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

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.

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.

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 Côte 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.

Risk factors and outcomes of postoperative stroke in surgical treatment for giant intracranial aneurysms

Background:Giant intracranial aneurysms(GIAs)are challenges for surgical treatment.Risk factors of postoperative stroke remain unclear.This study aims to investigate the predictors of postoperative stroke in GIAs and the impact of stroke on outcomes.Methods:We performed a retrospective medical record review of patients with GIAs who received microsurgery at our institution between 2011 and 2018.Multivariate logistic regression analyses were carried out to identify risk factors for postoperative stroke.The clinical and angiographic outcomes were compared between patients with and without stroke.Results:A total of 97 patients were included in this study.Surgical modalities included direct aneurysm neck clipping in 85 patients(87.7%),trapping with the bypass in 8(8.2%),proximal artery ligation in 1(1%),and bypass alone in 3(3.1%).Postoperative stroke was found in 26 patients(26.8%).Independent factors that affect postoperative stroke were recurrent aneurysm(OR,10.982;95%CI,1.976-61.045;P=0.006)and size≥3.5 cm(OR,3.420;95%CI,1.133-10.327;P=0.029).Combined perioperative mortality and morbidity was 26.8%.Follow-up was achieved from 89 patients(91.8%),with a mean follow-up period of 39 months(range 19 to 94 months).Good outcomes were observed in 75 patients(84.3%)and poor outcomes were observed in 14 patients(15.7%).Conclusions:Postoperative stroke was significantly associated with clinical outcome.Favorable outcomes can be achieved in most patients with GIAs after appropriate microsurgical modality.Recurrent aneurysm and size≥3.5 cm are risk factors of postoperative stroke.

Effects of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms

Background:This study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition,operative complications,embolization outcomes,and clinical outcomes.Methods:We retrospectively reviewed the medical records of patients with wide-necked intracranial aneurysms who underwent Enterprise 2 stent-assisted coiling in our hospital from November 2018 to October 2019.Intraoperative VasoCT was performed immediately after stent release in a continuous cohort of patients to observe stent-vessel apposition.Patient demographic,clinical,and imaging data were recorded and analyzed.Results:A total of 106 wide-necked aneurysms in 106 patients were treated.Stent release was successful in all patients.Twenty-one patients were enrolled consecutively for VasoCT scanning,and incomplete stent apposition was observed in 5(23.8%).Perioperative complications occurred in 10 patients(9.4%):cerebral infarction in 6,intraoperative coil prolapse in 1,puncture site pseudoaneurysm in 1,deep vein thrombosis at multiple sites in 1,and transient brainstem mass effect in 1.Among the 95 aneurysms with angiographic follow-up,embolization was satisfactory(Raymond-Roy classifications I and II)in 89(93.7%).Hyperlipidemia was an independent risk factor for incomplete aneurysm occlusion.At the last clinical follow-up,seven patients had a poor clinical outcome(modified Rankin Scale score≥3).Independent risk factors for poor outcomes were preoperative subarachnoid hemorrhage at presentation and cerebral infarction.Conclusion:Enterprise 2 stent-assisted coiling for treatment of wide-necked intracranial aneurysms showed good safety and efficacy;however,incomplete stent apposition can still occur in vessels with a large curvature.Preoperative subarachnoid hemorrhage at presentation and cerebral infarction are the main reasons for poor clinical outcomes after stent-assisted coil embolization.

A two-step surface-based 3D deep learning pipeline for segmentation of intracranial aneurysms

The exact shape of intracranial aneurysms is critical in medical diagnosis and surgical planning.While voxel-based deep learning frameworks have been proposed for this segmentation task,their performance remains limited.In this study,we offer a two-step surface-based deep learning pipeline that achieves significantly better results.Our proposed model takes a surface model of an entire set of principal brain arteries containing aneurysms as input and returns aneurysm surfaces as output.A user first generates a surface model by manually specifying multiple thresholds for time-of-flight magnetic resonance angiography images.The system then samples small surface fragments from the entire set of brain arteries and classifies the surface fragments according to whether aneurysms are present using a point-based deep learning network(PointNet++).Finally,the system applies surface segmentation(SO-Net)to surface fragments containing aneurysms.We conduct a direct comparison of the segmentation performance of our proposed surface-based framework and an existing voxel-based method by counting voxels:our framework achieves a much higher Dice similarity(72%)than the prior approach(46%).

Validation of the predictive accuracy of"clinical+morphology nomogram"for the rebleeding risk of ruptured intracranial aneurysms after admission

Background:Rebleeding can cause a catastrophic outcome after aneurysmal subarachnoid hemorrhage.A clinical+morphology nomogram was promoted in our previous study to assist in discriminating the rupture intracranial aneurysms(RIAs)with a high risk of rebleeding.The aim of this study was to validate the predictive accuracy of this nomogram model.Method:The patients with RIAs in two medical centers from December 2020 to September 2021 were retrospectively reviewed,whose clinical and morphological parameters were collected.The Cox regression model was employed to identify the risk factors related to rebleeding after their admission.The predicting accuracy of clinical+morphological nomogram,ELAPSS score and PHASES score was compared based on the area under the curves(AUCs).Results:One hundred thirty-eight patients with RIAs were finally included in this study,20 of whom suffering from rebleeding after admission.Hypertension(hazard ratio(HR),2.54;a confidence interval of 95%(CI),1.01-6.40;P=0.047),bifurcation(HR,3.88;95%CI,1.29-11.66;P=0.016),and AR(HR,2.68;95%CI,1.63-4.41;P<0.001)were demonstrated through Cox regression analysis as the independent risk factors for rebleeding after admission.The clinical+morphological nomogram had the highest predicting accuracy(AUC,0.939,P<0.01),followed by the bifurcation(AUC,0.735,P=0.001),AR(AUC,0.666,P=0.018),and ELAPSS score(AUC,0.682,P=0.009).Hypertension(AUC,0.693,P=0.080)or PHASES score(AUC,0.577,P=0.244)could not be used to predict the risk of rebleeding after admission.The calibration curve for the probability of rebleeding showed a good agreement between the prediction through clinical+morphological nomogram and actual observation.Conclusion:Hypertension,bifurcation site,and AR were independent risk factors related to the rebleeding of RIAs after admission.The clinical+morphological nomogram could help doctors to identify the high-risk RIAs with a high predictive accuracy.

Using the modified Delphi method to research the influencing factors of longterm health-related quality of life in patients with unruptured intracranial aneurysms after endovascular treatment

Background:The purpose of this study was to use the modified Delphi method to identify the influencing factors of health-related quality of life(HRQoL)in patients with unruptured intracranial aneurysms(UIAs)after endovascular treatment.Methods:A modified Delphi method to obtain expert consensus on the content of potential influencing factors of HRQoL in patients with UIAs treated by endovascular intervention was employed.The research team consists of three neuroradiologists and one epidemiologist from Xuanwu Hospital of Capital Medical University.They randomly selected 21 well-known experts in cerebrovascular disease diagnosis and treatment as participating experts.The importance of the indicator is based on the 5-Likert scale.The standard deviation(SD),coefficient of variation(CV),mean(x),and minimum and maximum scores of each indicator were calculated.The consistency was described by Kendall coefficient of concordance with a p value<0.05 indicating that the expert consistency was high.Result:Twenty-one and 18 questionnaires were responded in 2 rounds,with effective response rates of 85.7%and 100.0%,respectively.The average authoritative coefficient(Cr)of all 21 experts was 0.88,familiarity with the indicators(Cs)was 0.82,and the judgment basis of the indicators(Ca)was 0.94.Eventually,the x values of arterial puncture hematoma,hyperlipidemia,gender,marital status,and hospitalization for other diseases were lower than 3.5;CV for marital status and gender was higher than 0.35.The Kendall coefficient of concordance in the first round was 0.19(p<0.001),and the second round was 0.15(p<0.001).Conclusion:In this study,the factors affecting the recovery of HRQoL after endovascular treatment in patients with UIAs were analyzed by the modified Delphi method,which provided a valuable evidence for the clinical management and daily life guidance for UIAs patients.

Hemodynamics,inflammation,vascular remodeling,and the development and rupture of intracranial aneurysms:a review

The central nervous system is an immunologically active environment where several components of the immune and inflammatory response interact among them and with the constituents of nervous tissue and vasculature in a critically orchestrated manner,influencing physiologic and pathologic processes.In particular,inflammation takes a central role in the pathogenesis of intracranial aneurysms(IAs).The common pathway for aneurysm formation involves endothelial dysfunction and injury,a mounting inflammatory response,vascular smooth muscle cells(VSMCs)phenotypic modulation,extracellular matrix remodeling,and subsequent cell death and vessel wall degeneration.We conducted a literature review(1980-2014)by Medline and EMBASE databases using the searching terms“IA”and“cerebral aneurysm”and further search was performed to link the search terms with the following key words:inflammation,hemodynamic(s),remodeling,macrophages,neutrophils,lymphocytes,complement,VSMCs,mast cells,cytokines,and inflammatory biomarkers.The aim of this review was to summarize the most recent and pertinent evidences regarding the articulated processes of aneurysms formation,growth,and rupture.Knowledge of these processes may guide the diagnosis and treatment of these vascular malformations,the most common cause of subarachnoid hemorrhage,which prognosis remains dismal.

Risk factors for periprocedural ischemic stroke following endovascular treatment of intracranial aneurysms

Background:The aim of this study was to comprehensively evaluate the risk factors of periprocedural ischemic stroke associated with endovascular treatment of intracranial aneurysms using a real-world database.Methods:From August 2016 to March 2017,167 patients were enrolled.Univariate analysis and multivariate logistic regression analysis were used to examine the risk factors for periprocedural ischemic stroke.Results:Among the 167 cases,periprocedural ischemic stroke occurred in 20 cases(11.98%).After univariate analysis,the ischemic group had a higher proportion of large(≥10 mm)aneurysms than the control group(45.0%vs.23.1%,p=0.036).The incidence of periprocedural ischemic stroke was higher in cases treated by flow diverter(21.6%)or stent-assisted coiling(11.8%)than in cases treated by coiling only(2.7%),and the differences were statistically significant(p=0.043).After multivariate logistic regression analysis,treatment modality was the independent risk factor for periprocedural ischemic stroke.Compared with the coiling-only procedure,flow diverter therapy was associated with a significantly higher rate of periprocedural ischemic stroke(OR 9.931;95%CI 1.174-84.038;p=0.035).Conclusions:Aneurysm size and treatment modality were associated with periprocedural ischemic stroke.Larger aneurysms were associated with increased risk of periprocedural ischemic stroke.Flow diverter therapy was associated with significantly more periprocedural ischemic stroke than the coiling procedure alone.

Endovascular coiling versus microsurgical clipping for ruptured intracranial aneurysms:a meta-analysis and systematic review

Background:The purpose of this analysis is to evaluate the current evidence with regard to the effectiveness and safety between coiling and clipping in patients with ruptured intracranial aneurysms(RIAs).Methods:We performed a meta-analysis that compared clipping with coiling between July 2000 and September 2021.PubMed,EMBASE,and the Cochrane Library were searched for related articles systematically.And the treatment efficacy and postoperative complications were analyzed.Results:We identified three randomized controlled trials and thirty-seven observational studies involving 60,875 patients with ruptured cerebral aneurysms.The summary results showed that coiling was related a better quality of life(mRS0-2;OR=1.327;CI=1.093-1.612;p<0.05),a higher risk of mortality(OR=1.116;CI=1.054-1.180;p<0.05),higher rate of rebleeding(RR=1.410;CI=1.092-1.822;p<0.05),lower incidence of vasospasm(OR=0.787;CI=0.649-0.954;p<0.05),higher risk of hydrocephalous(RR=1.143;CI=1.043-1.252;p<0.05),lower risk of cerebral infarction(RR=0.669;CI=0.596-0.751;p<0.05),lower risk of neuro deficits(RR=0.720;CI=0.582-0.892;p<0.05),and a lower rate of complete occlusion(OR=0.495;CI=0.280-0.876;p<0.05).Conclusion:Coiling was significantly associated with a better life quality(mRS0-2),a lower incidence of postoperative complications,and a higher rate of mortality,rebleeding,hydrocephalous,and a lower rate of complete occlusion than clipping.

Expert Consensus on Assessment of Rupture Factors in Unruptured Intracranial Aneurysms

Intracranial aneurysms have a high prevalence in the population and are associated with high rates of disability and mortality after rupture.It is essential to assess the rupture risk of unruptured intracranial aneurysms by selecting appropriate morphological parameters.However,there is still a need for consistent evidence-based medicine to provide a clinical reference.Therefore,the expert group has jointly written this consensus based on literature review and clinical experience,aiming to provide a standardized reference for predicting the development of intracranial aneurysms and evaluating their rupture risk factors.

Safety and efficacy of stent-assisted coiling for acutely ruptured wide-necked intracranial aneurysms:comparison of LVIS stents with laser-cut stents

Background:To compare the safety and efficacy of LVIS stent-assisted coiling with those of laser-cut stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms.Methods:Patients with acutely ruptured wide-necked intracranial aneurysms treated with LVIS stent-assisted coiling(LVIS stent group)and laser-cut stent-assisted coiling(laser-cut stent group)were retrospectively reviewed from January 2014 to December 2017.Propensity score matching was used to adjust for potential differences in age,sex,aneurysm location,aneurysm size,neck width,Hunt-Hess grade,and modified Fisher grade.Perioperative procedure-related complications and clinical and angiographic follow-up outcomes were compared.Univariate and multivariate analyses were performed to determine the associations between procedure-related complications and potential risk factors.Results:A total of 142 patients who underwent LVIS stent-assisted coiling and 93 patients who underwent laser-cut stent-assisted coiling were enrolled after 1:2 propensity score matching.The angiographic follow-up outcomes showed that the LVIS stent group had a slightly higher complete occlusion rate and lower recurrence rate than the laser-cut stent group(92.7%vs 80.6%;3.7%vs 9.7%,P=0.078).The clinical outcomes at discharge and follow-up between the two groups demonstrated no significant differences(P=0.495 and P=0.875,respectively).The rates of intraprocedural thrombosis,postprocedural thrombosis,postoperative early rebleeding,and procedure-related death were 0.7%(1/142),1.4%(2/142),2.8%(4/142),and 2.1%(3/142)in the LVIS stent group,respectively,and 4.3%(4/93),2.2%(2/93),1.1%(1/93),and 3.2%(3/93)in the laser-cut stent group,respectively(P=0.082,0.649,0.651,and 0.683).Nevertheless,the rates of overall procedure-related complications and intraprocedural rupture in the LVIS stent group were significantly lower than those in the laser-cut stent group(5.6%vs 14.0%,P=0.028;0.7%vs 6.5%,P=0.016).Multivariate analysis showed that laser-cut stent-assisted coiling was an independent predictor for overall procedurerelated complications(OR=2.727,P=0.037);a history of diabetes(OR=7.275,P=0.027)and other cerebrovascular diseases(OR=8.083,P=0.022)were independent predictors for ischemic complications,whereas none of the factors were predictors for hemorrhagic complications.Conclusions:Compared with laser-cut stent-assisted coiling,LVIS stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms could reduce the rates of overall procedure-related complications and intraprocedural rupture.

Hemodynamic analysis for endovascular treatment in small unruptured intracranial aneurysms:a matched comparison study of flow diverter versus LVIS

Background:We compared the treatment of small unruptured intracranial aneurysms(UIAs)with flow diverter and LVIS-assisted coiling to determine the effects of hemodynamic changes caused by different stent and coil packing in endovascular treatment.Methods:Fifty-one UIAs in 51 patients treated with pipeline embolization device(PED)were included in this study and defined as the PED group.We matched controls 1:1 and enrolled 51 UIAs who were treated with LVIS stent,which were defined as the LVIS group.Computational fluid dynamics were performed to assess hemodynamic alterations between PED and LVIS.Clinical analysis was also performed between these two groups after the match.Results:There was no difference in procedural complications between the two groups(P=0.558).At the first angiographic follow-up,the complete occlusion rate was significantly higher in the LVIS group compared with that in the PED group(98.0%vs.82.4%,P=0.027).However,during the further angiographic follow-up,the complete occlusion rate in the PED group achieved 100%,which was higher than that in the LVIS group(98.0%).Compared with the LVIS group after treatment,cases in the PED group showed a higher value of velocity in the aneurysm(0.03±0.09 vs.0.01±0.01,P=0.037)and WSS on the aneurysm(2.32±5.40 vs.0.33±0.47,P=0.011).Consequently,the reduction ratios of these two parameters also showed statistical differences.These parameters in the LVIS group showed much higher reduction ratios.However,the reduction ratio of the velocity on the neck plane was comparable between two groups.Conclusions:Both LVIS and PED were safe and effective for the treatment of small UIAs.However,LVIS-assisted coiling produced greater hemodynamic alterations in the aneurysm sac compared with PED.The hemodynamics in the aneurysm neck may be a key factor for aneurysm outcome.

Computational fluid dynamics simulation of intracranial aneurysms-comparing size and shape

Objective:To study the hemodynamics of an anatomic internal carotid artery aneurysm derived from a patient-specific model and then manipulate into two phantom morphologies:one growing uniformly by size and the other changing shape unevenly.Methods:The computational model of the saccular,internal carotid artery,aneurysm was constructed from 3D rotational,digitally subtracted,catheter angiography images.Computational fluid dynamics simulations were performed under pulsatile cardiac flow conditions.Velocity vectors,streamlines,pressure,and wall shear stress(WSS)and its variance distributions were quantitatively visualized.Results:The maximum pressure and WSS from the time-averaged distribution on the inside saccular surface of the original case are 415.38 and 17.61 Pa.In contrast,the bi-lobed shape gives rise to higher peak values of pressure(461.00 Pa)and WSS(33.20 Pa)on the saccular dome.Conversely,the evenly enlarged aneurysm actually results in a slightly lower peak pressure(399.58 Pa)and drastically decreased WSS(9.81 Pa).Conclusions:The current study indicates that the size of the aneurysm should not be the only determining factor for the rupture risk consideration,the irregularity of the aneurysm shape and the corresponding aberrant hemodynamics might be a more important factor to consider for risk assessment.

Mechanical compression management of the right middle cerebral artery inferior trunk using a stent during coil embolization of middle cerebral artery aneurysms:A case report and literature review

Endovascular coil embolization is a minimally invasive,rapid,and effective method for the treatment of intracranial aneurysms.However,complications associated with coil embolization,such as intraoperative aneurysm rupture or arterial occlusion,should be promptly managed during the procedure to avoid catastrophic consequences.This study presents a case of mechanical compression management of the right middle cerebral artery(MCA)inferior trunk during coil embolization for bilateral MCA aneurysms.The inferior trunk of the right MCA was abruptly occluded due to mechanical compression during coil embolization of the right MCA bifurcation aneurysm.A Solitaire AB stent(4×20 mm,Covidien/Medtronic,Dublin,Ireland)was implanted in the inferior trunk of the right MCA after tirofiban was injected via a microcatheter,and the right inferior trunk was recanalized.The patient also underwent coil embolization of the left MCA bifurcation aneurysm,without any complications.It is crucial to recognize compressive occlusion of adjacent aneurysm branches to avoid severe complications during intracranial aneurysm embolization.Stent placement is a rescue treatment option for recanalization of an occluded artery.

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.