Evaluation of the safety and efficacy of a Pipeline Flex embolization device for treatment of large, wide-necked intracranial aneurysms

Objective: To investigate the safety and effectiveness of the Pipeline Flex embolization device(PFED) in the treatment of large and wide-necked aneurysms in the internal carotid artery(ICA). Methods: The clinical data of 78 cases of large and wide-necked aneurysms in the ICA treated with this Pipeline Flex embolization device in Shanghai Hospital of the Second Military Medical University and Southern Hospital of Southern Medical University from February 2017 to June 2018 were retrospectively analyzed. Results: A total of 66 cases were treated with a Pipeline Flex embolization device, 10 with a pipeline flex embolization device, and 2 with a double tubride stent(10 patients were treated with a pipeline stent-assisted coil embolization in; and 2 patients were treated with two pipeline stents). The patients were followed up for 3 to 18 months(average, 9.25 months). Among them, 63 cases had complete occlusion of the neck of the aneurysm(Raymondl Class I; MRS score 0; 80.8%). Aneurysms recurred in 12 cases(Raymondl Class Ⅱ; MRS score 1; 15.4%). Delayed ischemic complications were observed in 1 case(MRS score >2; 0.13%). There was 1 case of poor release of stent and 1 case of stent stenosis(0.13%). Conclusion: The treatment of large, wide-necked aneurysms in the ICA with PFED has a high total occlusion rate and good prognosis was better than coil embolization, but the placement of PFED still has some neurological complications.

Interobserver reliability of computed tomography angiography in the assessment of ruptured intracranial aneurysm and impact on patient management

BACKGROUND Aneurysmal subarachnoid hemorrhage is an emergency that can lead to a high mortality rate and many severe complications.It is critical to make a rapid radiological evaluation of ruptured intracranial aneurysms(RIAs)to determine the appropriate surgical treatment.AIM To assess the reliability of computed tomography angiography(CTA)in assessing different features of ruptured intracranial aneurysm and its impact on patient management.METHODS The final cohort of this study consisted of 146 patients with RIAs(75 male and 71 female)who underwent cerebral CTA.Their age ranged from 25 to 80,and the mean age±SD was 57±8.95 years.Two readers were asked to assess different features related to the aneurysm and perianeurysmal environment.Inter-observer agreement was measured using kappa statistics.Imaging data extracted from non-contrast computed tomography and CTA were considered to categorize the study population into two groups according to the recommended therapeutic approach.RESULTS The inter-observer agreement of both reviewers was excellent for the detection of aneurysms(K=0.95,P=0.001),aneurysm location(K=0.98,P=0.001),and(K=0.98,P=0.001),morphology(K=0.92,P=0.001)and margins(K=0.95,P=0.001).There was an excellent interobserver agreement for the measurement of aneurysm size(K=0.89,P=0.001),neck(K=0.85,P=0.001),and dome-to-neck ratio(K=0.98,P=0.001).There was an excellent inter-observer agreement for the detection of other aneurysm-related features such as thrombosis(K=0.82,P=0.001),calcification(K=1.0,P=0.001),bony landmark(K=0.89,P=0.001)and branch incorporation(K=0.91,P=0.001)as well as perianeurysmal findings including vasospasm(K=0.91,P=0.001),perianeurysmal cyst(K=1.0,P=0.001)and associated vascular lesions(K=0.83,P=0.001).Based on imaging features,87 patients were recommended to have endovascular treatment,while surgery was recommended in 59 patients.71.2%of the study population underwent the recommended therapy.CONCLUSION CTA is a reproducible promising diagnostic imaging modality for detecting and characterizing cerebral aneurysms.

Posterior reversible encephalopathy syndrome following uneventful clipping of an unruptured intracranial aneurysm:A case report

BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is characterized mainly by occipital and parietal lobe involvement,which can be reversible within a few days.Herein,we report a rare case of PRES that developed after craniotomy for an unruptured intracranial aneurysm(UIA).CASE SUMMARY A 59-year-old man underwent clipping surgery for the treatment of UIA arising from the left middle cerebral artery.Clipping surgery was performed uneventfully,and he regained consciousness quickly immediately after the surgery.At the 4th hour after surgery,he developed a disorder of consciousness and aphasia.Magnetic resonance imaging revealed cortical and subcortical T2/FLAIR hyperintensities in the parietal,occipital,and frontal lobes ipsilaterally,without restricted diffusion,consistent with unilateral PRES.With conservative treatment,his symptoms and radiological findings almost completely disappeared within weeks.In our case,the important causative factor of PRES was suspected to be a sudden increase in cerebral perfusion pressure associated with temporary M1 occlusion.CONCLUSION Our unique case highlights that,to our knowledge,this is the second report of PRES developing after craniotomy for the treatment of UIA.Surgeons must keep PRES in mind as one of the causes of perioperative neurological abnormality following clipping of an UIA.

Wall shear stress in intracranial aneurysms and adjacent arteries

Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries.

Effectiveness of MRA on embolized intracranial aneurysms: a comparison of DSA, CE-MRA, and TOF-MRA

Purpose: The endovascular treatment of intracranial aneurysms was proven safe and effective compared to the alternative method of surgical clipping, despite the high recurrence rate. Follow-up of embolized intracranial aneurysms is mandatory for the early detection of recurrence and improved outcomes. DSA is used as the reference standard for this assessment. To determine the effectiveness of MRA in follow-up evaluations of intracranial aneurysms after embolization by comparing DSA, CE-MRA, and TOF-MRA. Materials and Methods: Sixty-eight consecutive patients undergoing DSA, TOF-MRA, and CE-MRA during an interval of <1 week were enrolled in this 6-month study. Images were evaluated for occlusion status, patency of the parent vessels, and artifacts. The modified Raymond-Roy occlusion classification and Aneurysm Embolization Grades were used to assess the occlusion status and initial DSA images for detection of recurrence in two filtered study phases with optimized selection criteria. Seventeen observers(phase I: 9, phase II: 8) independently interpreted the double-blinded images. Agreement was expressed with a Fleiss kappa value; p < 0.05 was considered significant. Results: This study included 68 patients with 77 aneurysms; 38(49.35%) were treated with coil alone and 39(50.65%) with stent-assisted coiling. In both phases, DSA was superior to TOF-MRA and CE-MRA using MRRC(Phase I: k = 0.567, p ≤ 0.001; k = 0.287, p ≤ 0.001; k = 0.117, p ≤ 0.001, respectively; Phase II: k = 0.503, p ≤ 0.001; k = 0.303, p ≤ 0.001; k = 0.115, p = 0.038, respectively). TOF-MRA was as effective as DSA(TOF: k = 0.335, p ≤ 0.001; DSA: k = 0.323, p ≤ 0.001) for recurrence detection. Conclusion: We suggest TOF-MRA as a first-line follow-up tool to detect aneurysm recurrence, and DSA to quantify the filling space to make a definite decision on re-embolization.

Nursing care of 22 patients with complex intracranial aneurysms treated with flow-diverting stents:A retrospective study

Objective:To summarize the nursing treatment of patients who underwent implantation of a blood flow diverter to treat complex intracranial aneurysms.Methods:Data from 22 patients with complex aneurysms,diagnosed at an interventional center for blood flow diverter implantation between February 2015 and February 2016,treated in the Henan Provincial People’s Hospital(Zhengzhou,China),were retrospectively analyzed.Nursing methods,including preoperative,intraoperative,and postoperative care,were analyzed.Results:All 22 patients underwent successful surgery,with no related complications or hospital mortality,and were cured in hospital.Conclusion:Interventional flow diverter therapy for patients with complex intracranial aneurysms is a new technology,and involves intensive care by nursing staff and appears to be a promising new treatment method.

Applications of multislice CT angiography in the surgical clipping and endovascular coiling of intracranial aneurysms

Prompt diagnosis and therapy of aneurysms are critical for patients with nontraumatic subarachnoid hemorrhage （SAH）.The aim of our study was to assess the clinical usefulness of multislice computed tomography angiography （CTA） in the surgical and endovascular treatment of intracranial aneurysms.A total of 195 cases with 206 intracranial aneurysms underwent CTA.Fifty （24%） aneurysms underwent surgical clipping while 156 （76%） aneurysms underwent endovascular coiling.In the five missed aneurysms at digital substraction angiography and the nine aneurysms with mass intracerebral hematomas,surgical treatment was successfully performed based on 16-slice CTA alone,and the other 36 aneurysms were clipped on the main basis of the CTA.The intraoperative findings correlated well with the CTA findings and all aneurysms were clipped successfully.Sixteen-slice CTA image information has been shown to determine the choice of aneurysm therapy and assist the surgical and endovascular treatment of intracranial aneurysms.

Efficacy of pipeline endovascular device and Willis stent graft in the treatment of traumatic pseudo intracranial aneurysms

Objective:To investigate the advantages and effects of pipeline embolization device(PED)or Willis stent,in treating traumatic pseudoaneurysms.Traumatic pseudo intracranial aneurysms(TPIA)can be caused by either direct trauma or iatrogenic injuries,usually caused by direct arterial wall injury or shear due to acceleration.We describe a series of patients with TPIA who received a PED or Willis stent.Materials and methods:Retrospective analysis was performed on nine patients with TPIA admitted to the southern hospital of Southern Medical University from December 2017 to June 2019,of whom four were treated with PED and five were implanted with six Willis covered stents.The occlusive rate and complication in the two kinds of stents were compared by postoperative follow-up and modified rankin score(MRS).Results:After the implantation of PED,four patients showed an immediate stagnation of blood flow or a decreased filling in aneurysms,three out of four patients exhibited complete occlusion,and the remaining patient had nearly complete occlusion.Four out of five cases of Willis stent implantation were associated with immediate complete occlusion of aneurysms,and the modified rankin score of these patients ranged from 0 to 1.One patient died of unassociated complications.Conclusion:For different types of TPIA in the internal carotid artery(ICA),PED and Willis stents provide significant advantages in treatment,with fewer postoperative complications and prognosis well.

Influence of the aspect ratio on the endovascular treatment of intracranial aneurysms: A computational investigation

Intracranial aneurysm, a localized dilation of arterial blood vessels in the Circle of Willis and its branches, is potentially life threatening, due to massive bleeding in the subarachnoid space upon rupture. In clinical practice, one minimally invasive surgical procedure is the implantation of a metallic stent to cover the aneurysm neck. This flow diverting device can reduce the flow into the aneurysm and enhance the prospect of thrombosis, a condition expected to reduce the risk of growth and rupture. The biomechanical and haemo-dynamic factors in stented and nonstented situations are studied by computational fluid dynamics. Unlike earlier models with straight or curved parent blood vessels, the aneurysm is now located near an arterial bifurcation. The influence of the aspect (depth to neck) ratio of the aneurysm on the flow dynamics will be emphasized, especially in the post-operation stages. More precisely, the maximum flow velocity, the variations of wall shear stress, the risk of stent migration and volumetric flow rate after endovascular treatment will be studied. Aneurysms with larger aspect ratios (i.e. smaller neck sizes for constant depth) generally pose a greater risk in terms of these flow parameters. These results will assist the applications and design of stents in future neurosurgical therapy. The approach is limited to a nonelastic model, without taking into account of questions like stent expansion and interaction with tissue.

Safety and efficacy of complete versus near-complete coiling in treatment of intracranial aneurysms

Objective:This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assisted coiling(SAC)of intracranial aneurysms.Methods:This retrospective study enrolled 390 patients(417 aneurysms).Among them,complete(100%)or nearcomplete(>90%)angiographic obliteration of the aneurysms on immediate angiography was accomplished.Baseline characteristics,complications,angiography follow-up results,and clinical outcomes were analyzed.Results:Cumulative adverse events occurred in 30 patients(7.7%),including thromboembolic complications in 17(4.4%),intraoperative rupture in 10(2.6%),and others in 3(0.8%).Statistical analyses revealed an increased intraprocedural rupture rate in the initial completely occluded aneurysms(5.6%compared with 1.0%).The incidence of cumulative adverse events was higher in patients with completely occluded aneurysms(11.1%)than in those with near-completely occluded aneurysms(5.5%).Angiography follow-up was available for 173 aneurysms.Aneurysm occlusion status at follow-up was correlated with stent placement(p?0.000,odds ratio?5.847),size(p?0.000,odds ratio?6.446 for tiny aneurysms;and p?0.001,odds ratio?5.616 for small aneurysms),and initial aneurysm occlusion status(p?0.001,odds ratio?3.436).Complete occlusion at followup was seen in 82.6%of the initial complete occlusion group versus 63.0%of the initial near-complete occlusion group.The incidence of complete occlusion at follow-up was higher in the initial completely occluded aneurysms with SAC(100%)than in the initial completely occluded aneurysms with non-SAC(65.2%).Conclusions:Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up.Stent placement may enhance progressive aneurysm occlusion.Initial complete occlusion with SAC can provide durable closure at follow-up.

The effects of stent porosity on the endovascular treatment of intracranial aneurysms located near a bifurcation

Intracranial aneurysm occurs when a cerebral artery develops an abnormal sac-like dilatation, and will cause massive bleeding in the subarachnoid space upon rupture. Endovascular stenting is a minimally invasive procedure in which a flow-diverting stent is deployed to cover the aneurysm neck, thereby restricting blood from entering the aneurysm and reducing the risk of rupture. The stent porosity, a crucial factor determining the intra-aneurysmal hemodynamics following treatment, is investigated by computational fluid dynamics techniques. Based on the computational results, a low porosity stent will dramatically reduce the flow velocity and the flow rate inside the side branch vessel. Conversely, a high porosity stent may not provide adequate flow reduction inside the aneurysm, possibly causing treatment failure. An advisable range of optimal stent porosity would be 60% to 75%, which can drastically reduce the flow rate into the aneurysm while preserving enough blood flow for the side branch vessel. Clinically, deployment of two or more flow-diverting stents may not increase treatment efficacy but can potentially lead to adverse effects due to side-branch hypoperfusion. The present quantitative analysis can also provide practical insight for future stent design.

Morphological characteristics associated with rupture risk of multiple intracranial aneurysms

Objective: To identify the morphological parameters that are related to intracranial aneurysms(IAs) rupture using a case-control model.Methods: A total of 107 patients with multiple IAs and aneurysmal subarachnoid hemorrhage between August 2011 and February 2017 were enrolled in this study.Characteristics of IAs location, shape, neck width, perpendicular height, depth, maximum size, flow angle, parent vessel diameter(PVD), aspect ratio(AR) and size ratio(SR) were evaluated using CT angiography.Multiple logistic regression analysis was used to identify the independent risk factors associated with IAs rupture.Receiver operating characteristic curve analysis was performed on the final model, and the optimal thresholds were obtained.Results: IAs located in the internal carotid artery(ICA) was associated with a negative risk of rupture, whereas AR, SR1(height/PVD) and SR2(depth/PVD) were associated with increased risk of rupture.When SR was calculated differently, the odds ratio values of these factors were also different.The receiver operating characteristic curve showed that AR, SR1 and SR2 had cut-off values of 1.01, 1.48 and 1.40, respectively.SR3(maximum size/PVD) was not associated with IAs rupture.Conclusions: IAs located in the ICA are associated with a negative risk of rupture, while high AR(>1.01), SR1(>1.48) or SR2(>1.40) are risk factors for multiple IAs rupture.

Superficial Temporal Artery to Middle Cerebral Artery Bypass and Endovascular Parent Artery Occlusion in the Treatment of Giant Intracranial Aneurysms

The authors are reporting on a study drawn from unpublished dissertation done by the corresponding author when he completed his neurosurgical training in Paris, France in 2004, few years before the advent of flow diverters. The study was a retrospective review of giant intracranial aneurysms treated by superficial temporal artery to middle cerebral artery bypass combined with endovascular occlusion of the parent artery. From 1990 to 2003, 29 consecutive cases of giant cerebral aneurysms, not suitable to selective treatment were managed in that way. Twenty-one medical records had enough data to allow objective evaluation. Sixteen female and five male patients bearing 21 giant aneurysms were involved. Their mean age was 46 years. The aneurysm was revealed by mass effect in 13 cases and subarachnoid hemorrhage in one case. On admission 19 patients presented with unruptured aneurysms and two have sustained a subarachnoid hemorrhage. The balloon occlusion test before the bypass operation was not tolerated in 18 patients. The treatment was completed in 19 patients and 17 of them had parent artery occlusion with latex detachable balloons. The only death of the series occurred before the endovascular treatment. The mean follow-up period was 30 months. After completion of the treatment, 16 (84%) patients had no symptom. Aneurysm recanalization or rupture was not observed after the parent artery occlusion. With the combination of superficial temporal artery to middle cerebral artery bypass + endovascular parent artery occlusion, 90% of giant intracranial aneurysms untreatable selectively were permanently excluded with a good outcome in 95%.

Developing a Scale for Measuring Uncertainty in Patients with Unruptured Intracranial Aneurysms Undergoing Endovascular Coiling

A measure called the Uncertainty in Unruptured Intracranial Aneurysm Patients Undergoing Endovascular Coiling Scale (UUIACS) was developed and its validity and reliability were examined. The 49 questions that comprised the original draft of the UUIACS were created based on interview data. Based on data from 172 participants, exploratory and confirmatory factor analyses were conducted. As a result of exploratory factor analysis, the UUIACS e retained 17 items and extracted four factors (“Lack of decision-making cues”, “Lack of information and complexity of information interpretation”, “The ambiguous nature of the disease”, and “The unpredictable living with UIA”). All of the UUIACS items showed adequate internal consistency. Between the UUIAC scale and the Universal Uncertainty in Illness Scale (UUIS), the Health Locus of Control (HLC) scale, and the SF-36v2&reg (Japanese version), positive correlations were found between the UUIACS and UUIS, and the HLC scale at a 1% significance level indicating concurrent validity. According to confirmatory factor analysis, the UUIACS had an acceptable goodness of fit. Given these findings, the UUIACS was judged to have satisfied the criteria for use in a clinical setting, although further investigation was required.

Mining and analysis of intracranial aneurysms formation and fracture-related genes based on Gene Expression Omnibus database

Objective: To explore potential genes associated with the formation and rupture of intracranial aneurysms based on the Gene Expression Omnibus (GEO) database. Methods: A total of 133 mRNA microarrays were collected from the GEO database. Differential mRNA gene analysis was performed on the data of each group in the GEO2R platform, and the common differential genes were screened and the gene ontology enrichment analysis and the Kyoto Gene and Genomic Encyclopedia pathway enrichment analysis were completed. The screened differential genes were introduced into the String online database to obtain the interaction between the proteins encoded by the differential genes. Results: Forty-two common differential genes were screened, and the main biological processes involved included the transcriptional regulation of oxidative stress, the positive regulation of chemokine production, and the positive regulation of autophagy of giant cells by RNA polymerase II promoter. Molecular functions included protein binding, RNA polymerase II transcriptional co-repressor activity, transcriptional activator activity, and protein kinase C binding. The main signal pathways covered included hypoxia-inducible factor-1 signaling pathway, glucagon signaling pathway, and metabolic pathway signaling pathway. Conclusions: The formation and rupture of the intracranial aneurysm may be initially screened with amidoxime reduction component 1, tumor necrosis factor-α-inducible protein 6, haptoglobin, mast cell membrane-expressing protein 1, zipper containing kinase, phospholipase Cβ4 and blood and nervous system expression factor-1. In addition to the previously knownintracranial aneurysms mechanisms, cellular autophagy and hypoxia inducible factor-1 pathway may also be involved in the formation of intracranial aneurysms.

Research progress in the causes of intracranial aneurysms

Subaracoid hemorrhage caused by intracranial aneurysms is characterized by high morbidity and mortality.There is no definite conclusion regarding the mechanism of formation,development,and rupture of intracranial aneurysms.It is generally believed to be related to congenital hereditary connective tissue diseases and acquired hemodynamic factors,vascular inflammation,and oral pathogens.In addition,gender,age,hypertension,and psychological status are also important factors.Relevant studies show a significantly lower quality of life in patients with intracranial aneurysms,and psychological factors should be studied in more depth.Neurological complications are considered an important factor in the decrease in quality of life.In conclusion,the formation,development,and rupture of intracranial aneurysms should result from a combination of congenital and acquired factors.

Microsurgical Management of Intracranial Aneurysms in Côte d’Ivoire: A Series of 128 Cases

Introduction: The management of intracranial aneurysms in sub-Saharan Africa is essentially surgical. In this retrospective study, the authors report their experience in surgical management of intracranial aneurysm in C&#244;te d’Ivoire. Methods: We carried out a retrospective study on patients operated for a ruptured or unruptured intracranial aneurysm between January 1st, 2012 and December 31st, 2018. Data on epidemiological characteristics of patients and aneurysms, treatments and patient outcomes were analyzed. Results: One hundred twenty eight aneurysms were operated. Sixty-six percent of the patients were female. According to the World Federation of Neurosurgical Societies (WFNS) scale, 58, 5% of patients were in grade I. Fisher scale showed 29% of Fisher 2 and 49% of Fisher 4. The aneurysms were mainly located on the internal carotid artery in 38% and anterior complex in 36%. The average size of aneurysms was 6.5 mm. In 81.4% the size of the aneurysms was less than 10 mm. Most aneurysms (90%) were treated at late stage. According to the modified Rankin Scale, 92 patients (83%) had good outcome, 7 patients (6%) had poor outcome, and the mortality rate was 11%. Conclusions: This study shows encouraging results if we refer to the overall postoperative results. However, there is a sub-diagnosis and low treatment rate of ruptured intracranial aneurysms. The improvement of intracranial aneurysms management requires improving the standard of health in the country.

Interventional therapy for intracranial aneurysms under neuroelectrophysiological monitoring

Objective To study the application of neuroelectrophysiological monitoring for interventional therapy of intracranial aneurysms. Methods 22 patients with intracranial aneurysm underwent neuroelectrophysiological monitoring during interventional therapy. Somatosensory evoked potential( SSEP) ,brainstem

Assisted coiling techniques in treatment of intracranial complex aneurysms

Objective To investigate the application of assisted coiling techniques in the treatment of complex intracranial aneurysms. Methods From Jun. 2007 to Aug. 2010,36 patients with 41 complex intracranial aneurysms were treated by varient endovascular methods,including balloon, stent-assisted coiling and double microcatheter coilingtechniques. Results Among the