Cerebral Aneurysms Through Explainable Artificial Intelligence

BACKGROUND

Recanalization poses challenges after coil embolization in cerebral aneurysms. Establishing predictive models for postembolization recanalization is important for clinical decision making. However, conventional statistical and machine learning (ML) models may overlook critical parameters during the initial selection process.

METHODS

In this study, we automated the identification of significant hemodynamic parameters using a PointNet-based deep neural network (DNN), leveraging their three-dimensional spatial features. Further feature analysis was conducted using saliency mapping, an explainable artificial intelligence (XAI) technique. The study encompassed the analysis of velocity, pressure, and wall shear stress in both precoiling and postcoiling models derived from computational fluid dynamics simulations for 58 aneurysms.

RESULTS

Velocity was identified as the most pivotal parameter, supported by the lowest P value from statistical analysis and the highest area under the receiver operating characteristic curves/precision-recall curves values from the DNN model. Moreover, visual XAI analysis showed that robust injection flow zones, with notable impingement points in precoiling models, as well as pronounced interplay between flow dynamics and the coiling plane, were important three-dimensional features in identifying the recanalized aneurysms.

CONCLUSIONS

The combination of DNN and XAI was found to be an accurate and explainable approach not only at predicting postembolization recanalization but also at discovering unknown features in the future.

Virtual and analytical self-expandable braided stent treatment models

The Flow Diverter is a self-expandable braided stent that has helped improve the effectiveness of cerebral aneurysm treatment during the last decade. The Flow Diverter's efficiency heavily relies on proper decision-making during the pre-operative phase, which is currently based on static measurements that fail to account for vessel or tissue deformation. In the context of providing realistic measurements, a biomechanical computational method is designed to aid physicians in predicting patient-specific treatment outcomes. The method integrates virtual and analytical treatment models, validated against experimental mechanical tests, and two patient treatment outcomes. In the case of both patients, deployed stent length was one of the validated result parameters, which displayed an error inferior to 1.5% for the virtual and analytical models. These results indicated both models' accuracy. However, the analytical model provided more accurate results with a 0.3% error while requiring a lower computational cost for length prediction. This computational method can offer designing and testing platforms for predicting possible intervention-related complications, patient-specific medical device designs, and pre-operative planning to automate interventional procedures.

Anterior inferior cerebellar artery aneurysm with proximal parent artery stenosis: A case report

Hemodynamic factors are associated with the progression of cerebral aneurysms. We report a 78-year-old woman with an anterior inferior cerebellar artery aneurysm and proximal stenosis of the anterior inferior cerebellar and basilar arteries. The aneurysm exhibited growth on annual follow-up imaging. Aneurysmal rupture occurred 4 years after diagnosis. Coil embolization resulted in aneurysm occlusion with parent artery preservation. Aneurysms adjacent to a more proximal region of severe stenosis in the parent vessel should be considered at high risk for growth or rupture. Such aneurysms require careful monitoring. Particular attention should be paid to posterior circulation aneurysms that occur at anatomically vulnerable sites.

The Effect of Preoperative Three Dimensional Modeling and Simulation on Outcome of Intracranial Aneursym Surgery

OBJECTIVE

Three-dimensional (3D) printing in vascular surgery is trending and is useful for the visualisation of intracranial aneurysms for both surgeons and trainees. The 3D models give the surgeon time to practice before hand and plan the surgery accordingly. The aim of this study was to examine the effect of preoperative planning with 3D printing models of aneurysms in terms of surgical time and patient outcomes.

METHODS

Forty patients were prospectively enrolled in this study and divided into two groups : groups I and II. In group I, only the angiograms were studied before surgery. Solid 3D modelling was performed only for group II before the operation and was studied accordingly. All surgeries were performed by the same senior vascular neurosurgeon. Demographic data, surgical data, both preoperative and postoperative modified Rankin scale (mRS) scores, and Glasgow outcome scores (GOS) were evaluated.

RESULTS

The average time of surgery was shorter in group II, and the difference was statistically significant between the two groups (p<0.001). However, no major differences were found for the GOS, hospitalisation time, or mRS.

CONCLUSION

This study is the first prospective study of the utility of 3D aneurysm models. We show that 3D models are useful in surgery preparation. In the near future, these models will be used widely to educate trainees and pre-plan surgical options for senior surgeons.

A Systematic Review and Meta-Analysis of 3-Dimensional Morphometric Parameters for Cerebral Aneurysms

BACKGROUND

Imaging modalities with increased spatial resolution have allowed for more precise quantification of cerebral aneurysm shape in 3-dimensional (3D) space. We conducted a systematic review and meta-analysis to assess the correlation of individual 3D morphometric measures with cerebral aneurysm rupture status.

METHODS

Two independent reviewers performed a PRISMA (preferred reporting items of systematic reviews and meta-analysis)-guided literature search to identify articles reporting the association between 3D morphometric measures of intracranial aneurysms and rupture status.

RESULTS

A total of 15,122 articles were identified. After screening, 39 studies were included. We identified 17 3D morphometric measures, with 11 eligible for the meta-analysis. The meta-analysis showed a significant association with rupture status for the following measures: nonsphericity index (standardized mean difference [SMD], 0.66; 95% confidence interval [CI], 0.53-0.79; P < 0.0001; I2 = 55.2%), undulation index (SMD, 0.55; 95% CI, 0.26-0.85; P = 0.0017; I2 = 68.1%), ellipticity index (SMD, 0.53; 95% CI, 0.29-0.77; P = 0.0005; I2 = 70.8%), volume (SMD, 0.18; 95% CI, 0.02-0.35; P = 0.0320; I2 = 82.3%), volume/ostium ratio (SMD, 0.43; 95% CI, 0.16-0.71; P = 0.0075; I2 = 90.4%), elongation (SMD, -0.94; 95% CI, -1.12 to -0.76; P = 0.0005; I2 = 0%), flatness (SMD, -0.87; 95% CI, -1.04 to -0.71; P = 0.0005; I2 = 0%), and sphericity (SMD, -0.62; 95% CI, -1.06 to -0.17; P = 0.0215; I2 = 67.9%). A significant risk of publication bias was estimated for the ellipticity index (P = 0.0360) and volume (P = 0.0030).

CONCLUSIONS

Based on the results of a meta-analysis containing 39 studies, the nonsphericity index, undulation index, elongation, flatness, and sphericity demonstrated the most consistent correlation with rupture status.

Internal carotid artery-persistent primitive anterior choroidal artery aneurysms: report of two cases and literature review

PURPOSE

Persistent primitive anterior choroidal artery (PPAChA) is a rare vascular anomaly. The clinical course of internal carotid artery (ICA)-PPAChA aneurysms has not been well described.

CASE REPORTS

We report two patients with an ICA-PPChA aneurysm and summarize previously reported cases.

RESULTS

Including our two, a total of 10 patients with an ICA-PPAChA aneurysm have been reported. Data were not described for one. Among the remaining nine, five patients (56%) experienced aneurysmal rupture. Five patients underwent surgical clipping and four underwent endovascular coiling. The procedure was completed in all but one patient who had a tiny branch artery adherent to the aneurysm; this patient was converted from clipping to aneurysm coating with a cotton sheet. Among the other eight patients, one who underwent coiling experienced an internal capsule infarction. The remaining seven had a satisfactory postoperative course; however, an asymptomatic occlusion of the PPAChA at its origin was noted on postoperative angiography in one.

CONCLUSION

PPChA is associated with a high incidence of aneurysm formation and rupture. During treatment of ICA-PPAChA aneurysms, obstruction of the PPAChA and any surrounding perforating arteries should be avoided to prevent ischemic stroke.

Three-Dimensional (3D) Microcatheter Shaping Using Touch Screen Devices for Cerebral Aneurysm Coil Embolization

OBJECTIVE

In cerebral aneurysm coil embolization, proper microcatheter shaping is crucial to reduce complications and achieve sufficient embolization. Shaping a microcatheter in 3 dimensions (3D) is often required but can be challenging. We assessed the usefulness of a novel shaping on screen (SOS) method that displays real-size 3D rotational angiography (RA) images on a touch screen device during cerebral aneurysm embolization to facilitate 3D microcatheter shaping.

METHODS

In this study, 18 patients with cerebral aneurysm treated with this technique were included. Real-size 3D-RA images obtained during the embolization procedure were displayed on the touch screen device, which allowed for real-time manipulation. The shape of the microcatheter was adjusted to conform to the curvature of the vessel by swiping the touch screen device and bending the mandrel accordingly. We assessed the clinical and angiographic results, along with the accuracy and stability of the microcatheter.

RESULTS

No procedure-related complications were observed. The mean packing density was 41% ± 12%. In all but 1 case, microcatheters were inserted into the aneurysms without guidewire assistance. After coiling, all microcatheter forms were stable.

CONCLUSIONS

Three-dimensional (3D) microcatheter shaping using touch screen devices during cerebral aneurysm coil embolization may be simple and safe and can achieve high packing density of aneurysms.

Effect of the pipeline embolization device placement on branching vessels in anterior circulation: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Pipeline embolization device (PED) is widely used in intracranial aneurysms, and the scope of applications for the PED, which is frequently used to treat cerebral aneurysms, is also growing. It has some effect on branching vessels as a result of its inherent properties. The effects of PED on the complications rate and branching vessels blockage have not yet been thoroughly investigated.

OBJECTIVE

We conducted a systematic review searching reports from multiple databases on PED use for intracranial aneurysms, and analyzed the influence of PED on the occlusion rate of different branching vessels, and the influence of the amount of PED on the occlusion rate of branching vessels by meta-analysis.

METHODS

We searched the literature using PUBMED, Web of Science, and OVID databases until August 2023. Inclusion criteria were that the study used only PED, included at least 10 patients, and recorded branching vessels occlusion rates, mortality, and neurological complications.

RESULTS

Nine studies were analyzed consisting of 706 patients with 986 side branches. The results of the meta-analysis showed that application of more than one PED did not significantly elevate the rate of branching vessels occlusion compared to application of one PED (OR = 0.70; 95% CI: 0.34 to 1.43; P = 0.33). In the comparison of branching vessels occlusion rates in the anterior circulation, the anterior cerebral artery (ACA) had a significantly higher occlusion rate compared to the ophthalmic artery (OphA) (OR = 6.54; 95% CI: 3.05 to 14.01; P < 0.01), ACA also had a higher occlusion rate compared to the anterior choroidal artery (AchA) (OR = 15.44; 95% CI: 4.11 to 57.94 P < 0.01), ACA versus posterior communicating artery (PcomA) occlusion rate difference was not statistically significant (OR = 2.58; 95% CI: 0.63 to 12.82; P = 0.17), OphA versus AchA occlusion rate difference was not statistically significant (OR = 2.56; 95% CI: 0.89 to 7.38; P = 0.08), and the occlusion rate was significantly higher for PcomA compared to AchA (OR = 7.22; 95% CI: 2.49 to 20.95; P < 0.01) and lower for OphA compared to PcomA (OR = 0.33; 95% CI: 0.19 to 0.55; P < 0.01).

CONCLUSION

The meta-analysis shows that use of multiple PEDs did not significantly increase the occlusion rate of branching vessels, and the larger the diameter of branching vessels covered by PED, the higher the occlusion rate of branching vessels. However, the incidence of complications is low after branching vessels occlusion in anterior circulation, which is related to the collateral circulation compensation of the branching vessels.

Comparison of endovascular interventional embolization and microsurgical clipping for ruptured cerebral aneurysms: impact on patient outcomes

OBJECTIVE

To compare the therapeutic efficacy of endovascular interventional embolization and microsurgical clipping in patients with ruptured cerebral aneurysms and investigate their subsequent influence on inflammatory indices, neurological function, prognosis, and recovery.

METHODS

The two groups were compared in terms of surgery duration, hospital stay, Hunt-Hess classification, and inflammatory indices before and after the surgery, as well as National Institutes of Health Stroke Scale (NIHSS), Baethel Index (BI), and one-year prognosis of patients affected.

RESULTS

The surgery duration and hospital stay of the intervention group were (116.27 ± 12.32) min and (19.82 ± 2.26) d, respectively, and those of the clipping group was (173.87 ± 10.39) min and (24.11 ± 2.33) d, respectively (both p < 0.05). Neither the intervention nor the microscopic approach had a significant impact on the severity of the patients' conditions in terms of Hunt-Hess classification (p > 0.05). In the intervention group, CRP was changed to (5.31 ± 1.22) mg/L and PCT decreased to (1.17 ± 0.39) μg/L after the surgery, while the corresponding values in clipping group were (9.78 ± 2.35) mg/L and (2.75 ± 0.81) μg/L (p > 0.05). After surgery, both groups' NIHSS scores declined dramatically, with the intervention group scoring lower than the microscopy group (6.81 ± 1.22 vs 8.72 ± 1.27) (p < 0.05).

CONCLUSION

The findings of this study support the potential advantages of endovascular interventional embolization (coiling) over microsurgical clipping for the management of ruptured cerebral aneurysms. These advantages include shorter surgical duration, reduced hospital stay, lower inflammatory response, improved neurological and functional outcomes, and better long-term prognosis.

Persistent intracranial hyper-inflammation in ruptured cerebral aneurysm after COVID-19: case report and review of the literature

BACKGROUND

The systemic manifestations of coronavirus disease 2019 (COVID-19) include hyperinflammatory reactions in various organs. Recent studies showed evidence for the frequent involvement of central nervous system in affected patients; however, little is known about clinical features of cerebrovascular diseases in childhood-onset COVID-19.

CASE PRESENTATION

A 10-year-old boy recovered from SARS-CoV-2 infection without complication. On 14 days after infection, he presented with loss of consciousness. A head computed tomography detected a ruptured cerebral aneurysm at the left posterior cerebral artery accompanying subarachnoid hemorrhage (SAH). Immediate surgical intervention did not rescue the patient, resulting in the demise 7 days after admission. Serological and genetic tests excluded the diagnosis of vasculitis and connective tissue disorders. Retrospective analysis showed markedly higher levels of interleukin (IL)-1β, IL-6 and IL-8 in the cerebrospinal fluid than the serum sample concurrently obtained. A review of literature indicated that adult patients with COVID-19 have a risk for the later development of SAH during the convalescent phase of COVID-19.

CONCLUSIONS

SAH is a severe complication of COVID-19 in children and adults who have asymptomatic cerebrovascular aneurysms. The markedly high levels of cytokines detected in the cerebrospinal fluid suggested that intracranial hyperinflammatory condition might be one of the possible mechanisms involved in the rupture of a preexisting cerebrovascular aneurysms.

Effect of Intrathecal Urokinase Infusion on Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Vasospasm following an aneurysmal subarachnoid hemorrhage (SAH) causes serious neurological complications, despite surgical clipping of the aneurysm. Intrathecal urokinase (UK) infusion has been shown to effectively prevent symptomatic vasospasm in patients who have undergone endovascular obliteration of the ruptured aneurysms.

OBJECTIVE

To investigate whether intrathecal UK infusion can prevent symptomatic vasospasm in patients undergoing surgical or endovascular treatment.

METHODS

A total of 90 patients with severe aneurysmal SAH were enrolled and assigned to a surgical neck clipping (n = 56) or an endovascular coil embolization (n = 34) groups. After treatment, UK infusion from the lumbar drain was repeated in 32 patients in the surgical neck clipping group (group B) and all in the endovascular coil embolization group (group C) until complete resolution of the SAH was observed on computed tomography. The remaining 24 of the surgical neck clipping group, without UK infusion, were assigned to group A.

RESULTS

Symptomatic vasospasm occurred in 7 (29.2%) patients in group A, 2 (6.3%) in group B, and none in group C (group A vs. group B [P = 0.02]; group B vs. group C [P = 0.14]). Excellent clinical outcomes (modified Rankin score, 0 or 1) were observed in 37.5%, 59.4%, and 76.5% of patients in group A, B, and C, respectively (group A vs. group B [P = 0.11]).

CONCLUSION

Clearance of SAH via intrathecal UK infusion significantly reduced symptomatic vasospasm in patients in both UK groups, resulting in better clinical outcomes.

Transient Locked-in Syndrome after Aneurysmal Subarachnoid Bleeding due to Spasm Hypoxemia?

How to cite this article: Finsterer J. Transient Locked-in Syndrome after Aneurysmal Subarachnoid Bleeding due to Spasm Hypoxemia? Indian J Crit Care Med 2024;28(1):86.

Fractals and Chaos in the Hemodynamics of Intracranial Aneurysms

Computing the emerging flow in blood vessel sections by means of computational fluid dynamics is an often applied practice in hemodynamics research. One particular area for such investigations is related to the cerebral aneurysms, since their formation, pathogenesis, and the risk of a potential rupture may be flow-related. We present a study on the behavior of small advected particles in cerebral vessel sections in the presence of aneurysmal malformations. These malformations cause strong flow disturbances driving the system toward chaotic behavior. Within these flows, the particle trajectories can form a fractal structure, the properties of which are measurable by quantitative techniques. The measurable quantities are well established chaotic properties, such as the Lyapunov exponent, escape rate, and information dimension. Based on these findings, we propose that chaotic flow within blood vessels in the vicinity of the aneurysm might be relevant for the pathogenesis and development of this malformation.

Management of a ruptured posterior inferior cerebellar artery (PICA) aneurysm with end-to-end in situ bypass: Case report

Dissecting posterior inferior cerebellar artery (PICA) aneurysms are uncommon lesions. Their anatomy and the location of the dissection are variable, however, they usually occurs at the origin of the PICA. Dissecting PICA aneurysms generally have non-vascular morphology involving an entire segment of the artery and cannot be cut. Nevertheless, the detection of these vascular lesions has increased latterly, so it is necessary to recognize it and take the appropriate management modalities for these injuries. In this report, we describe a case of a 73-year-old male patient, who presented a history of severe headache, associated with neck stiffness, nausea, vomiting, dizziness, hypoactivity, mental confusion, and walking difficulty. Radiographic investigation with brain computed tomography (CT) showed mild bleeding in a pre-medullary and pre-pontine cistern, and cerebral angiogram showed a dissecting PICA aneurysm. Despite being a challenging treatment, microsurgery management was the chosen modality. It was performed an end-to-end anastomosis between the p2/p3 segments, showing to be effective with good clinical and radiographic outcomes. We discussed an unusual case, reviewing the current literature on clinical presentations, the angiographic characteristics of the dissecting aneurysms of PICA, and evaluating the clinical and angiographic results of patients undergoing microsurgical treatment.

Impact of ventriculo-cisternal irrigation on prevention of delayed cerebral infarction in aneurysmal subarachnoid hemorrhage: a single-center retrospective study and literature review

OBJECTIVE

The aim of this study was to evaluate the effectiveness of ventriculo-cisternal irrigation (VCI) in preventing vasospasms and delayed cerebral infarction (DCI) by washing out subarachnoid clots earlier after aneurysm surgery.

METHODS

We retrospectively identified 340 subarachnoid hemorrhage (SAH) patients with ruptured intracranial aneurysms treated with postoperative VCI at our institution between December 2010 and January 2020. As VCI therapy, a ventricular drain/cisternal drain was placed during aneurysm surgery, and lactated Ringer's solution was used for irrigation until day 4 of SAH, followed by intracranial pressure control at 5-10 cmH2O until day 14.

RESULTS

The median age was 65 years (interquartile range 52-75), with 236 female patients (69%). The World Federation of Neurosurgical Societies grade distribution was as follows: grade I or II, 175 patients (51%); grade III or IV, 84 (25%); and grade V, 81 (24%). With VCI management in all patients, total vasospasm occurred in 162 patients (48%), although the DCI incidence was low (23 patients [6.8%]). Major drainage-related complications were observed in five patients (1.5%). Early surgery, performed on SAH day 0 or 1, was identified as a preventive factor against DCI occurrence (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.07-0.67; P = 0.008), while additional surgery (4.76, 1.62-13.98; P = 0.005) and dyslipidemia (3.27, 1.24-8.63; P = 0.017) were associated with DCI occurrence.

CONCLUSION

Managing vasospasms with VCI after SAH is considered a safe and effective method to prevent DCI. Early surgery after SAH may be associated with a decreased risk of DCI with VCI therapy.

Early Outcomes of the Pipeline Vantage Flow Diverter : A Multicentre Study

PURPOSE

The recently introduced Pipeline Vantage Embolization Device with Shield Technology is the fourth generation of Pipeline flow diverter devices. Due to the relatively high rate of intraprocedural technical complications, modifications were subsequently made to the device after a limited release of the device in 2020. This study aimed to evaluate the safety and efficacy of the modified version of this device.

METHODS

This was a multicentre retrospective series. The primary efficacy endpoint was aneurysm occlusion in the absence of retreatment. The primary safety endpoint was any neurological morbidity or death. Ruptured and unruptured aneurysms were included in the study.

RESULTS

A total of 52 procedures were performed for 60 target aneurysms. Treatment was performed on 5 patients with ruptured aneurysms. The technical success rate was 98%. The mean clinical follow-up time was 5.5 months. In patients presenting with unruptured aneurysms there were no deaths, 3 (6.4%) major complications and 7 (13%) minor complications. In the five patients presenting with subarachnoid haemorrhage there were 2 (40%) major complications with 1 (20%) of these resulting in death, and 1 (20%) minor complication. Of the patients 29 (56%) had undergone 6‑monthly postprocedural angiographic imaging with a mean time of 6.6 months demonstrating that 83% of patients had achieved adequate occlusion (RROC1/2) of the aneurysm.

CONCLUSIONS

In this non-industry-sponsored study, the occlusion rates and safety outcomes were similar to those seen in previously published studies with flow diverter devices and earlier generation Pipeline devices. Modifications to the device appear to have improved ease of deployment.

Hemodynamic differences of posterior communicating artery aneurysms between adult and fetal types of posterior cerebral artery

BACKGROUND

The recanalization of posterior communicating artery (PCoA) aneurysms after endovascular treatment has been analyzed by various factors. However, the differences between adult and fetal types of posterior cerebral artery (PCA) have not been fully investigated. The main aim of this study was to investigate hemodynamic differences of PCoA aneurysms between adult and fetal types using computational fluid dynamics (CFD).

METHODS

Fifty-five PCoA aneurysms were evaluated by 3D CT angiography and divided into unruptured aneurysms with adult-type or fetal-type PCAs (19 cases, UA group; 9 cases, UF group) and ruptured aneurysms with adult-type or fetal-type PCAs (17 cases, RA group; 10 cases, RF group). These native aneurysms were analyzed by CFD regarding morphological and hemodynamic characteristics. To evaluate simulated endovascular treatment of aneurysms, CFD was performed using porous media modeling.

RESULTS

Morphologically, the RA group had significantly smaller parent artery diameter (2.91 mm vs. 3.49 mm, p=0.005) and higher size ratio (2.54 vs. 1.78, p=0.023) than the RF group. CFD revealed that the UA group had significantly lower oscillatory shear index (OSI) (0.0032 vs. 0.0078, p=0.004) than the UF group and that the RA group had lower WSS (3.09 vs. 11.10, p=0.001) and higher OSI (0.014 vs. 0.006, p=0.031) than the RF group, while the RF group presented significantly higher intra-aneurysmal flow velocity (0.19 m/s vs. 0.061 m/s, p=0.002) than the RA group. Porous media modeling of simulated treatment revealed higher residual flow volume in the fetal-type groups.

CONCLUSIONS

These results suggested that PCoA aneurysms with fetal-type PCAs had different morphological features and hemodynamic characteristics compared with those with adult-type PCAs, leading to high risks of recanalization.

Proximal Internal Carotid Artery Occlusion and Extracranial-Intracranial Bypass for Treatment of Fusiform and Giant Internal Carotid Artery Aneurysms

OBJECTIVE

To discuss the treatment of intracranial fusiform and giant internal carotid artery (ICA) aneurysms via revascularization based on our institutional experience.

METHODS

An institutional review board-approved retrospective analysis was performed of patients with unruptured fusiform and giant intracranial ICA aneurysms treated from November 1991 to May 2020. All patients were evaluated for extracranial-intracranial (EC-IC) bypass and ICA occlusion.

RESULTS

Thirty-eight patients were identified. Initially, patients failing preoperative balloon test occlusion were treated with superficial temporal artery (STA)-middle cerebral artery (MCA) bypass and concurrent proximal ICA ligation. We then treated them with STA-MCA bypass, followed by staged balloon test occlusion, and, if they passed, endovascular ICA coil occlusion. We treat all surgical medically uncomplicated patients with double-barrel STA-MCA bypass and concurrent proximal ICA ligation. The mean length of follow-up was 99 months. Symptom stability or improvement was noted in 85% of patients. Bypass graft patency was 92.1%, and all surviving patients had patent bypasses at their last angiogram. Aneurysm occlusion was complete in 90.9% of patients completing proximal ICA ligation. Three patients experienced ischemic complications and 4 patients experienced hemorrhagic complications.

CONCLUSIONS

Not all fusiform intracranial ICA aneurysms require intervention, except when life-threatening rupture risk is high or symptomatic management is necessary to preserve function and quality of life. EC-IC bypass can augment the safety of proximal ICA occlusion. The rate of complete aneurysm occlusion with this treatment is 90.9%, and long-term bypass graft-related complications are rare. Perioperative stroke is a major risk, and continued evolution of treatment is required.

Mass Effect After Flow Diversion for Unruptured Large and Giant Cavernous or Paraclinoid Internal Carotid Artery Aneurysm

OBJECTIVE

The mass effect associated with large or giant intracranial aneurysms is difficult for traditional endovascular treatment. This study investigated whether flow diverters can relieve the aneurysmal mass effect caused by aneurysmal compression symptoms.

METHODS

Fifty-five patients with unruptured large and giant intracranial aneurysms treated by a flow diverter at our institution from January 2014 to February 2022 were retrospectively evaluated.

RESULTS

In this study, 53 patients were included. Initially, 27 patients (51.9%), including 10 with compressive optic neuropathy, 12 with third nerve palsy, 2 with facial hyperesthesia, and 11 with sixth nerve palsy, were symptomatic. The symptom duration was shorter in the improved group (n = 2.2 ± 4.0 vs. n = 3.1 ± 3.9, P = 0.49). Thrombus formation following the flow diversion procedure was typically observed on magnetic resonance imaging (MRI) performed immediately and was not significantly associated with symptomatic improvement (OR = 0.395; 95% CI (0.058-2.698), P = 0.343). However, symptomatic improvement was seen in most patients when the aneurysm size decreased on MRI. A reduction in the aneurysm size on the MRI at the 3-month follow-up was correlated with symptomatic improvement in the multivariate analysis (OR = 0.08, 95% CI (0.013-0.485), P < 0.05).

CONCLUSIONS

A flow diverter might help alleviate compression symptoms caused by large or giant intracranial aneurysms. Shrinkage of the aneurysm within 3 months postoperatively and a shorter duration of symptoms contribute to the favorable outcomes of mass effect. Ultimately, prompt treatment is crucial for improving symptomatic intracranial artery aneurysms.

Clinical Efficiency of an Artificial Intelligence-Based 3D-Angiography for Visualization of Cerebral Aneurysm: Comparison with the Conventional Method

PURPOSE

Artificial intelligence (AI)-based three-dimensional angiography (3D-A) was reported to demonstrate visualization of cerebral vasculature equivalent to that of three-dimensional digital subtraction angiography (3D-DSA). However, the applicability and efficacy of the AI-based 3D‑A algorithm have not yet been investigated for 3D-DSA micro imaging. In this study, we evaluated the usefulness of the AI-based 3D‑A in 3D-DSA micro imaging.

MATERIALS AND METHODS

The 3D-DSA micro datasets of 20 consecutive patients with cerebral aneurysm (CA) were reconstructed with 3D-DSA and 3D‑A. Three reviewers compared 3D-DSA and 3D‑A in terms of qualitative parameters (degrees of visualization of CA and the anterior choroidal artery [AChA]) and quantitative parameters (aneurysm diameter, neck diameter, parent vessel diameter, and visible length of AChA).

RESULTS

Qualitative evaluation of diagnostic potential revealed that visualization of CA and the proximal to middle parts of the AChA with 3D‑A was equal to that with conventional 3D-DSA; in contrast, visualization of the distal part of the AChA was lower with 3D‑A than with 3D-DSA. Further, regarding quantitative evaluation, the aneurysm diameter, neck diameter, and parent vessel diameter were comparable between 3D‑A and 3D-DSA; in contrast, the visible length of the AChA was lower with 3D‑A than with 3D-DSA.

CONCLUSIONS

The AI-based 3D‑A technique is feasible and evaluable visualization of cerebral vasculature with respect to quantitative and qualitative parameters in 3D-DSA micro imaging. However, the 3D‑A technique offers lower visualization of such as the distal portion of the AChA than 3D-DSA.

Towards Prediction of Blood Flow in Coiled Aneurysms Before Treatment: A Porous Media Approach

Modeling blood flow in aneurysms treated with coils could be used to understand the complete embolization of the aneurysm, through thrombus formation that fills the entire sac. Modeling of the endovascular coil mass as a porous medium is a technique that allows for study of aneurysm hemodynamics, efficiently for patient-specific treatment outcome predictions. Models in the literature use mean porosity of coils in the aneurysmal volume, proving inadequate for outcome prediction. However, models that consider heterogeneous porosity distribution have shown more accurate hemodynamics. We recently published the porous crown model, considering the heterogeneous coil mass distribution, validated on two patients. This study aims (i) to validate the porous crown model for a larger cohort (eight patients), and (ii) to propose a porous medium model translatable to clinical practice in treatment planning. We analyzed the porosity distribution of the endovascular coils deployed inside the cerebral aneurysm phantoms of eight patients using 3D x-ray synchrotron images. The permeability and inertial factor of the porous crown model are calculated using previously published methodology. We propose a new "bilinear" porous model, that uses the same hypothesis, but the permeability and inertial factor can be defined from just basic information available in the neuro-suite, i.e., the aneurysmal sac volume and the coil volume fraction targeted by the neurosurgeon. These two models are compared to the coil-resolved simulations, considered as the gold standard. The results show that both the porous crown model and the bilinear model produce similarly accurate hemodynamics in the aneurysm. The error in the standard (mean porosity) porous model is 66%, whereas the error of the bilinear model is 26%, compared to the coil-resolved. The bilinear model is promising as a means of treatment outcome prediction at time of intervention.

Impact of blood pressure and antihypertensive drug classes on intracranial aneurysm: a Mendelian randomization study

BACKGROUND

Blood pressure is a risk factor for intracranial aneurysms (IA). Nevertheless, whether various antihypertensive drug classes discriminate in reducing IA risk is unclear.

METHODS

Genome-wide association study summary statistics for systolic blood pressure (SBP), diastolic blood pressure (DBP), IA (non-ruptured), and IA [subarachnoid hemorrhage (SAH)] were downloaded. To proxy the effects of antihypertensive drugs, genetic variants associated with SBP adjacent to the coding regions of different antihypertensive drugs were selected. The inverse-variance-weighted (IVW) method was employed as the primary method for causal estimation. In addition, three additional MR methods and sensitivity tests were utilized to assess the reliability.

RESULTS

Elevated blood pressure significantly increases the risk of IA: (i) SBP-IA (non-ruptured): odds ratio (OR) = 1.046, 95 % confidence interval (CI): 1.032-1.061, P = 1.05E-10; (ii) SBP-IA (SAH): OR = 1.040, 95 % CI: 1.030-1.050, P = 2.56E-15; (iii) DBP-IA (non-ruptured): OR = 1.082, 95 % CI: 1.056-1.110, P = 3.15E-10; (iv) DBP-IA (SAH): OR = 1.066, 95 % CI: 1.047-1.085, P = 1.25E-12. In addition, among calcium channel blockers (CCBs), beta-blockers (BBs), and thiazide diuretics (TDs), only SBP mediated by TDs target genes significantly increased the risk of IA (non-rupture) (OR = 1.164, 95 % CI: 1.060-1.279, P = 0.001) and IA (SAH) (OR = 1.136, 95 % CI: 1.063-1.214, P = 1.58E-04), while SBP mediated by target genes of BBs or CCBs did not causally associate with IA.

CONCLUSION

Elevated blood pressure significantly increases IA risk, while TDs may be a promising antihypertensive medication for reducing IA risk. Further research with larger cohorts is essential for validation.

Immunoliposomes for detection of rupture-prone intracranial aneurysms

BACKGROUND

It is estimated that significant (3.2%) of population carries intracranial aneurysm (IA). An increasing number of imaging studies have caused that the chance of finding an incidental aneurysm is becoming more common. Since IA rupture causes subarachnoidal hemorrhage (SAH) and have significant mortality and morbidity prophylactic treatment should be considered when IA is detected. The benefit and risk of treatment of IA is based on epidemiological estimate which takes account patient and aneurysm characteristics. However we know that aneurysm rupture is biological process where inflammation of aneurysm wall is actively leading to degeneration of aneurysm wall and finally weakens it until it bursts. Until now, there have not been imaging method to detect inflammatory process of aneurysm wall METHODS: We created targeting immunoliposome for use in the imaging of aneurysm. Immunoliposome comprises antibodies against at least one vascular inflammatory marker associated with aneurysm inflammation and a label and/or a contrast agent.

RESULTS

Histological analysis of IAs where immunoliposome comprises antibodies against vascular inflammation with a label shows promising results for selectively detecting aneurysms inflammation. In magnetic resonance imaging (MRI) we were able to detect immunoliposomes carrying gadolinium.

CONCLUSION

Our work opens a new avenue for using contrast labeled immunoliposomes for detecting rupture-prone aneurysms. Immunoliposomes can cary gadolinium and selectively bind to inflammatory section of aneurysm that can be detected with MRI. Further research is needed to develop immunoliposomes to be used with MRI in humans to target treatment to those patients who benefit from it the most.

Length of Survival, Outcome, and Potential Predictors in Poor-Grade Aneurysmal Subarachnoid Hemorrhage Patients Treated with Microsurgical Clipping

BACKGROUND

Poor-grade aneurysmal subarachnoid hemorrhage (aSAH) has been associated with severe morbidity and high mortality. It has been demonstrated that early intervention is of paramount importance. The aim of our study is to evaluate the functional outcome and the overall survival of early microsurgically treated patients.

MATERIAL AND METHODS

Poor-grade aSAH patients admitted at our institution over fifteen years (January 2008 - December 2022) were included in our retrospective study. All participants underwent brain Computed Tomography Angiography (CTA). Fisher scale was used to assess the severity of hemorrhage. All our study participants underwent microsurgical clipping, and their functional outcome was assessed with the Glasgow Outcome Scale (GOS). We used logistic regression analysis to identify any parameters associated with a favorable outcome at 12 months. Cox proportional hazard analysis was also performed, identifying factors affecting the length of survival.

RESULTS

Our study included 39 patients with a mean age of 54 years. Thirty of our participants (76.9%) were Hunt and Hess grade V, while the vast majority (94.9%) were Fisher grade 4. The observed six-month mortality rate was 48.6%. The mean follow-up time was 18.6 months. The functional outcome at six months was favorable in 6 patients (16.2%), increased to 23.5% at 12 months. Our data analysis showed that the age, as well as the employment of temporary clipping during surgery, affected the overall outcome.

CONCLUSION

Management of poor-grade aSAH patients has been dramatically changed. Microsurgical clipping provides promising results in carefully selected younger patients.

Paraclinoid aneurysms clipping through an extradural sphenoid ridge keyhole approach

BACKGROUND

Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping.

METHOD

A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case.

CONCLUSION

Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.

Preoperative Rehearsal Sketch for Cerebral Aneurysm Clipping Improves the Accuracy and the Safety of the Surgical Procedure

OBJECTIVE

With advances in endovascular therapy, the number of cerebral aneurysm clippings has been decreasing. However, some patients are indicated for clipping surgeries. In such circumstances, preoperative simulation is important for the safety and educational aspects of the operation. Herein, we introduce a simulation method using the preoperative rehearsal sketch and report its applicability.

METHODS

We compared the preoperative rehearsal sketch with the surgical view for all patients who underwent cerebral aneurysm clipping by neurosurgeons below the seventh grade between April 2019 and September 2022 in our facility. The aneurysm, running of parent and branched arteries, perforators, veins, and clip working were evaluated by senior doctors and scored as follows: correct, 2; partially correct, 1; incorrect, 0; and total score, 12. We retrospectively evaluated the relationship between these scores and postoperative perforator infarctions and, in addition, compared that between simulated and not simulated cases.

RESULTS

In the simulated cases, the total scores did not correlate with perforator infarctions, but assessments of the aneurysm, perforators, and clip working affected the total score (P = 0.039, 0.014, and 0.049, respectively). Moreover, perforator infarctions were significantly less in the simulated cases (6.3% vs. 38.5%; P = 0.03).

CONCLUSIONS

Precise interpretations of preoperative images and considerations of three-dimensional images are imperative to perform safe and accurate surgeries using preoperative simulation. Although perforators are not always detected preoperatively, it is possible to presume in the surgical view using anatomic knowledge. Therefore, drawing the preoperative rehearsal sketch improves the safety of surgical procedure.

In-stent stenosis after stenting the PulseRider for a middle cerebral artery aneurysm: A case report

PulseRider is a self-expanding stent implant used to treat wide-necked aneurysms. As this device has a lower metal mass than conventional stents, it is expected to have a lower rate of ischemic complications and a shorter period with antiplatelet drugs. We experienced in-stent stenosis after endovascular treatment with the PulseRider for a middle cerebral artery aneurysm. A 40-year-old woman with an unruptured aneurysm in the middle cerebral artery bifurcation underwent coil embolization using a PulseRider. The periprocedural course was not problematic, and postoperative angiography showed contrast filling in the aneurysm. The patient was discharged from our hospital on postembolization day 3. However, follow-up angiography after 6 months showed in-stent stenosis. Fortunately, no ischemic complications occurred after treatment. Although the PulseRider is characterized by a low metal mass, it should be noted that this device has some metal markers that can induce in-stent stenosis.

Left Transradial Access Using a Radial-Specific Neurointerventional Guiding Sheath for Coil Embolization of Anterior Circulation Aneurysm Associated With the Aberrant Right Subclavian Artery: Technical Note and Literature Review

BACKGROUND

Aberrant right subclavian artery (ARSA) is a rare condition, but the most common anomaly of the aortic arch. Although neurointerventions via transradial access (TRA) are becoming increasingly popular worldwide, transradial carotid cannulation has been extremely challenging in patients with an ARSA. Herein, we present a case of ARSA-associated anterior communicating artery (ACoA) aneurysm that was successfully treated with a radial-specific 6F Simmons guiding sheath via left TRA. We also review the relevant literature.

METHODS

A 68-year-old-woman who was diagnosed as having an ARSA-associated ACoA aneurysm underwent simple coiling via left TRA. After the 6F Simmons guiding sheath was engaged into the right common carotid artery using the pull-back-technique, transradial quadraxial system (6F Simmons guiding sheath/6F intermediate catheter/3.2F intermediate catheter/coil-delivery microcatheter) was implemented.

RESULTS

Simple coiling of the aneurysm was successfully achieved without catheter kinking or system instability. The postprocedural course was uneventful. A follow-up magnetic resonance angiography showed no evidence of recanalization 1 years 9 months after the procedure.

CONCLUSIONS

Transradial anterior circulation intervention has been rarely used for patients with an ARSA due to unfavorable catheter trajectory. Left TRA using the 6F Simmons guiding sheath is a useful treatment option to address anterior circulation interventions for patients with an ARSA. Preoperative diagnosis of ARSA is necessary for the application of our method.

ICGA combined with EP monitoring in microclipping of cerebral aneurysms

Cerebral aneurysm is one of the common cerebrovascular diseases in neurosurgery, and rupture of cerebral aneurysm is the most important cause of spontaneous subarachnoid hemorrhage. How to precisely clip the aneurysm has been a topic worth discussing, so the authors explore the value of ICGA combined with electrophysiological monitoring in the microclipping of cerebral aneurysms. Using the method of retrospective analysis of cases, 661 patients with cerebral aneurysms admitted to the Department of Neurosurgery, Zhongnan Hospital of Wuhan University, from 2021.8 to 2022.10 were studied, 390 patients with aneurysm clipping were included, and patients with Hunt-Hess classification ≥ 4 were excluded, and whether to use ICGA combined with EP in microclipping of the ruptured and unruptured aneurysm in pterional approach was investigated at the time of discharge, respectively. The MRS and total hospital days were compared to investigate the value of ICGA combined with EP in the microclipping of cerebral aneurysms. All 390 patients enrolled in the group had successful aneurysm clipping, 178 patients were screened for ruptured aneurysm pterional approach and 120 patients for unruptured aneurysm pterional approach access; the MRS at discharge was significantly lower in the ICGA combined with EP group than in the no-EP group for ruptured aneurysm pterional approach microclipping (p < 0.001), and the mean number of days in hospital was significantly lower (p < 0.01). Patients in the ICGA combined with EP group in microclipping of unruptured aneurysms with pterional approach also had significantly lower MRS at discharge compared with patients in the ICGA alone group (p < 0.001), with no statistically significant difference in the mean number of days in hospital (p = 0.09). In open cerebral aneurysm microclipping, ICGA combined with EP monitoring for both ruptured and unruptured aneurysms can effectively reduce the false-negative rate of ICGA, significantly reduce the incidence of postoperative neurological deficits, and shorten the total hospital stay to some extent. ICGA combined with EP monitoring may be an effective means to reduce the rate of false clipping of the penetrating vessels and to avoid stenosis or occlusion of the aneurysm-carrying artery and is worth promoting in microclipping of cerebral aneurysms except for Hunt-Hess ≥ 4.

Comparative study on the clinical outcomes and prognosis of endovascular embolization and craniotomy clipping for the treatment of cerebral aneurysms

Objective

To investigate the safety and outcomes of endovascular embolization and craniotomy clipping in the treatment of cerebral aneurysms.

Methods

We collected the clinical data of 106 patients with cerebral aneurysm who underwent surgical treatment (endovascular embolization, Group-A, n=55; craniotomy clipping, Group-B, n=51) in the First People's Hospital of Yichang from January 2020 to May 2021. We compared surgical treatment indexes, treatment costs, neurological function before and after the treatment, incidence of postoperative complications and the prognosis after one-year follow-up between the two groups.

Results

Endovascular embolization (Group-A) was associated with a shorter mean operation time and hospital stay, a lower mean intraoperative bleeding amount, and a higher mean treatment cost than craniotomy clipping (Group-B) (P<0.05). Compared with the pre-operative neurological function scores, the scores of both groups decreased after the surgery, and the mean post-operative score of Group-A was significantly lower than that of Group-B (P<0.05). Compared with Group-B , patients in Group-A had a lower overall complication rate (P < 0.05. Higher proportion of patients in Group-A had a good prognosis (P < 0.05).

Conclusion

Endovascular embolization for the treatment of cerebral aneurysms is safe as it can shorten the operation time and hospital stay, reduce the incidence of neurological injury and complications, and have a favorable prognosis. However, the treatment is more expensive. Endovascular embolization can be selected for the treatment of cerebral aneurysms when economic conditions allow it.

Endovascular Treatment and Peri-interventional Management of Ruptured Cerebrovascular Lesions During Pregnancy : Case Series and Case-based Systematic Review

PURPOSE

Hemorrhagic stroke, particularly occurring from ruptured cerebrovascular malformations, is responsible for 5-12% of all maternal deaths during pregnancy and the puerperium. Whether endovascular treatment is feasible and safe for both the mother and the fetus, is still a matter of debate. The main objective of this case series and systematic review was to share our multi-institutional experience and to assess the feasibility and safety of endovascular treatment during pregnancy, as well as the corresponding maternal and fetal outcomes based on currently available evidence.

METHODS

We report a case series of 12 pregnant women presenting with hemorrhagic stroke from ruptured cerebrovascular arteriovenous malformations or aneurysms who underwent endovascular treatment prior to delivery. A systematic literature review of pregnant patients with endovascular treated cerebrovascular malformations, published between 1995 and 2022, was performed. Clinical patient information, detailed treatment strategies, maternal and fetal outcomes as well as information on the delivery were collected and assessed.

RESULTS

In most patients the course was uneventful and an excellent outcome without significant neurological deficits (mRS ≤ 1) was achieved. Furthermore, the maternal outcome was not worse compared to the general population who underwent endovascular treatment of ruptured vascular brain lesions. Also, in most cases a healthy fetus was born.

CONCLUSION

Endovascular treatment of ruptured cerebrovascular malformations during pregnancy is safe and feasible regarding both aspects, the maternal and fetal outcomes. Still, a stronger knowledge base is needed to correctly approach future cases of intracranial hemorrhage in the pregnant population.

Numerical Study of a Thrombus Migration Risk in Aneurysm After Coil Embolization in Patient Cases: FSI Modelling

PURPOSE

There are still many challenges for modelling a thrombus migration process in aneurysms. The main novelty of the present research lies in the modelling of aneurysm clot migration process in a realistic cerebral aneurysm, and the analysis of forces suffered by clots inside an aneurysm, through transient FSI simulations.

METHODS

The blood flow has been modelled using a Womersley velocity profile, and following the Carreau viscosity model. Hyperelastic Ogden model has been used for clot and isotropic linear elastic model for the artery walls. The FSI coupled model was implemented in ANSYS® software. The hemodynamic forces suffered by the clot have been quantified using eight different clot sizes and positions inside a real aneurysm.

RESULTS

The obtained results have shown that it is almost impossible for clots adjacent to aneurysm walls, to leave the aneurysm. Nevertheless, in clots positioned in the centre of the aneurysm, there is a real risk of clot migration. The risk of migration of a typical post-coiling intervention clot in an aneurysm, in contact with the wall and occupying a significant percentage of its volume is very low in the case studied, even in the presence of abnormally intense events, associated with sneezes or impacts.

CONCLUSIONS

The proposed methodology allows evaluating the clot migration risk, vital for evaluating the progress after endovascular interventions, it is a step forward in the personalized medicine, patient follow-up, and helping the medical team deciding the optimal treatment.

Factors influencing early obliteration during flow diverter treatment of cerebral aneurysms: Establishment of an early obliteration inhibition score

OBJECTIVE

This retrospective study aimed to investigate factors associated with inhibition of early aneurysm obliteration after flow diverter (FD) treatment. We also created the early obliteration inhibition (EOI) score for pre-operative evaluation.

METHODS

We examined 110 cerebral aneurysms in 104 patients who underwent FD treatment. The following parameters were investigated: age, sex, symptoms, aneurysm location and type, maximum aneurysm diameter, parent vessel diameter, neck diameter, and dome-neck ratio. We also noted aneurysm location relative to the curvature of the parent artery and any branches arising from the aneurysm dome. Procedural factors such as FD diameter and length, number of FDs placed, type of FD, and use of adjunctive coiling were also investigated. Aneurysm obliteration was evaluated using digital subtraction angiography 3 months after the procedure. Adequate obliteration was defined as grade C or D on the O'Kelly-Marotta scale.

RESULTS

The following factors inhibited early obliteration: 1) extradural location, 2) saccular aneurysm, 3) aneurysm neck located at the outer convexity of the parent artery, and 4) arterial branch arising from the aneurysm dome. Odds ratios were used to create an EOI score. Receiver operating characteristic curve analysis showed that the optimal cut-off EOI score for adequate obliteration was 1.5 (area under the curve, 0.81; 95% confidence interval, 0.73-0.9; sensitivity, 0.9; specificity, 0.57).

CONCLUSION

The EOI score, which is based on factors that inhibit early obliteration, may predict early treatment outcomes of FD placement.

Hemodynamic Management in the Prevention and Treatment of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage

One of the most serious complications after subarachnoid hemorrhage (SAH) is delayed cerebral ischemia, the cause of which is multifactorial. Delayed cerebral ischemia considerably worsens neurological outcome and increases the risk of death. The targets of hemodynamic management of SAH have widely changed over the past 30 years. Hypovolemia and hypotension were favored prior to the era of early aneurysmal surgery but were subsequently replaced by the use of hypervolemia and hypertension. More recently, the concept of goal-directed therapy targeting euvolemia, with or without hypertension, is gaining preference. Despite the evolving concepts and the vast literature, fundamental questions related to hemodynamic optimization and its effects on cerebral perfusion and patient outcomes remain unanswered. In this review, we explain the rationale underlying the approaches to hemodynamic management and provide guidance on contemporary strategies related to fluid administration and blood pressure and cardiac output manipulation in the management of SAH.

Guidelines for the Neurocritical Care Management of Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

The neurointensive care management of patients with aneurysmal subarachnoid hemorrhage (aSAH) is one of the most critical components contributing to short-term and long-term patient outcomes. Previous recommendations for the medical management of aSAH comprehensively summarized the evidence based on consensus conference held in 2011. In this report, we provide updated recommendations based on appraisal of the literature using the Grading of Recommendations Assessment, Development, and Evaluation methodology.

METHODS

The Population/Intervention/Comparator/Outcome (PICO) questions relevant to the medical management of aSAH were prioritized by consensus from the panel members. The panel used a custom-designed survey instrument to prioritize clinically relevant outcomes specific to each PICO question. To be included, the study design qualifying criteria were as follows: prospective randomized controlled trials (RCTs), prospective or retrospective observational studies, case-control studies, case series with a sample larger than 20 patients, meta-analyses, restricted to human study participants. Panel members first screened titles and abstracts, and subsequently full text review of selected reports. Data were abstracted in duplicate from reports meeting inclusion criteria. Panelists used the Grading of Recommendations Assessment, Development, and Evaluation Risk of Bias tool for assessment of RCTs and the "Risk of Bias In Nonrandomized Studies - of Interventions" tool for assessment of observational studies. The summary of the evidence for each PICO was presented to the full panel, and then the panel voted on the recommendations.

RESULTS

The initial search retrieved 15,107 unique publications, and 74 were included for data abstraction. Several RCTs were conducted to test pharmacological interventions, and we found that the quality of evidence for nonpharmacological questions was consistently poor. Five PICO questions were supported by strong recommendations, one PICO question was supported by conditional recommendations, and six PICO questions did not have sufficient evidence to provide a recommendation.

CONCLUSIONS

These guidelines provide recommendations for or against interventions proven to be effective, ineffective, or harmful in the medical management of patients with aSAH based on a rigorous review of the available literature. They also serve to highlight gaps in knowledge that should guide future research priorities. Despite improvements in the outcomes of patients with aSAH over time, many important clinical questions remain unanswered.

Sequential rupture of two concomitant cerebral aneurysms

The diagnosis of multiple cerebral aneurysms in patients with a spontaneous aneurysmal subarachnoid haemorrhage is not uncommon. The incidence of rupture from a second aneurysm, whilst the patient is recovering from a first bleed is however extremely rare. We report a 21-year-old female with a WFNS grade 1 subarachnoid haemorrhage secondary to a ruptured 5mm right posterior communicating artery aneurysm which was secured with clipping. Sixteen days later, whilst an in-patient, she suffered a second SAH from a left anterior choroidal artery aneurysm which was subsequently coiled. Comparison of digital subtraction angiography showed an almost doubling of the aneurysm from 2.7x2 mm to 4.4x2.3 mm. We review the literature of previously reported simultaneous and sequential aneurysmal subarachnoid haemorrhage and add to the sparse literature on this rare phenomena.

Multiple intracranial enlarging dissecting aneurysms: a case report

BACKGROUND

Cases of multiple cerebral aneurysms are rare. In this case report, we describe a male patient with multiple, enlarging, and ruptured aneurysms. The two aneurysms were believed to be dissecting aneurysms.

CASE DESCRIPTION

A 47-year-old man presented with left limb paralysis. Magnetic resonance imaging revealed a cerebral infarction. Digital subtraction angiography (DSA) identified an aneurysm and occlusion in the right middle cerebral artery (MCA). The MCA aneurysm was remarkably enlarged on the eighth day after cerebral ischemia and was treated using endovascular techniques. Two weeks after the endovascular treatment, the patient experienced a severe headache and became comatose, and a subarachnoid re-hemorrhage was confirmed. The fourth DSA revealed an enlarging dissecting aneurysm in the posterior cerebral artery. The patient died without further treatment.

CONCLUSION

Some dissecting aneurysms rapidly enlarge and rupture.

Treatment of aneurysmal subarachnoid hemorrhage in subacute phase; retrospective comparison of treatment in sub- and hyper-acute phases

OBJECTIVE

As soon as possible treatment initiation for aneurysmal subarachnoid hemorrhage (aSAH) is recommended. However, some patients require treatment in "subacute" phase of aSAH, defined in this study as "more than one day after the onset". To establish an optimal treatment strategy for these patients, we retrospectively analyzed the clinical experience of treating ruptured aneurysm with either clipping or coiling in subacute phase.

METHODS

Patients treated for aSAH between 2015 and 2021were analyzed. Patients were divided into the hyperacute phase (within 24 h) and subacute phase (later than 24 h) groups. The subacute group was analyzed to determine whether the selected procedure and its timing affected postoperative course and clinical outcomes. In addition, we conducted a multivariate logistic regression analysis to determine the independent factors that affect clinical outcomes.

RESULTS

Of 215 patients, 31 were treated in the subacute phase. While cerebral vasospasm at initial imaging was more frequently observed in subacute group, there was no difference in incidence of postoperative vasospasms. Patients in subacute group seemed to have better clinical outcomes due to the milder severity at the time of treatment initiation. Risk of angiographic vasospasm seemed to be higher in patients treated with clipping than coiling, while no difference was seen in clinical outcomes. Multivariate logistic regression analysis showed that the timing and selected treatment did not significantly affect the clinical outcome or the occurrence of delayed vasospasm.

CONCLUSIONS

Treatment of aSAH in the subacute phase may also result in favorable clinical outcomes, similar to patients treated in the hyperacute phase with mild presentation. However, further investigations are required to establish the optimal treatment strategies for such patients.

Additional rescue stenting with Neuroform Atlas stents during stent-assisted coiling of saccular aneurysms

OBJECTIVE

Overlapping stenting is sometimes attempted during endovascular treatment of cerebral aneurysm as a rescue for coil herniation, stent mal-positioning, or in-stent thrombosis. We retrospectively evaluated the efficacy and safety of additional rescue stenting (ARS) in telescoping fashion with Neuroform Atlas stent (NAS) during stent-assisted coiling of saccular aneurysms.

METHODS

We collected clinical and radiological data of patients with saccular aneurysms treated with ARS using NASs between March 2018 and December 2021. Y or X-stent-assisted coiling technique was excluded.

RESULTS

Eighteen unruptured and 5 ruptured aneurysms in 23 patients were treated with ARS using NASs. Sizes of aneurysms ranged from 2.0 mm to 10.0 mm (mean: 5.0 mm). Immediate angiographic results were complete occlusion in 11 aneurysms, residual neck in 4 aneurysms, and residual sac in 8 aneurysms. Peri-operative morbidity was 4.3 %. Nineteen of 23 patients underwent follow-up conventional angiography (mean, 9.9 months). Results showed progressive occlusion in 10 (52.6 %) cases and asymptomatic in-stent stenosis in 3 (15.8 %) cases. At the end of the observation period (mean, 17.4 months), all 18 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS of 0), except one (mRS of 1). Of five patients with subarachnoid hemorrhage, four had a favorable outcome (mRS of 0-1), while the other one was dependent (mRS of 4).

CONCLUSION

In this report on 23 patients, ARS with NASs for treating saccular aneurysms showed good technical safety with favorable clinical and angiographic outcomes. However, delayed in-stent stenosis was not uncommon. Thus, regular imaging follow-up is required.

Delayed-onset adenosine deaminase deficiency with a novel synonymous mutation and a case series from China

BACKGROUND

Adenosine deaminase (ADA) is a key enzyme in the purine salvage pathway. Genetic defects of the ADA gene can cause a subtype of severe combined immunodeficiency. To date, few Chinese cases have been reported.

METHODS

We retrospectively reviewed the medical records of patients diagnosed with ADA deficiency in Beijing Children's Hospital and summarized the previously published ADA deficiency cases from China in the literature.

RESULTS

Nine patients were identified with two novel mutations (W272X and Q202 =). Early-onset infection, thymic abnormalities and failure to thrive were the most common manifestations of Chinese ADA-deficient patients. The ADA genotype has a major effect on the clinical phenotype. Notably, a novel synonymous mutation (c.606G>A, p.Q202=) was identified in a delayed-onset patient, which affected pre-mRNA splicing leading to a frameshift and premature truncation of the protein. Furthermore, the patient showed γδT cells expansion with an increased effect or phenotype, which may be associated with the delayed onset of disease. In addition, we reported cerebral aneurysm and intracranial artery stenosis for the first time in ADA deficiency. Five patients died with a median age of four months, while two patients received stem cell transplantation and are alive.

CONCLUSIONS

This study described the first case series of Chinese ADA-deficient patients. Early-onset infection, thymic abnormalities and failure to thrive were the most common manifestations in our patients. We identified a synonymous mutation that affected pre-mRNA splicing in the ADA gene, which had never been reported in ADA deficiency. Furthermore, we reported cerebral aneurysm in a delayed-onset patient for the first time. Further study is warranted to investigate the underlying mechanisms.

Endovascular and microsurgical management of blister aneurysms: a multi-centre review

Blister aneurysms (BA) are high-risk cerebrovascular lesions accounting for 1% of intracranial aneurysms. The defective vessel wall and broad-based neck make this clinical entity difficult to treat, with high rates of re-rupture and mortality in patients presenting with acute subarachnoid haemorrhage. Blister aneurysms pose substantial challenges for both endovascular and microsurgical management. The objective of this study is to evaluate endovascular and microsurgical outcomes in intracranial blister aneurysm management across two tertiary hospitals. A review of two tertiary hospitals with a systematic imaging database search for term of "blister" in modalities from January 2010 to October 2022 was conducted. Operation reports were screened for the 5-year period since cerebral angiogram reports transitioned to surgical database. Identified reports were screened and reviewed for confirmed diagnosis by consultant neuroradiologist. A total of 21 cases of blister aneurysms managed at respective facilities were included. Sixteen cases (76%) were managed endovascularly. Four cases (19%) were managed surgically-2 with primary clipping, and 2 wrap and clipping. One case was managed conservatively (5%). Clinical outcomes were discharge disposition, aneurysm exclusion and post-operative complications. BAs have challenging considerations with high mortality and morbidity. Endovascular treatment offers a less invasive modality with lower rates of intraoperative rupture and morbidity. Mortality rates and patients discharged home were comparable. Commencement of dual anti-platelet therapy was safe in patients with flow diversion stents despite sub-arachnoid blood volume. Management of blister aneurysms is complex. Endovascular treatment shows promise for acute management but careful collaborative consideration of antithrombotic regime and requirement for further surgery should be considered.

The Current Limitations and Advanced Analysis of Hemodynamic Study of Cerebral Aneurysms

Among the various perspectives on cerebrovascular diseases, hemodynamic analysis-which has recently garnered interest-is of great help in understanding cerebrovascular diseases. Computational fluid dynamics (CFD) analysis has been the primary hemodynamic analysis method, and studies on cerebral aneurysms have been actively conducted. However, owing to the intrinsic limitations of the analysis method, the role of wall shear stress (WSS), the most representative parameter, remains controversial. High WSS affects the formation of cerebral aneurysms; however, no consensus has been reached on the role of WSS in the growth and rupture of cerebral aneurysms. Therefore, this review aimed to briefly introduce the up-to-date results and limitations made through CFD analysis and to inform the need for a new hemodynamic analysis method.

Limitation of fenestrated clips during clipping of middle cerebral artery aneurysm: Technical note

Background

The middle cerebral artery (MCA) is a common site of cerebral aneurysms and 82.6% occur at the bifurcation. When surgery is selected as a therapeutic option, it intends to clip the neck completely because if some remnant occurs, there exists the possibility of regrowth and bleeding in the short- or long-term.

Methods

We analyzed one drawback of the fenestrated clips of Yasargil and Sugita types to occlude the neck totally at a specific point formed by the union of the fenestra with the blades, creating a triangular space where the aneurysm can protrude, giving place to a remnant that can lead to a future recurrence and rebleeding. We show two cases of ruptured MCA aneurysms in which a cross-clipping technique occluded a broad base and dysmorphic aneurysm using straight fenestrated clips.

Results

In both cases (one using a Yasargil clip and the other with a Sugita clip), a small remnant was visualized when fluorescein videoangiography (FL-VAG) was used. In both cases, the small remnant was clipped with a 3 mm straight miniclip.

Conclusion

We should be aware of this drawback when clipping aneurysms using fenestrated clips to ensure a complete obliteration of the aneurysm's neck.

Woven EndoBridge Device Migration and Microsnare Retrieval Strategy: Single Institutional Case Reports with Technical Video Demonstration

The Woven EndoBridge (WEB) (MicroVention/Terumo) device is a treatment option for wideneck bifurcation aneurysms. An uncommon adverse effect is WEB device migration. While certain bailout strategies for WEB recovery have been described, there is still a paucity of information on optimal strategies to maximize both short and long-term post-operative outcomes. We add 2 cases at our institution to the existing literature of WEBectomy in the setting of complicated intracranial aneurysm treatment. We discuss the long-term imaging outcomes with additional fluoroscopy video demonstrating our technique. Our findings reflect a clear benefit for the use of the Amplatz GooseneckTM microsnare (Medtronic) device as a means of WEB recovery, coupled with potential stent-assisted WEB embolization to remove the aneurysm from the parent circulation, while minimizing recurrence and thromboembolic complications.

Influence of stent-induced vessel deformation on hemodynamic feature of bloodstream inside ICA aneurysms

One of the effective treatment options for intracranial aneurysms is stent-assisted coiling. Though, previous works have demonstrated that stent usage would result in the deformation of the local vasculature. The effect of simple stent on the blood hemodynamics is still uncertain. In this work, hemodynamic features of the blood stream on four different ICA aneurysm with/without interventional are investigated. To estimate the relative impacts of vessel deformation, four distinctive ICA aneurysm is simulated by the one-way FSI technique. Four hemodynamic factors of aneurysm blood velocity, wall pressure and WSS are compared in the peak systolic stage to disclose the impact of defamation by the stent in two conditions. The stent usage would decrease almost all of the mentioned parameters, except for OSI. Stenting reduces neck inflow rate, while the effect of interventional was not consistent among the aneurysms. The deformation of an aneurysm has a strong influence on the hemodynamics of an aneurysm. This outcome is ignored by most of the preceding investigations, which focused on the pre-interventional state for studying the relationship between hemodynamics and stents. Present results show that the application of stent without coiling would improve most hemodynamic factors, especially when the deformation of the aneurysm is high enough.