Endovascular treatment of symptomatic severe intracranial atherosclerotic stenosis with a novel intracranial dedicated drug-eluting stent: a more effective treatment approach

Background

Endovascular treatment of severe intracranial atherosclerotic stenosis (ICAS) using coronary drug-eluting stents (DESs) significantly reduces the risk of in-stent restenosis (ISR) and stroke recurrence. However, there are few reports regarding the treatment of ICAS with intracranial dedicated DES. Herein, we present our experience with the feasibility, safety, and medium-term follow-up outcomes of a novel intracranial DES, named NOVA stent, in patients with symptomatic severe ICAS (≥70%).

Methods

From December 2021 to May 2022, patients with symptomatic severe ICAS who underwent implantation of the NOVA stent in our institution were retrospectively analyzed for procedural results, perioperative complications, imaging and clinical follow-up outcomes.

Results

Twenty-four patients, 16 (66.7%) with anterior circulation lesions and 8 (33.3%) with posterior circulation lesions, were enrolled. All patients with intracranial ICA (n = 6), middle cerebral artery (n = 10), basilar artery (n = 3), intracranial vertebral artery (n = 3), and the vertebrobasilar junction (n = 2) stenosis were treated successfully using NOVA stents. The severity of stenosis ranged from 75 to 96% (mean 85.9%) before treatment and this was reduced to 0 to 20% (mean 8.6%) immediately after stent placement. Symptomatic distal embolism occurred in one case; however, there were no other perioperative complications. The mean follow-up duration was 12.2 ± 1.06 months. No symptomatic ischemic events occurred during follow-up. Follow-up cerebral angiography was performed in 22 of 24 patients (91.7%), and significant ISR occurred in one patient (4.2%).

Conclusion

Our results demonstrate that implantation of the novel intracranial DES NOVA in severe ICAS is feasible, safe, and effective in selected cases, reducing the incidence of ISR, and showing excellent midterm clinical outcomes, providing a promising option for ICAS treatment.

The short-term outcome of intracranial stenosis with distal thrombosis treated with balloon-assisted tracking

Background and purposes

Treating intracranial stenosis with distal thrombosis (IS&DT) using traditional mechanical thrombectomy (MT) techniques has proven challenging. This study aimed to summarize the experience of utilizing the balloon-assisted tracking (BAT) technique for IS&DT.

Methods

Demographic and morphologic characteristics of patients with IS&DT were collected for this study. The BAT technique, involving a half-deflated balloon outside the intermediate catheter tip, was used in all patients to navigate through the proximal stenosis. Various parameters were recorded, including the sequence of vascular reperfusion, the puncture-to-reperfusion time (PRT), the residual stenosis rate, and the occurrence of re-occlusion. The thrombolysis in cerebral infarction (TICI) scale was used to assess the reperfusion of intracranial vessels, with a TICI score of ≥2b considered as successful perfusion. The clinical status of patients was evaluated at three time points: pre-procedure, post-procedure, and at discharge using the modified Rankin score (mRS).

Results

In this study, a total of 10 patients were diagnosed with IS&DT, consisting of 9 male patients (90.0%) and 1 female patient (10.0%). The patients' mean age was 63.10 years (ranging from 29 to 79 years). The mean National Institute of Health Stroke Scale (NIHSS) score before treatment was 24.3 (ranging from 12 to 40), indicating the severity of their condition. Following the procedure, all patients achieved successful reperfusion with a thrombolysis in cerebral infarction (TICI) score of ≥2b. The average puncture-to-reperfusion time (PRT) was 51.8 min (ranging from 25 to 100 min), indicating the time taken for the procedure. During the perioperative period, three patients (30.0%) experienced complications. One patient had hemorrhage, while two patients had contrast extravasation. Among these cases, only the patient with hemorrhage (10%) suffered from a permanent neurological function deficit. At discharge, the patient's condition showed improvement. The mean NIHSS score decreased to 13.2 (ranging from 1 to 34), indicating a positive response to treatment. The mean mRS score at discharge was 3.2 (ranging from 1 to 5), showing some level of functional improvement.

Conclusion

In conclusion, the use of the balloon-assisted tracking (BAT) technique for treating intracranial stenosis with distal thrombosis (IS&DT) showed promising results. However, a moderate rate of perioperative complications was observed, warranting further investigation and refinement of the procedure.

Giant Cell Arteritis Presenting as Multiple Ischaemic Strokes: A Successful case of Endovascular Treatment

Giant cell arteritis (GCA) may manifest with aggressive intracranial stenosis resistant to medical therapy, and patients may develop refractory neurologic deficits and cerebral infarcts, making GCA a life-threatening condition. We report the case of a 68-year-old woman recently diagnosed with GCA, medicated with prednisolone 60 mg daily. Two weeks later, the patient was admitted to our Stroke Unit after a sudden episode of global aphasia. Magnetic resonance angiography showed two recent ischaemic lesions, besides an erythrocyte sedimentation rate of 17 mm/hour. A cerebral angiography revealed bilateral stenosis and dilation in the petrous, cavernous and supraclinoid segments of internal carotid arteries (ICA). The patient was started on intravenous methylprednisolone pulses (250 mg daily for five days). Computed tomography (CT) angiography and Doppler ultrasound showed severe vascular disease affecting multiple territories, without significant intracranial involvement. The hypothesis of GCA with extracranial vasculitic involvement was considered as the aetiology of ischaemic cerebral infarctions in multiple territories and, given the severity of the disease, it was decided to add tocilizumab. Despite this, the patient evolved with significant worsening neurological deficits and a CT scan confirmed the presence of new vascular events. Endovascular treatment (EVT) with balloon angioplasty was conducted on both ICAs, with improved calibre and downstream filling. After that, the patient presented sustained clinical improvement, without recurrence of any ischaemic events at the one-year follow-up. This clinical case stands out for the importance of EVT as an effective therapy in patients with medically refractory GCA with symptomatic intracranial stenosis, improving their prognosis.

LEARNING POINTS

Giant cell arteritis may manifest with aggressive and symptomatic intracranial arterial stenoses.Endovascular treatment is an effective intervention to prevent ischaemic complications in intracranial giant cell arteritis.

Self-expanding versus balloon expandable stent for intracranial arterial stenosis: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

There are limited data regarding the comparison of balloon expandable stents (BES) and self-expanding stents (SES) for the treatment of intracranial arterial stenosis.

METHODS

We conducted a systematic review to identify studies that compared SES and BES in patients with symptomatic intracranial arterial stenosis. Data were extracted from relevant studies found through a search of PubMed, Scopus, and Web of Science until from January 1, 2010 to September 28, 2023. Statistical pooling with random-effects meta-analysis was undertaken to compare the rates/severity of postprocedure stenosis, technical success, 30-day stroke and/or death, cumulative clinical endpoints, and restenosis rates.

RESULTS

A total of 20 studies were included. The standardized mean difference (SMD) for postprocedure stenosis (%) was significantly lower (SMD: -0.52, 95% confidence interval [CI]: -0.79 to -0.24, p < .001, 10 studies involving 1515 patients) with BES. The odds for 30-day stroke and/or death were significantly lower (odds ratio [OR] 0.68, 95% CI: 0.50-0.94, p = .019, 15 studies involving 2431 patients), and cumulative clinical endpoints on follow-up were nonsignificantly lower (OR 0.64, 95% CI: 0.30-1.37, p = .250, 10 studies involving 947 patients) with BES. The odds for restenosis during follow-up were significantly lower (OR 0.50, 95% CI: 0.31-0.80, p = .004, 13 studies involving 1115 patients) with BES.

CONCLUSIONS

Compared with SES, BES were associated with lower rates of postprocedure 30-day stroke and/or death with lower rates of restenosis during follow up and the treatment of symptomatic intracranial arterial stenosis.

Management strategies of unanticipated intracranial stenosis during mechanical thrombectomy for acute stroke: A survey of academic neurointerventionalists

BACKGROUND

The optimal approach to the management of intracranial atherosclerotic disease (ICAD) at the time of mechanical thrombectomy (MT) for large vessel occlusion (LVO) remains controversial. The goal of this study is to characterize current practices concerning this challenging clinical situation in a survey of practicing neurointerventionalists.

METHODS

An electronic questionnaire was sent to a cross-section of North American academic neurointerventionalists using publicly available contact information and departmental websites. Prior to analysis, responses were anonymized and categorized by region.

RESULTS

A total of 136/360 responses were recorded from the U.S. and Canada. The mean number of years of practicing as a neurointerventionalist among the respondents was 10.5 (± 6.2 years). ICAD was perceived as a causative factor during MT for LVO in 5-10% of thrombectomy cases. The most common first-line treatment approach for significant ICAD, assuming a TICI 2b or better reperfusion, was medical therapy (77.9% of respondents), followed by angioplasty + stent placement (8.8% of respondents). There were no significant differences in the first line treatment of ICAD in LVO between geographical regions (p = 0.815).

CONCLUSION

The approach to underlying ICAD in LVO varies widely; however, the majority of neurointerventionalists prefer medical therapy with DAPT as a first-line treatment approach. The current survey highlights the need for studies that better define the optimal timing and modality of treatment, along with an evidence-based framework for balancing the risks associated with these treatment approaches.

A Novel Window Into Human Vascular Remodeling and Diagnosing Carotid Flow Impairment: The Petro-Occipital Venous Plexus

Background Adaptive arterial remodeling caused by flow reduction from downstream stenosis has been demonstrated in animal studies. The authors sought to determine whether inward remodeling from downstream stenosis also occurs in humans and is detectable by ex vacuo expansion of the Rektorzik venous plexus (RVP) surrounding the petrous internal carotid artery. Methods and Results The authors analyzed 214 intracranial magnetic resonance imaging examinations that included contrast-enhanced vessel wall imaging. RVP symmetry was qualitatively assessed on vessel wall imaging. RVP thickness (RVPT) was measured on the thicker side if asymmetric or randomly assigned side if symmetric. Maximum stenosis (M1 or intracranial internal carotid artery) was measured. Posterior communicating artery and A1 diameters (>1.0 mm and 1.5 mm, respectively) defined adequate collateral outflow when proximal to the stenosis. Seventy-two patients had stenosis downstream from RVPT measurements. For those without adequate outflow (38 of 72), 95.0% with RVPT ≥1.0 mm had ≥50% stenosis compared with only 5.6% with RVPT <1.0 mm. For these 72 patients, higher RVPT (RVPT ≥1.0 mm versus <1.0 mm) and absent adequate outflow were associated with greater downstream stenosis (P<0.001) using multivariate regression. For patients with downstream stenosis without adequate outflow, asymmetric RVP thickening was associated with greater ipsilateral stenosis (P<0.001, all had ≥46% stenosis) when stenosis was unilateral and greater differences in stenosis between sides (P=0.005) when stenosis was bilateral. Conclusions Inward internal carotid artery remodeling measured by RVPT or RVP asymmetry occurs as downstream stenosis approaches 50%, unless flow is preserved through a sufficiently sized posterior communicating artery or A1, and may serve as a functional measure of substantial flow reduction from downstream stenosis.

Intracranial stenting versus aggressive medical therapy for symptomatic intracranial stenosis: A meta-analysis of multicenter randomized controlled trials and an expert assessment of the current data

BACKGROUND

Intracranial atherosclerotic stenosis (ICAS) is associated with high risk of recurrent strokes despite best medical management (MM). We aimed to synthesize the evidence from randomized studies comparing intracranial stenting plus MM versus MM alone.

METHODS

Comprehensive search of MEDLINE database was performed until May 2023. The data were extracted and pooled as risk ratio (RR) with 95% confidence interval (95% CI).

RESULTS

We included three multicenter RCTs totaling 919 patients. As compared to MM alone, intracranial stenting was associated with statistically significant higher risks of any stroke or death (RR = 2.93, 95%CI [1.80-4.78], p < 0.0001), stroke in the same territory of qualifying artery (RR = 3.56, 95%CI [1.97-6.44], p < 0.0001), any ischemic stroke (RR = 2.22, 95%CI [1.27-3.87], p = 0.005), hemorrhagic stroke (RR = 13.49, 95%CI [2.59-70.15], p = 0.0002), and death (RR = 5.43, 95%CI [1.21-24.40], p = 0.003) within 30 days of randomization. There was a persistent lack of benefit and signals of harm at the last follow up within 1-3 years: any stroke or death (RR = 1.57, 95%CI [0.92-2.67], p = 0.1), stroke in the same territory of qualifying artery (RR = 1.84, 95%CI [0.97-3.50], p = 0.06), any ischemic stroke (RR = 1.56, 95%CI [1.11-2.20], p = 0.01), death (RR = 1.61, 95%CI [0.77-3.38], p = 0.2). The cumulative rate of stroke in the same territory of qualified artery with MM alone within the 1-3-year follow up was lower than expected, with only 47 out of the 450 (10.4%) MM alone patients suffering such events.

CONCLUSION

The findings from this meta-analysis do not recommend stenting as a routine care option for the broader symptomatic ICAS patient population. The rates of recurrent strokes in ICAS patients managed with aggressive MM do not seem to be as high as anticipated. Additional multicenter RCTs including safer devices, larger sample sizes, and patients at higher risk of recurrent events are warranted.

Exploring Gender Disparities in the Prevalence and Clinical Characteristics of Atherosclerotic Cranial Stenosis

Background Atherosclerotic cranial stenosis (ACS) is a significant contributor to vascular events, including ischemic strokes. While early clinical studies suggested a divergence in the distribution of intracranial and extracranial stenosis between genders, recent evidence has highlighted the complexity of these disparities. Therefore, this study aims to investigate gender differences in the prevalence and clinical characteristics of atherosclerotic cranial stenosis in patients admitted with stroke. Methods This cross-sectional study was conducted at a tertiary care hospital located in the Southern Region of Saudi Arabia between June 2022 and December 2022. It included patients of all age groups who had been diagnosed with an ischemic stroke during the study period. Data were collected from electronic health records and medical archives, and data analysis was performed using Statistical Package for the Social Sciences (SPSS version 26, IBM Inc., Chicago, IL, USA). Results In our study, 201 stroke patients were analyzed, with 161 (80.09%) identified as having atherosclerotic stenosis. Of these, 57.8% were male, and 42.2% were female. Gender disparities were evident, with higher stenosis prevalence in males (46.27% vs. 33.83% in females). Significant gender differences were observed in dyslipidemia (p = 0.013), metabolic syndrome (p = 0.019), and smoking habits (p < 0.001). Males exhibited higher rates of extracranial stenosis (p = 0.012) and combined stenosis (p = 0.009) compared to females; however, females exhibited higher rates of intracranial stenosis (p = 0.013). Further analyses revealed significant associations in dyslipidemia (adjusted odd ratio (AOR): 0.245, p = 0.004), metabolic syndrome (AOR: 5.159, p = 0.006), obesity (AOR: 8.085, p = 0.016), smoking habits (AOR: 0.002, p < 0.001), and intracranial stenosis (AOR: 5.667, p = 0.005) within the female cohort. Conversely, age, hypertension, diabetes mellitus, ischemic heart disease, and extracranial stenosis did not show statistically significant associations in females (p > 0.05). Conclusion We observed a substantial presence of atherosclerotic cranial stenosis, with males showing higher rates, and identified significant gender-related variations in dyslipidemia, metabolic syndrome, and smoking habits as important factors. This highlights the necessity of tailoring ACS assessment and treatment by considering gender-specific risk factors and clinical characteristics for improved patient care and stroke management.

Frequency, Risk Factors, and Outcomes of Intracranial Atherosclerotic Stenosis in Stroke Patients From the Southern Region of Saudi Arabia

Background Intracranial Atherosclerotic Stenosis (ICAS) represents a noteworthy cerebrovascular pathology linked to ischemic stroke, contributing to a considerable burden of morbidity and mortality on a global scale. The present study was undertaken with the primary objective of investigating the frequency, risk factors, and outcomes of ICAS in stroke patients within the Southern Region of Saudi Arabia. Methods This was a descriptive cross-sectional study conducted at a tertiary care hospital located in the southern region of Saudi Arabia, from June 2022 to December 2022. The study population consisted of patients aged 18 years and above who were diagnosed with acute ischemic stroke during the designated research period. Patients with hemorrhagic stroke, transient ischemic attack (TIA), or incomplete medical records were excluded from the analysis. Data pertaining to the patients were retrieved from their respective medical records. Results Out of 201 patients admitted with stroke, 92 (45.77%) were found to have intracranial stenosis. The majority of patients were female (52.2%) and aged over 55 years (60.9%). The presence of hypertension exhibited a statistically significant correlation with varying degrees of stenosis (p=0.02), as did ischemic heart disease and obesity (p=0.04) and active smoking (p=0.01). Hypertension displayed a marginal association with intracranial stenosis, with an odds ratio of 1.01 (95% CI: 0.25, 4.11) and a p-value of 0.02. Similarly, dyslipidemia showed a potential correlation, with an odds ratio of 1.16 (95% CI: 0.44, 3.03) and a p-value of 0.014. On the other hand, obesity showed a stronger association, with an odds ratio of 4.53 (95% CI: 1.05, 19.51) and a p-value of 0.04. Among the patients, 25 (27.17%) underwent revascularization procedures, while 44 (47.83%) were not eligible for such intervention. During the three-month follow-up, 4 (16%) experienced an ipsilateral stroke, and 3 (12%) suffered from a contralateral transient ischemic attack (TIA). Encouragingly, 18 (72%) of the treated patients showed no recurrence during the follow-up period. Conclusion This study concludes that approximately half (45.77%) of stroke patients had intracranial stenosis, and significant associations were found between varying degrees of stenosis and hypertension, ischemic heart disease, obesity, and active smoking. Hypertension demonstrated a marginal correlation, while obesity exhibited a stronger association with intracranial stenosis.

Rescue therapy after thrombectomy for large vessel occlusion due to underlying atherosclerosis: review of literature

In this review article, we summarized the current advances in rescue management for reperfusion therapy of acute ischemic stroke from large vessel occlusion due to underlying intracranial atherosclerotic stenosis (ICAS). It is estimated that 24-47% of patients with acute vertebrobasilar artery occlusion have underlying ICAS and superimposed in situ thrombosis. These patients have been found to have longer procedure times, lower recanalization rates, higher rates of reocclusion and lower rates of favorable outcomes than patients with embolic occlusion. Here, we discuss the most recent literature regarding the use of glycoprotein IIb/IIIa inhibitors, angioplasty alone, or angioplasty with stenting for rescue therapy in the setting of failed recanalization or instant/imminent reocclusion during thrombectomy. We also present a case of rescue therapy post intravenous tPA and thrombectomy with intra-arterial tirofiban and balloon angioplasty followed by oral dual antiplatelet therapy in a patient with dominant vertebral artery occlusion due to ICAS. Based on the available literature data, we conclude that glycoprotein IIb/IIIa is a reasonably safe and effective rescue therapy for patients who have had a failed thrombectomy or have residual severe intracranial stenosis. Balloon angioplasty and/or stenting may be helpful as a rescue treatment for patients who have had a failed thrombectomy or are at risk of reocclusion. The effectiveness of immediate stenting for residual stenosis after successful thrombectomy is still uncertain. Rescue therapy does not appear to increase the risk of sICH. Randomized controlled trials are warranted to prove the efficacy of rescue therapy.

Thirty-Day Outcomes of Resolute Onyx Stent for Symptomatic Intracranial Stenosis: A Multicenter Propensity Score-Matched Comparison With Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial

BACKGROUND

Symptomatic intracranial atherosclerotic disease (sICAD) is estimated to cause 10% of strokes annually in the United States. However, treatment remains a challenge with several different stenting options studied in the past with unfavorable results.

OBJECTIVE

To report the 30-day stroke and/or death rate associated with intracranial stent placement for sICAD using Resolute Onyx Zotarolimus-Eluting Stent (RO-ZES) and provide a comparison with the results of Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial.

METHODS

Prospectively maintained databases across 8 stroke centers were used to identify adult patients treated with RO-ZES for sICAD between January 2019 and December 2021. Primary end point was composite of 30-day stroke, intracerebral hemorrhage, and/or death. Propensity score matching was performed using age, hypertension, lipid disorder, cigarette smoking, and symptomatic target vessel to create a matched group for comparison between RO-ZES and the SAMMPRIS medical management and treatment groups (SAMMPRIS percutaneous angioplasty and stenting [S-PTAS]).

RESULTS

A total of 132 patients met the inclusion criteria for analysis (mean age: 64.2 years). Mean severity of stenosis was 81.4% (±11.4%). A total of 4 (3.03%) stroke and/or deaths were reported within 30 days of treatment in the RO-ZES group compared with 6.6% in the SAMMPRIS medical management group (OR [odds ratio] 2.26, 95% CI 0.7-9.56, P = .22) and 15.6% in the S-PTAS group (OR 5.9, 95% CI 2.04-23.4, P < .001). Propensity score match analysis of 115 patients in each group demonstrated 30-day stroke and/or death rate of 2.6% in the RO-ZES group and 15.6% in the S-PTAS group (OR 6.88, 95% CI 1.92-37.54, P < .001).

CONCLUSION

Patients treated with RO-ZES had a relatively low 30-day stroke and/or death rate compared with the S-PTAS group. Further large-scale prospective studies are warranted to evaluate the safety and efficacy of RO-ZES for the treatment of sICAD.

Enhanced external counter pulsation therapy in patients with symptomatic and severe intracranial steno-occlusive disease: a randomized clinical trial protocol

Intracranial stenosis is prevalent among Asians and constitutes a common cause of cerebral ischemia. While the best medical therapy carries stroke recurrence rates in excess of 10% per year, trials with intracranial stenting have been associated with unacceptable peri-procedural ischemic events. Cerebral ischemic events are strongly related to the severity of intracranial stenosis, which is high in patients with severe intracranial stenosis with poor vasodilatory reserve. Enhanced External Counter Pulsation (EECP) therapy is known to improve myocardial perfusion by facilitating the development of collateral blood vessels in the heart. In this randomized clinical trial, we evaluate whether EECP therapy may be useful in patients with severe stenosis of intracranial internal carotid (ICA) or middle cerebral artery (MCA). The review of literature, methods of evaluation, status of currently used therapeutic approaches, and trial protocol have been presented.

Clinical trial registration

ClinicalTrials.gov, Identifier: NCT03921827.

A non-linear relationship between lesion length and risk of recurrent cerebral ischemia after stenting for symptomatic intracranial stenosis with hemodynamic impairment

Background

Stent placement can be an effective treatment for patients with symptomatic intracranial stenosis (sICAS) and hemodynamic impairment (HI). However, the association between lesion length and the risk of recurrent cerebral ischemia (RCI) after stenting remains controversial. Exploring this association can help predict patients at higher risk for RCI and develop individualized follow-up schedules.

Method

In this study, we provided a post-hoc analysis of a prospective, multicenter registry study on stenting for sICAS with HI in China. Demographics, vascular risk factors, clinical variables, lesions, and procedure-specific variables were recorded. RCI includes ischemic stroke and transient ischemic attack (TIA), from month 1 after stenting to the end of the follow-up period. Smoothing curve fitting and segmented Cox regression analysis were used to analyze the threshold effect between lesion length and RCI in the overall group and subgroups of the stent type.

Results

The non-linear relationship between lesion length and RCI was observed in the overall population and subgroups; however, the non-linear relationship differed by subgroup of stent type. In the balloon-expandable stent (BES) subgroup, the risk of RCI increased 2.17-fold and 3.17-fold for each 1-mm increase in the lesion length when the lesion length was <7.70 mm and >9.00 mm, respectively. In the self-expanding stent (SES) subgroup, the risk of RCI increased 1.83-fold for each 1-mm increase in the lesion length when the length was <9.00 mm. Nevertheless, the risk of RCI did not increase with the length when the lesion length was >9.00mm.

Conclusion

A non-linear relationship exists between lesion length and RCI after stenting for sICAS with HI. The lesion length increases the overall risk of RCI for BES and for SES when the length was <9.00 mm, while no significant relationship was found when the length was >9.00 mm for SES.

Editorial for "Pre-Surgical Magnetic Resonance Imaging Indicators of Revascularization Response in Adults With Moyamoya Vasculopathy"

Background:

Moyamoya is a progressive intracranial vasculopathy, primarily affecting distal segments of the internal carotid and middle cerebral arteries. Treatment may comprise angiogenesis-inducing surgical revascularization, however lack of randomized trials often results in subjective treatment decisions.

Hypothesis:

Compensatory pre-surgical posterior vertebrobasilar (VBA) flow-territory reactivity, including greater cerebrovascular reactivity and reduced vascular delay time, portends greater neoangiogenic response verified on digital subtraction angiography (DSA) at one-year follow-up.

Study Type:

Prospective intervention cohort.

Subjects:

31 patients with moyamoya (26 female; age=45±13 years; 41 revascularized hemispheres).

Methods:

Anatomical MRI, hypercapnic cerebrovascular reactivity MRI, and DSA acquired pre-surgically in adult moyamoya participants scheduled for clinically-indicated surgical revascularization. One year post-surgery, DSA was repeated to evaluate collateralization.

Field Strength:

3 Tesla.

Sequence:

Hypercapnic T 2*-weighted gradient-echo blood-oxygenation-level-dependent, T 2-weighted turbo-spin-echo fluid-attenuated-inversion-recovery, T 1-weighted magnetization-prepared-rapid-gradient-echo, and T 2-weighted diffusion-weighted imaging.

Assessment:

Pre-surgical maximum cerebrovascular reactivity and response times were evaluated in VBA flow-territories. Revascularization success was determined using an ordinal scoring system of neoangiogenic collateralization from post-surgical DSA by two cerebrovascular neurosurgeons (RVC; experience=8 years; MRF, experience=9 years) and one neuroradiologist (LTD, experience=8 years). Stroke risk factors (age, sex, race, vasculopathy, and diabetes) were recorded.

Statistical Tests:

Fisher’s exact and Wilcoxon rank-sum tests were applied to compare pre-surgical variables between cohorts with angiographically-confirmed good (>1/3 MCA territory revascularized) vs. poor (<1/3 MCA territory revascularized) outcomes. Significance: two-sided p<0.05. Normalized odds ratios (OR) were calculated.

Results:

Criteria for good collateralization were met in 25 of 41 revascularized hemispheres. Pre-surgical normalized VBA flow-territory cerebrovascular reactivity was significantly higher in those with good (1.12±0.13 unitless) vs. poor (1.04±0.05 unitless) outcomes. Younger (OR=−0.60±0.67) and White (OR=−1.81±1.40) participants had highest revascularization success (good outcomes: age=42±14 years, race=84% White; poor outcomes: age=49±11 years, race=44% White).

Data Conclusion:

Pre-surgical MRI-measures of VBA flow-territory cerebrovascular reactivity are highest in moyamoya participants with better angiographic responses to surgical revascularization.

Presurgical Magnetic Resonance Imaging Indicators of Revascularization Response in Adults With Moyamoya Vasculopathy

BACKGROUND

Moyamoya is a progressive intracranial vasculopathy, primarily affecting distal segments of the internal carotid and middle cerebral arteries. Treatment may comprise angiogenesis-inducing surgical revascularization; however, lack of randomized trials often results in subjective treatment decisions.

HYPOTHESIS

Compensatory presurgical posterior vertebrobasilar artery (VBA) flow-territory reactivity, including greater cerebrovascular reactivity (CVR) and reduced vascular delay time, portends greater neoangiogenic response verified on digital subtraction angiography (DSA) at 1-year follow-up.

STUDY TYPE

Prospective intervention cohort.

SUBJECTS

Thirty-one patients with moyamoya (26 females; age = 45 ± 13 years; 41 revascularized hemispheres).

METHODS

Anatomical MRI, hypercapnic CVR MRI, and DSA acquired presurgically in adult moyamoya participants scheduled for clinically indicated surgical revascularization. One-year postsurgery, DSA was repeated to evaluate collateralization.

FIELD STRENGTH

3 T.

SEQUENCE

Hypercapnic T 2 * -weighted gradient-echo blood-oxygenation-level-dependent, T2 -weighted turbo-spin-echo fluid-attenuated-inversion-recovery, T1 -weighted magnetization-prepared-rapid-gradient-echo, and T2 -weighted diffusion-weighted-imaging.

ASSESSMENT

Presurgical maximum CVR and response times were evaluated in VBA flow-territories. Revascularization success was determined using an ordinal scoring system of neoangiogenic collateralization from postsurgical DSA by two cerebrovascular neurosurgeons (R.V.C. with 8 years of experience; M.R.F. with 9 years of experience) and one neuroradiologist (L.T.D. with 8 years of experience). Stroke risk factors (age, sex, race, vasculopathy, and diabetes) were recorded.

STATISTICAL TESTS

Fisher's exact and Wilcoxon rank-sum tests were applied to compare presurgical variables between cohorts with angiographically confirmed good (>1/3 middle cerebral artery [MCA] territory revascularized) vs. poor (<1/3 MCA territory revascularized) outcomes.

SIGNIFICANCE

two-sided P < 0.05. Normalized odds ratios (ORs) were calculated.

RESULTS

Criteria for good collateralization were met in 25 of the 41 revascularized hemispheres. Presurgical normalized VBA flow-territory CVR was significantly higher in those with good (1.12 ± 0.13 unitless) vs. poor (1.04 ± 0.05 unitless) outcomes. Younger (OR = -0.60 ± 0.67) and White (OR = -1.81 ± 1.40) participants had highest revascularization success (good outcomes: age = 42 ± 14 years, race = 84% White; poor outcomes: age = 49 ± 11 years, race = 44% White).

DATA CONCLUSION

Presurgical MRI-measures of VBA flow-territory CVR are highest in moyamoya participants with better angiographic responses to surgical revascularization.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 4.

Dual anti-platelet therapy for secondary prevention in intracranial atherosclerotic disease: a network meta-analysis

Background:

Intracranial arterial stenosis (ICAS) is a non-marginal cause of stroke/transient ischemic attacks (TIAs) and is associated with high stroke recurrence rate. Some studies have investigated the best secondary prevention ranging from antithrombotic therapy to endovascular treatment (ET). However, no direct comparison between all the possible treatments is currently available especially between single and dual anti-platelet therapies (SAPT and DAPT).

Aim:

To establish whether DAPT is more effective than SAPT in preventing the recurrence of ICAS-related stroke, by means of a network meta-analysis (NMA).

Design:

Systematic review and NMA in accordance to PRISMA guidelines.

Data sources and methods:

We performed a systematic review of trials investigating secondary prevention (SAPT or DAPT, anticoagulant treatment or ET) in patients with symptomatic ICAS available in MEDLINE, Scopus and Web of Science from January 1989 to May 2021. We defined our primary efficacy outcome as the recurrence of ischemic stroke/TIA. We analysed the extracted data with Bayesian NMA approach.

Results:

We identified 815 studies and included 5 trials in the NMA. Sequence generation was adequate in all the selected studies while the allocation concealment method was described in one study. All the included studies reported the pre-specified primary outcomes, and outcome assessment was blinded in all the studies. We used the fixed-effect approach as the heterogeneity was not significant (p > 0.1) according to the Cochran’s Q statistic. DAPT was superior to SAPT and DAPT + ET in preventing stroke/TIA recurrence [respectively, odds ratio (OR), 0.59; confidence interval (CI), 0.39–0.9; and OR, 0.49, CI, 0.26–0.88], while no difference was found between DAPT and oral anticoagulant therapy (OAC). DAPT was safer than OAC (OR, 0.48; CI, 0.26–0.89) and DAPT + ET (OR, 0.50; CI, 0.35–0.71), while no difference was found between DAPT and SAPT.

Conclusion:

DAPT is more effective than SAPT for secondary stroke prevention in patients with symptomatic ICAS, without increasing the risk of haemorrhage.

Registration:

Prospero/CRD42019140033.

RNF213 R4810K Variant in Suspected Unilateral Moyamoya Disease Predicts Contralateral Progression

Background Early-stage unilateral moyamoya disease (MMD) is difficult to discriminate from isolated intracranial atherosclerotic stenosis, and identification of contralateral progression may aid in the diagnosis of MMD. The RNF213 (ring finger protein 213) R4810K variant is a strong genetic susceptibility factor for MMD; however, the role of contralateral progression in unilateral MMD is unknown. Methods and Results Patients who had undergone RNF213 R4810K genotyping with suspected unilateral MMD between January 2017 and August 2021 from 2 tertiary university hospitals were retrospectively reviewed. We compared the clinical features and radiographic outcomes of patients with and without this variant. The risk factors of contralateral progression in patients with suspected unilateral MMD were evaluated. The RNF213 R4810K variant was observed in 72 of 123 patients with suspected unilateral MMD, all of which were heterozygous. The allele frequency of the R4810K variant was significantly higher in the suspected unilateral MMD group compared with the historical control group (29.3% versus 1.2%; P<0.0001). Family history of MMD was significantly more common in patients with the variant than in those without (17% versus 4%; P=0.003). Eleven of 72 patients with the variant developed contralateral progression, whereas only 1 of 51 patients without the variant developed contralateral progression during a median follow-up period of 28 months (log-rank test; P=0.03). The presence of the RNF213 R4810K variant significantly correlated with contralateral progression (adjusted odds ratio, 6.39 [95% CI, 1.11-36.63]; P=0.04). Conclusions Contralateral progression is more likely to occur in patients with suspected unilateral MMD with the RNF213 R4810K variant than in those without the variant. However, because our study used a small sample size, this finding should be carefully interpreted and requires further studies with more patients and longer follow-up periods.

Pulsatile tinnitus due to stenosis of the supraclinoid segment of the internal carotid artery: Management with a low-profile self-expanding stent

Atherosclerotic stenosis of the internal carotid artery is a rare cause of pulsatile tinnitus. Stenosis responsible for tinnitus is usually located in the petrous segment of the vessel or, even more uncommonly, in the extracranial segment. However, to the best of our knowledge, a stenosis of the intradural supraclinoid segment of the internal carotid had never been reported as a source of pulsatile tinnitus. We describe the case of a man with a history of previous ischaemic stroke and invalidating pulsatile tinnitus, caused by a high grade, diaphragm-like shaped, stenosis of the supraclinoid internal carotid artery. The stenosis was treated with angioplasty and stenting with a low-profile self-expanding high radial force stent (Acclino flex HRF, Acandis). Tinnitus disappeared immediately after the procedure. At the two-year follow-up no recurrence of the tinnitus and the stenosis occurred. Intradural internal carotid artery stenosis should be considered as a very rare cause of pulsatile tinnitus.

Factors Influencing the Outcome of Symptomatic Intracranial Artery Stenosis With Hemodynamic Impairment After Short and Long-Term Stent Placement

Objective

Stent placement is a feasible approach worldwidely for patients with symptomatic intracranial artery stenosis (sICAS) and hemodynamic impairment (HI) who are at high risk of recurrent stroke after medical treatment. Exploration of factors associated with poor outcomes after stent placement could help develop better individualized therapeutic strategies.

Methods

This study conducted a post-hoc analysis of a prospective, multicenter registry study of stent use for sICAS with HI in China. Patient and clinical demographics, and stenotic lesion images were analyzed using univariate and multivariate Cox regression to the time until any endpoints or the end of the follow-up period. The short-term endpoint included any transient ischemic attack (TIA), stroke, or death within 1 month after stent placement. The long-term endpoints included the short-term endpoints and any TIA or stroke in the region of the affected artery that occurred more than 1 month after stent placement.

Results

Two hundred and ninety two patients were included, with 13 short-term and 39 long-term endpoints. Multivariate Cox regression analysis revealed that lesions at the arterial origin or bifurcation (Hazard Ratio (HR) = 7.52; 95% CI, 1.89-29.82; p = 0.004) were significantly associated with higher short-term risk. Baseline renal insufficiency reduced the risk (HR = 0.08; 95% CI: 0.01-0.68; p = 0.021). Factors significantly associated with higher long-term risk included irregular or ulcerated plaques at the lesion (HR = 2.15; 95% CI: 1.07-4.33; p = 0.031). Subgroup analyses indicated that higher risk occurred in the older age group (age>59 years, HR = 3.73, 95% CI: 1.27-10.97, p = 0.017), and not in the younger group (age≤59 years, HR = 1.12, 95% CI: 0.42-3.03, p = 0.822).

Conclusion

Irregular or ulcerated plaques in older patients and lesions at the arterial opening or bifurcation were more likely to result in adverse endpoints for stent placement during long or short -term follow-up. Investigation of these factors might facilitate the development of individualized therapeutic strategies for this population.

Clinical Trial Registration

http://www.clinicaltrials.gov, identifier: NCT01968122.

Transcarotid artery revascularization (TCAR) stenting or angioplasty for intracranial carotid artery stenosis: Case series and novel application

BACKGROUND

Carotid artery stenting is associated with a higher rate of stroke compared to carotid endarterectomy (CEA). This is likely due to procedural emboli resulting from plaque disruption. The transcarotid artery revascularization (TCAR) method aims to reduce the stroke rate by flow-reversal. TCAR, which has yet to be utilized for intracranial atherosclerotic disease (ICAD), may be particularly valuable given the lack of surgical treatment options for intracranial arterial stenosis.

OBJECTIVE

Presented here are five cases of angioplasty or stenting that demonstrate the feasibility of TCAR for intracranial Internal Carotid Artery (ICA) stenosis treatment.

METHODS

Five cases were reviewed retrospectively and summarized using PROCESS and CARE guidelines.

RESULTS

All patients who underwent intervention between the petrous and ophthalmic segment of the ICA had no new neurologic deficit nor detected embolic stroke. One patient experienced an asymptomatic 5 mm hemorrhage on postoperative routine Computed Tomography (CT) head imaging.

CONCLUSIONS

This highlights a new method for treating intracranial ICA stenosis with a potentially reduced stroke risk. Given the historically higher stroke rates for cervical ICA stenting compared to carotid artery endarterectomy, this method may improve the previously higher stroke rates in endovascular carotid artery treatment, compared to CEA. Although this series is small, it illustrates a novel use for a rising technique that should be further evaluated in a larger study to validate its efficacy as a new treatment modality for surgically inaccessible intracranial disease.

Effect of Ginkgolide in Ischemic Stroke patients with large Artery Atherosclerosis: Results from a randomized trial

BACKGROUND

Dual antiplatelet therapy is considered beneficial in acute ischemic stroke (AIS) patients with intracranial artery stenosis (ICAS), with more bleeding events. Ginkgolide is shown to reduce platelet activation after infarction, which might be of benefit in AIS. We aimed to explore the effect of Ginkgolide in AIS patients with ICAS.

METHODS

This was a randomized, double-blinded, placebo-controlled trial conducted at 61 centers in China. Within 72 h after onset, consecutive patients diagnosed as AIS with ICAS were randomized to either Ginkgolide or placebo treatment. The primary outcome was the composite of mortality and recurrent stroke (ischemic or hemorrhagic) during first 4 weeks in an intention-to-treat analysis. Secondary functional outcome was assessed by modified Rankin Scale and improvement of stroke severity was assessed by National Institution of Health Stroke Scale at day 28. Safety outcome was measured by the rate of severe adverse event (SAE).

RESULTS

There were 936 patients randomized to either Ginkgolide or placebo treatment. Their average age was 64.2 ± 10.4 years old and 36.0% of the patients were female. The composite index event occurred in six patients in placebo group, and none occurred in Ginkgolide group (risk ratio 1.01; 95% CI 1.00-1.02). There were more patients who achieved favorable outcome in Ginkgolide group, compared with that of the placebo group (OR 2.16, 95%CI 1.37-3.41). SAE occurred in five (1.1%) patients in the Ginkgolide group and three (0.6%) in the placebo group (OR0.60, 95CI% 0.14-2.53). Intracranial hemorrhage occurred in 1/473 (0.2%) in the placebo group.

CONCLUSIONS

Ginkgolide, working as PAF antagonist, may reduce recurrent stroke in AIS with ICAS patients within 72 hours after onset. It might be an optional treatment in moderate-to-severe AIS patients with ICAS. (http://www.chictr.org.cn Number as ChiCTR-IPR-17012310).

Cerebral hyperperfusion syndrome after intracranial stenting: Case report and systematic review

BACKGROUND

Cerebral Hyperperfusion Syndrome (CHS) is an uncommon complication observed after intracranial angioplasty or stenting procedures. Given to the increasing use of new devices for intracranial angioplasty and stenting (INCS), in selected patients with high ischemic stroke risk, an equally increasing knowledge of complications related to these procedures is mandatory.Case description: a 63-year-old man was diagnosed with an hyperperfusion syndrome after percutaneous angioplasty and stenting for severe symptomatic right internal carotid artery (ICA) siphon stenosis. After treatment he complained generalized seizures and respiratory failure. While conventional imaging did not demonstrate any acute brain lesions, Pseudo-Continuous Arterial Spin Labeling (PCASL) Perfusion MRI early documented right hemisphere blood flow increase suggestive for CHS.

CONCLUSIONS

Monitoring of perfusion changes after INCS could play an important a role in determining patients with high risk of CHS. ASL Perfusion MRI might be used for promptly, early diagnosis of CHS after treatment of severe intracranial artery stenosis.

Safety of endovascular therapy for symptomatic intracranial artery stenosis: a national prospective registry

INTRODUCTION

The safety outcomes of endovascular therapy for intracranial artery stenosis in a real-world stetting are largely unknown. The Clinical Registration Trial of Intracranial Stenting for Patients with Symptomatic Intracranial Artery Stenosis (CRTICAS) was a prospective, multicentre, real-world registry designed to assess these outcomes and the impact of centre experience.

METHODS

1140 severe, symptomatic intracranial arterial stenosis (ICAS) patients treated with endovascular therapy were included from 26 centres, further divided into three groups according to the annual centre volume of intracranial angioplasty and stent placement procedures over 2 years: (1) high volume for ≥25 cases/year; (2) moderate volume for 10-25 cases/year and (3) low volume for <10 cases/year.

RESULTS

The rate of 30-day stroke, transient ischaemic attack or death was 9.7% (111), with 5.4%, 21.1% and 9.7% in high-volume, moderate-volume and low-volume centres, respectively (p<0.05). Multivariable logistic regression confirmed high-volume centres had a significantly lower primary endpoint compared with moderate-volume centres (OR=0.187, 95% CI: 0.056 to 0.627; p≤0.0001), while moderate-volume and low-volume centres showed no significant difference (p=0.8456).

CONCLUSION

Compared with the preceding randomised controlled trials, this real-world, prospective, multicentre registry shows a lower complication rate of endovascular treatment for symptomatic ICAS. Non-uniform utilisation in endovascular technology, institutional experience and patient selection in different volumes of centres may have an impact on overall safety of this treatment.

Intraplaque Enhancement Is Associated With Artery-to-Artery Embolism in Symptomatic Vertebrobasilar Atherosclerotic Diseases

Objective: There are limited data regarding the characteristics of intracranial plaques according to stroke mechanism in the posterior circulation. This study aims to compare whether the plaque characteristics and baseline features are different in patients with artery-to-artery (A-to-A) embolism and those with parent artery disease in the intracranial vertebrobasilar atherosclerotic disease.

Methods: From September 2014 to January 2017, patients with recent posterior circulation stroke due to intracranial vertebrobasilar atherosclerotic disease were retrospectively analyzed. Patients with the following eligibility criteria were included: (1) age ≥18 years old, (2) ischemic stroke in the vertebrobasilar territory, (3) 70–99% stenosis of the intracranial vertebral artery or basilar artery, and (4) two or more atherosclerotic risk factors. Patients with concomitant ipsilateral or bilateral extracranial vertebral artery >50% stenosis, cardio-embolism, or non-atherosclerotic stenosis were excluded. The plaque characteristics, including intraplaque compositions (intraplaque hemorrhage and intraplaque calcification), intraplaque enhancement, and remodeling index, were evaluated by using 3T high-resolution magnetic resonance imaging (HRMRI). The baseline features including vascular risk factors and the involved artery were collected. Patients were divided into A-to-A embolism and parent artery disease groups based on the diffusion-weighted images, T2-weighted images, or computed tomography. The plaque characteristics and baseline features were compared between the two groups.

Results: Among consecutive 298 patients, 51 patients were included. Twenty-nine patients had A-to-A embolism and 22 patients had parent artery disease. Compared with parent artery disease, the occurrence rates of intraplaque enhancement and intracranial vertebral involvement were higher in the A-to-A embolism group (79.3 vs. 36.4%; p = 0.002 and 62.1 vs. 18.2%; p = 0.002, respectively). Multivariable logistic regression analysis showed that intraplaque enhancement and intracranial vertebral artery plaques were also associated with A-to-A embolism (adjusted OR, 7.31; 95% CI 1.58–33.77; p = 0.011 and adjusted OR, 9.42; 95% CI 1.91–46.50; p = 0.006, respectively).

Conclusion: Intraplaque enhancement and intracranial vertebral artery plaques seem to be more closely associated with A-to-A embolism than parent artery disease in patients with symptomatic intracranial vertebrobasilar disease.

Clinical Trial Registration:http://www.clinicaltrials.gov, identifier: NCT02705599.

A Prospective, Longitudinal Magnetic Resonance Imaging Evaluation of Cerebrovascular Reactivity and Infarct Development in Patients With Intracranial Stenosis

BACKGROUND

Patients with symptomatic atherosclerotic and non-atherosclerotic (i.e., moyamoya) intracranial steno-occlusive disease experience high 2-year infarct rates.

PURPOSE

To investigate whether cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) measures may provide biomarkers of 1-to-2-year infarct risk.

STUDY TYPE

Prospective, longitudinal study.

SUBJECTS

Adult participants (age = 18-85 years) with symptomatic intracranial atherosclerotic disease (N = 26) or non-atherosclerotic (i.e., moyamoya; N = 43) and stenosis ≥50% of a major intracranial artery were initially scanned within 45 days of stroke. Follow-up imaging (target  = 1.5 years) was acquired for new infarct assessment.

FIELD STRENGTH/SEQUENCE

3.0 Tesla with normocapnic arterial spin labeling (ASL) and blood oxygenation level-dependent (BOLD) imaging acquired during an interleaved hypercapnic (3 minutes) and normocapnic (3 minutes) respiratory stimulus.

ASSESSMENT

CBF, maximum CVR, and time-to-maximum CVR (i.e., CVR_DELAY ) were calculated. Laterality indices (difference between infarcted and contralesional hemispheres divided by sum of absolute values) of metrics at enrollment were contrasted between participants with vs. without new infarcts on follow-up.

STATISTICAL TESTS

Laterality indices were compared using non-parametric Wilcoxon tests (significance: two-sided P < 0.05) and effect sizes as Cohen's d. Continuous variables are presented as mean ± SD.

RESULTS

New infarcts were observed on follow-up in 15.0% of participants. The laterality index of the CVR_DELAY was elevated (P = 0.01) in participants with atherosclerosis with new infarcts (index = 0.13) compared to participants without new infarcts (index = 0.05).

DATA CONCLUSION

Elevated CVR_DELAY may indicate brain parenchyma at increased risk for new infarcts in patients with symptomatic intracranial atherosclerotic disease treated with standard-of-care medical management.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 3.

Cerebrovascular Contributions to Neurocognitive Disorders in People Living With HIV

BACKGROUND

To investigate a comprehensive array of magnetic resonance imaging (MRI)-based biomarkers of cerebrovascular disease (CVD) in a cohort of people living with HIV (PLWH) and relate these imaging biomarkers to cognition.

SETTINGS

Cross-sectional, community-based study.

METHODS

Participants were PLWH in New York City, aged 50 years or older. They underwent a brain magnetic resonance angiography or MRI to ascertain 7 MRI markers of CVD: silent brain infarcts, dilated perivascular spaces, microhemorrhages, white matter hyperintensity volume, white matter fractional anisotropy and mean diffusivity (measures of white matter integrity), and intracranial large artery stenosis. Participants underwent a battery of neurocognitive tests to obtain individual and global cognitive scores representative of various aspects of cognition.

RESULTS

We included 85 participants (mean age 60 ± 6 years, 48% men, 78% non-Hispanic Black), most of them with well-controlled HIV (75% with CD4 cell count > 200 cells/mm3 and viral load < 400 copies/mL at or near the time of the MRI scan). Silent brain infarcts, intracranial large artery stenosis, and poor white matter integrity were associated with poorer performance in at least one cognitive domain, but the sum of these 3 MRI markers of CVD was associated with lower working memory (B = -0.213, P = 0.028), list learning (B = -0.275, P = 0.019), and global cognition (B = -0.129, P = 0.007).

CONCLUSIONS

We identified silent brain infarcts, intracranial large artery stenosis, and poor white matter integrity as exposures that may be modifiable and may, therefore, influence cognitive decline. In addition, these MRI markers of CVD may help in identifying PLWH at higher risk of cognitive decline, which may be more amenable to targeted therapies.

Drug-Coated Balloons for the Treatment of Symptomatic Intracranial High-Grade Stenosis: A Review of the Current Rationale

Symptomatic intracranial atherosclerotic disease (sICAD) remains a challenging disorder in the neurovascular field. Despite best medical treatment, the recurrence rate for stroke remains high in patients with intracranial high-grade stenosis (>70–99%). Furthermore, two large randomized trials (SAMMPRIS and VISSIT) failed to prove the efficacy of percutaneous transluminal angioplasty and stenting in patients with sICAD. Drug-coated balloon percutaneous transluminal angioplasty (DCB-PTA) represents an alternative treatment modality with therapeutic benefits for interventional cardiology. However, there are very few articles in the existing literature that relate to the use of DCB-PTA in sICAD patients. Here, we aimed to review the rationale underlying the use of DCB-PTA in sICAD patients and summarize recent developments in the neurovascular field.

Risk factors associated with recurrence of ischemic stroke after intracranial stenting in china: a case-control study

Objectives: To investigate the factors affecting the risk of recurrent stroke after intracranial artery stenting.Methods: This is a subgroup analysis of a prospective single-arm registry study with 20 participating sites. Patients aged 18-85 years old with symptomatic intracranial atherosclerotic stenosis caused by 70-99% stenosis combined with poor collaterals were included in this study. The median follow-up in this study was 26.4 months.Results: A total of 260 patients were recruited in this study. Ischemic stroke related to target vessel occurred in 11 patients (4.2%) from 30 days to the last follow-up. The multivariate analysis revealed age ≥60 years old (OR: 11.991, 95% CI: 1.400-102.716; p = 0.023), no smoking (OR: 0.087, 95% CI: 0.010-0.787; p = 0.030), and Mori C type (OR: 5.129, 95% CI: 1.242-21.178; p = 0.024) retained significance in the model. There was no significant difference in the ischemic stroke based on medical history of hypertension, diabetes, dyslipidemia, baseline percent stenosis, length of stenosis, residual stenosis, and different stent types.Conclusions: Recurrence of ischemic stroke after intracranial stenting may be associated with elderly age, non-smoking, and Mori C type lesion. These factors will need to be monitored in future trials of intracranial stenting.Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01968122.

Frequency-Domain Optical Coherence Tomography for Intracranial Atherosclerotic Stenosis: Feasibility, Safety, and Preliminary Experience

Background: Despite advances in non-invasive imaging, the characterization of atherosclerotic plaque remains superior with frequency-domain optical coherence tomography (FD-OCT) in the clinical coronary and experimental cerebrovascular literature. An assessment of the feasibility and safety of FD-OCT for intracranial atherosclerotic stenosis (ICAS) is desirable. Methods: We analyzed a cohort of all consecutive FD-OCT evaluations for ICAS performed at our institution from April 2017 to August 2018 (16 months) in patients who suffered from transient ischemic attack (TIA) or non-disabling stroke despite optimal medical management within 90 days of admission attributable to angiographically verified 70-99% stenosis of an intracranial artery. Results: Thirty-three patients harboring 36 lesions with an average age of (57.6 ± 7.1) years (male sex 27 cases) comprising nine cases of lesions located within the anterior circulation and 24 cases within the posterior circulation were identified. Of the 33 patients with 36 lesions, the FD-OCT imaging catheter detected 35/36 (97%) lesions except in one case in which the FD-OCT catheter failed to navigate excessively tortuous vessels, and FD-OCT images in 27 patients (81.8%) were finally obtained successful, where the target lesion was fully visible, and image quality under at least one pullback was graded 2 or 3. There were no symptomatic complications. Blood flow was the most common artifact encountered (51.9%). Conclusion: FD-OCT is safe and feasible for the assessment of ICAS in the anterior and posterior circulation. The use of diagnostic interferometry will have to be weighed against its cost, and these preliminary findings should be verified by prospective large-scale studies.

Intracranial Atherosclerotic Stenosis is Related to Post-stroke Cognitive Impairment: A Cross-sectional Study of Minor Stroke

BACKGROUND

Intracranial Atherosclerotic Stenosis (ICAS) is an important risk factor for cognitive impairment. However, it is unclear whether patients with ICAS are more likely to develop cognitive impairment after an acute, non-disabling ischemic stroke (minor stroke).

OBJECTIVE

We aimed to investigate the association between ICAS and post-stroke cognitive impairment.

METHODS

In this cross-sectional study, patients with acute, non-disabling ischemic stroke underwent two cognitive tests and imaging evaluation for ICAS, within two weeks after the stroke. To determine the association between ICAS and post-stroke cognitive impairment, we performed a multivariate logistic regression analysis adjusted for several demographic and vascular risk factors.

RESULTS

Of the 164 patients with minor stroke in this study, 98 (59.76%) were diagnosed with poststroke cognitive impairment (Montreal Cognitive Assessment score<26). After adjusting for potential confounders, we found that patients with ICAS were more likely to develop cognitive impairment after an acute, non-disabling ischemic stroke, compared to patients without ICAS (Odds Ratio: 2.13; 95% Confidence Interval: 1.07-4.26), and underperformed in the tests of visuospatial and executive function.

CONCLUSION

In this cross-sectional study of a population that has experienced a minor stroke, our findings demonstrated a positive association between ICAS and post-stroke cognitive impairment.

MRI Markers of Mixed Pathology and Cognitive Impairment in Multiethnic Asians

There is a need to elucidate the combined influence of neurodegeneration and cerebrovascular disease (CeVD) on cognitive impairment, especially in diverse populations. Here, we evaluated 840 multiethnic individuals (mean age = 70.18) across the disease spectrum from the Epidemiology of Dementia in Singapore study. First, we determined whether a validated quantitative MRI score of mixed pathology is associated with clinical diagnosis and whether the score differed between ethnicities (Chinese, Malays, and Indians). We then evaluated whether the score was associated with multidomain cognitive impairment and if additional measures of CeVD were further associated with cognitive impairment. We found that lower quantitative MRI scores were associated with severity of clinical diagnosis and Chinese individuals had the highest quantitative MRI scores, followed by Indians and Malays. Lower quantitative MRI scores were also associated with lower performance in attention, language, visuoconstruction, visuomotor, visual, and verbal memory domains. Lastly, the presence of intracranial stenosis and cortical cerebral microinfarcts, but not cerebral microbleeds, were associated with memory performance beyond quantitative MRI scores. Taken together, our results demonstrate the utility of using multiple MRI markers of neurodegeneration and CeVD for identifying multiethnic Asians with the greatest cognitive impairment due to mixed pathology.

Evolving ischemic stroke subtypes in 15 years: A hospital-based observational study

BACKGROUND

Depicting the time trends of ischemic stroke subtypes may inform healthcare resource allocation on etiology-based stroke prevention and treatment.

AIM

To reveal the evolving ischemic stroke subtypes from 2004 to 2018.

METHODS

We determined the stroke etiologies of consecutive first-ever transient ischemic attack or ischemic stroke patients admitted to a regional hospital in Hong Kong from 2004 to 2018. We analyzed the age-standardized incidences and the two-year recurrence rate of major ischemic stroke subtypes.

RESULTS

Among 6940 patients admitted from 2004 to 2018, age-standardized incidence of ischemic stroke declined from 187.0 to 127.4 per 100,000 population (p < 0.001), driven by the decrease in large artery disease (43.0-9.67 per 100,000 population (p < 0.001)), and small vessel disease (71.9-45.7 per 100,000 population (p < 0.001)). Age-standardized incidence of cardioembolic stroke did not change significantly (p = 0.2). Proportion of cardioembolic stroke increased from 20.4% in 2004-2006 to 29.3% in 2016-2018 (p < 0.001). Two-year recurrence rate of intracranial atherothrombotic stroke reduced from 19.3% to 5.1% (p < 0.001) with increased prescriptions of statin (p < 0.001) and dual antiplatelet therapy (p < 0.001). In parallel with increased anticoagulation use across the study period (p < 0.001), the two-year recurrence of AF-related stroke reduced from 18.9% to 6% (p < 0.001).

CONCLUSION

Etiology-based risk factor control might have led to the diminishing stroke incidences related to atherosclerosis. To tackle the surge of AF-related strokes, arrhythmia screening, anticoagulation usage, and mechanical thrombectomy service should be reinforced. Comparable preventive strategies might alleviate the enormous stroke burden in mainland China.

Association of Type 2 Diabetes Mellitus and Glycemic Control With Intracranial Plaque Characteristics in Patients With Acute Ischemic Stroke

BACKGROUND

Type 2 diabetes mellitus (T2DM) has shown to be associated with carotid plaque vulnerability. However, the impact of T2DM on intracranial artery atherosclerosis is not well-understood.

PURPOSE

To evaluate the association of diabetes and glycemic control with intracranial atherosclerotic plaque characteristics identified by three-dimensional contrast enhanced MR vessel wall imaging in patients after acute ischemic stroke.

STUDY TYPE

Prospective.

POPULATION

Two hundred and eighty-eight symptomatic patients with acute ischemic stroke due to intracranial atherosclerotic plaque.

FIELD STRENGTH/SEQUENCE

T₁ WI volume isotropic turbo spin-echo acquisition sequence at 3.0 T.

ASSESSMENT

Clinical profiles, blood biomarkers, the number of intracranial plaques, plaque enhanced score, and the features (location, luminal stenotic rate, intraplaque hemorrhage, length, burden, enhancement grade, and ratio) of culprit plaque (defined as the most stenotic lesion ipsilateral to the ischemic event) and nonculprit plaque were analyzed by three radiologists.

STATISTICAL TESTS

Analysis of variance (ANOVA), Shapiro-Wilk normality test, Levene's test, ANOVA with Bonferroni post-hoc test, Kruskal Wallis H test with subsequent pairwise comparisons, chi-square with Bonferroni post-hoc test, generalized linear regression, Pearson correlation test, Kendall's W and intra-class correlation coefficient.

RESULTS

Two hundred and twenty-five participants (age 60 ± 10 years, 58.7% male) with 958 intracranial plaques were included. More intracranial plaques were found in the T2DM group than the non-T2DM group (4.80 ± 2.22 vs. 3.60 ± 1.78, P < 0.05). Patients with poorly-controlled T2DM exhibited higher culprit plaque enhancement ratio than patients with well-controlled T2DM and non-T2DM (2.32 ± 0.61 vs. 1.60 ± 0.62 and 1.39 ± 0.39; respectively, P < 0.05). After adjusting for other clinical variables, T2DM was independently associated with increased intracranial plaque number (β = 0.269, P < 0.05), and HbA1c level was independently associated with culprit plaque enhancement ratio (β = 0.641, P < 0.05) in multivariate analysis.

DATA CONCLUSION

T2DM is associated with an increased intracranial plaque number. Higher HbA1c is associated with stronger plaque enhancement. 3D contrast enhanced MR vessel wall imaging may help better understand the association of T2DM and glycemic control with intracranial plaque.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 3.

The effect of intracranial stenosis on cognitive decline in a memory clinic cohort

BACKGROUND AND PURPOSE

Intracranial stenosis (ICS) is a risk factor for cognitive impairment and dementia in cross-sectional studies. However, data examining the effect of ICS on cognitive decline are limited. We investigated the effect of ICS on cognition over a period of 3 years in a memory clinic cohort.

METHODS

Patients were recruited from the National University Hospital in Singapore. Data were collected using a standardised questionnaire, physical examination, and 3-T magnetic resonance imaging (MRI) at baseline. ICS was defined as arterial narrowing that exceeded 50% of the luminal diameter in any intracranial vessel. Cognition was measured at baseline and annually for 3 years using the Mini-Mental State Examination, the Montreal Cognitive Assessment, and a detailed neuropsychological test battery. The association between ICS and cognitive decline was analysed using generalised estimating equations.

RESULTS

A total of 364 patients were included in the analysis. The mean (±SD) age was 71.9 (±8.0) years, and 164 (45.1%) patients were male. A total of 66 (18.1%) patients had ICS. ICS was associated with worse executive function (β = -0.37, 95% confidence interval = -0.68 to -0.05, p = 0.022) and modified the effect of follow-up time on memory (p = 0.005) and visuomotor speed (p = 0.047). These results remained significant after controlling for demographics, overall diagnosis, cardiovascular risk factors, and MRI markers of cerebrovascular disease.

CONCLUSIONS

Intracranial stenosis was independently associated with worse executive function across all time points, and cognitive decline in memory and visuomotor speed over 3 years of follow-up. This suggests that ICS may be a useful indicator of vascular brain damage leading to cognitive decline and may warrant consideration of antiatherosclerotic treatment in clinical trials.

Feasibility and safety of the strategy of first stenting without retrieval using Solitaire FR as a treatment for emergent large-vessel occlusion due to underlying intracranial atherosclerosis

OBJECTIVE

The optimal treatment for underlying intracranial atherosclerosis (ICAS) in patients with emergent large-vessel occlusion (ELVO) remains unclear. Reocclusion during endovascular treatment (EVT) occurs frequently (57.1%-77.3%) after initial recanalization with stent retriever (SR) thrombectomy in ICAS-related ELVO. This study aimed to compare treatment outcomes of the strategy of first stenting without retrieval (FRESH) using the Solitaire FR versus SR thrombectomy in patients with ICAS-related ELVO.

METHODS

The authors retrospectively reviewed consecutive patients with acute ischemic stroke and intracranial ELVO of the anterior circulation who underwent EVT between January 2017 and December 2019 at Yeungnam University Medical Center. Large-vessel occlusion (LVO) of the anterior circulation was classified by etiology as follows: 1) no significant stenosis after recanalization (embolic group) and 2) remnant stenosis > 70% or lesser degree of stenosis with a tendency toward reocclusion and/or flow impairment during EVT (ICAS group). The ICAS group was divided into the SR thrombectomy group (SR thrombectomy) and the FRESH group.

RESULTS

A total of 105 patients (62 men and 43 women; median age 71 years, IQR 62.5-79 years) were included. The embolic, SR thrombectomy, and FRESH groups comprised 66 (62.9%), 26 (24.7%), and 13 (12.4%) patients, respectively. There were no significant differences between the SR thrombectomy and FRESH groups in symptom onset-to-door time, but puncture-to-recanalization time was significantly shorter in the latter group (39 vs 54 minutes, p = 0.032). There were fewer stent retrieval passes but more first-pass recanalizations in the FRESH group (p < 0.001). Favorable functional outcomes were significantly more frequent in the FRESH group (84.6% vs 42.3%, p = 0.017).

CONCLUSIONS

This study's findings suggest that FRESH, rather than rescue stenting, could be a treatment option for ICAS-related ELVO.

Platelet-Derived Growth Factor Is Associated with Progression of Symptomatic Intracranial Atherosclerotic Stenosis

BACKGROUND AND PURPOSE

We aimed to determine the relationships of 33 biomarkers of inflammation, oxidation, and adipokines with the risk of progression of symptomatic intracranial atherosclerotic stenosis (ICAS).

METHODS

Fifty-two of 409 patients who participated in the TOSS-2 (Trial of Cilostazol in Symptomatic Intracranial Stenosis-2) showed progression of symptomatic ICAS in magnetic resonance angiography at 7 months after an index stroke. We randomly selected 20 patients with progression as well as 40 age- and sex-matched control patients. We serially collected blood samples at baseline, 1 month, and 7 months after an index stroke. Multiplex analysis of biomarkers was then performed.

RESULTS

Demographic features and risk factors such as hypertension, diabetes, and smoking history were comparable between the two groups. Univariate analyses revealed that the levels of platelet-derived growth factor (PDGF)-AA [median (interquartile range)=1.64 (0.76-4.57) vs. 0.77 (0.51-1.71) ng/mL], PDGF-AB/BB [10.31 (2.60-25.90) vs. 2.35 (0.74-6.70) ng/mL], and myeloperoxidase [10.5 (7.5-22.3) vs. 7.8 (5.5-12.2) ng/mL] at 7 months were higher in the progression group. In the multivariate analysis using logistic regression, the PDGF AB/BB level at 7 months was independently associated with the progression of ICAS (p=0.02).

CONCLUSIONS

The PDGF-AB/BB level is associated with the progression of ICAS, and so may play a significant role in the progression of human ICAS.

The Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis Trial: Reanalysis Using the FDA "On Label" Criteria

BACKGROUND AND PURPOSE

Due to higher rates of 1-month stroke and death with Wingspan intracranial stent placement observed in SAMMPRIS, the Food and Drug Administration (FDA) announced a more limited indication for Wingspan stent.

METHODS

We compared the results of intracranial stent placement with best medical treatment in patients recruited in SAMMPRIS who met the new "on label" criteria with those who were categorized as "off label." The primary endpoint was any stroke or death occurring within 30 days of enrollment, or an ischemic stroke in the territory of the symptomatic intracranial artery from day 31 after study entry to completion of follow-up.

RESULTS

A total of 31 (7%) among 451 recruited patients met the "on label" criteria. The relative risk of primary endpoint was lower in "on label" patients treated with stent placement compared with best medical treatment (relative risk .61, 95% confidence interval .2-1.7) but higher in "off label" patients (relative risk 1.81, 95% confidence interval 1.2-2.6). Primary endpoint was seen in 20% and 23.4% of patients treated with stent placement in "on label" and "off label" patients, respectively. Primary endpoint was seen in 25% and 14.2% of patients treated with best medical treatment in "on label" and "off label" patients, respectively.

CONCLUSION

The new FDA "on label" criteria may identify a small group of people, who may benefit from intracranial stent placement due to higher risk of primary endpoint in those treated with best medical treatment.

Endovascular Therapy for Intracranial Artery Stenosis: Results from the Japanese Registry of Neuroendovascular Therapy (JR-NET)3

A total of 907 patients enrolled in the Japanese Registry of Neuroendovascular Therapy (JR-NET)3, a surveillance study in Japan, who underwent intracranial percutaneous transluminal angioplasty (PTA)/stenting for intracranial stenosis during the period from 2010 to 2014 were investigated. Technical success was achieved in 97.5% of the patients, and 6.8% had a residual stenosis of ≥50%. The incidence rates of ischemic and hemorrhagic complications were as low as 5.3% and 3.1%, respectively, and the mortality rate was 1.9%. However, the mortality rate of cases with either complications was higher at 10.7%. About half of the treatment cases were performed between 24 h and 14 days after onset, and the incidence of perioperative complications was similar to that after at least 15 days. Although it is necessary to verify the effectiveness of PTA/stenting within 14 days, the results of this treatment were stable regardless of the intervention period.

Tandem Short-length Multi-stent Construct for Emergent Revascularization of Occlusive Long-segment Left Middle Cerebral Artery In-stent Stenosis

Endovascular stenting and balloon angioplasty is a feasible although controversial option for intracranial atherosclerotic stenosis refractory to maximize medical management. High rates of symptomatic in-stent restenosis (ISR) have been identified with Wingspan stent (Stryker, Fremont, CA, USA) placement. Revascularization of ISR by way of re-stenting is often attempted, albeit with high risk and low durability. In lesions with long-segment non-focal critical or emergent occluded stenosis, re-stenting with a single balloon mounted stent is not possible due to deliverability of a lengthy device through a tortuous carotid siphon. Tandem drug-eluting stent placement within the middle cerebral artery to address acute, occlusive ISR using a Wingspan stent, with additional stent reconstruction, has not been previously described.

Emergency Intracranial Stenting in Acute Stroke: Predictors for Poor Outcome and for Complications

Background

Stent‐retriever thrombectomy is the first‐line therapy in acute stroke with intracranial large vessel occlusion. In case of failure of stent‐retriever thrombectomy, rescue stent angioplasty might be the only treatment option to achieve permanent recanalization. This study aims at identifying predictors for poor outcome and complications in a large, multicenter cohort receiving rescue stent angioplasty.

Methods and Results

We performed a retrospective analysis of patients with large vessel occlusion who were treated with rescue stent angioplasty after stent‐retriever thrombectomy between 2012 and 2018 in 7 neurovascular centers. We defined 2 binary outcomes: (1) functional clinical outcome (good modified Rankin Scale, 0–2; and poor modified Rankin Scale, 4–6) and (2) early symptomatic intracerebral hemorrhage. Impacts of clinical, radiological, and interventional parameters on outcomewere assessed in uni‐ and multivariable logistic regression models. Two hundred ten patients were included with target vessels located within the anterior circulation (136 of 210; 64.8%) and posterior circulation (74 of 210; 35.2%). Symptomatic intracerebral hemorrhage occured in 22 patients, 86.4% (19 of 22) after anterior and 13.6% (3 of 22) after posterior circulation large vessel occlusion. Good functional outcome was observed in 44.8% (73 of 163). A higher National Institutes of Health Stroke Scale on admission (adjusted odds ratio, 1.10; P=0.002), a higher premorbid modified Rankin Scale (adjusted odds ratio, 2.02; P=0.049), and a modified Thrombolysis in Cerebral Infarction score of 0 to 2a after stenting (adjusted odds ratio, 23.24; P<0.001) were independent predictors of poor functional outcome.

Conclusions

Use of rescue stent angioplasty can be considered for acute intracranial large vessel occlusion in cases after unsuccessful stent‐retriever thrombectomy. Likelihood of symptomatic intracerebral hemorrhage is higher in anterior circulation stroke.

Hyperhomocysteinemia Causes Severe Intraoperative Thrombotic Tendency in Superficial Temporal Artery-middle Cerebral Artery Bypass

CASE

Two years ago, annual magnetic resonance imaging for unruptured right internal carotid artery aneurysm of a 47-year-old woman detected a cerebral infarct in her right occipital lobe which was unknown etiology and antiplatelet therapy was initiated. She presented with sensory disorder of her left fingers 4 months ago. Infarction in right parieto-occipital cortex and severe stenosis of right middle cerebral artery was revealed. Her laboratory test was normal except remarkably high homocysteine value. Regardless of dual anti-platelet therapy, she suffered from repeated minor stroke and the stenosis was progressing. Therefore, right superficial temporal artery - middle cerebral artery bypass was undertaken. Aspirin and clopidogrel were withdrawn 1 week before the surgery. Two branches were anastomosed with 2 separate frontal M4 branches. Although patency was confirmed immediately after the anastomosis, thrombus formation was revealed after 10 minutes. We needed to perform removal of the thrombus and re-anastomosis twice. Intraoperative administration of aspirin and ozagrel alleviated thrombotic tendency. After surgery, antiplatelet therapy and supplementation with folate and vitamin B were performed. Her postoperative course was uneventful and patency of both anastomoses was confirmed.

DISCUSSION

Controversy still exists regarding preoperative antiplatelet therapy before superficial temporal artery-middle cerebral artery bypass, and folates and B6-12 vitamins supplementation for hyperhomocysteinemia. Considering intraoperative thrombo tendency in our case, it is recommended to evaluate the homocysteine level before bypass surgery for intracranial stenosis especially for young patients or patients with unknown etiology. Before bypass surgery of the patient with hyperhomocysteinemia, continuation of perioperative antiplatelet drugs and supplementation with folates and B6-12 vitamins are mandatory.

Intracranial Stenting After Failed Thrombectomy in Patients With Moderately Severe Stroke: A Multicenter Cohort Study

Background and Purpose: Recently, acute intracranial stenting (ICS) has gained more interest as a potential bailout strategy for large vessel occlusions (LVO) that are refractory to thrombectomy. However, there are currently no reports on ICS in patients with moderately severe stroke discussing the question if implementing a permanent stent is feasible and leads to improved recanalization after failed thrombectomy. Methods: We analyzed a large multicenter database of patients receiving ICS for anterior circulation LVO after failed thrombectomy. Inclusion criteria were defined as: Moderately severe stroke (National Institute Health Stroke Scale (NIHSS) ≤9 on admission), anterior circulation LVO, acute ICS after failed stent retriever MT. Primary endpoint was the rate of improved successful recanalization after ICS defined as a modified Thrombolysis In cerebral Infarction (mTICI) score≥2b. Favorable neurological outcome was defined as an early neurological improvement (ENI) of 4 points or reaching 0 with respect to baseline NIHSS. Results: Forty-one patients met the inclusion criteria. A median of 2 retrievals were performed (IQR 1-4) prior decision-making for ICS. ICS led in 90.2% (37/41) of cases to a final mTICI≥2b with significant improvement (p < 0.001) after the last retrieval attempt. The median NIHSS decreased (p = 0.178) from 7 (IQR 3.5-8) on admission to 2.5 (IQR 0-8.25) at discharge. ENI was observed in 47.4% (18/38). sICH occurred in 4.8% (2/41). Conclusion: ICS after failed thrombectomy appears to effectively improve recanalization rates in patients with moderately severe strokes. Thus, ICS should be considered also for patients with baseline NIHSS ≤9 if thrombectomy fails.

3.0 Tesla magnetic resonance angiography for detection of intracranial stenosis of the internal carotid artery: A prospective cohort study

Hemodynamic changes may provide important information for clinical decision-making in internal carotid artery (ICA) stenosis. The degree of stenosis is responsible for the hemodynamic changes. For detection of intracranial stenosis, each diagnostic method has its own advantages and disadvantages. The goal of the present study was to compare the sensitivity and accuracy of color-coded duplex sonography with that of magnetic resonance angiography (MRA) for the detection of intracranial stenosis. Patients with 3 vessels and/or left stem coronary artery disease were subjected to transcranial and extracranial color-coded duplex sonography (n=998), MRA (n=998) and invasive catheter angiography (n=939). The degree of stenosis was defined according to the Warfarin-Aspirin Symptomatic Intracranial Disease methodology. A ≥50% reduction in artery diameter was considered as a positive obstructive lesion. The benefits of each imaging method were assessed by clinical decision-making analysis. Color-coded duplex sonography and MRA, had sensitivities of 0.935 and 0.957 and accuracies of 0.92 and 0.974, respectively, when using invasive catheter angiography as a gold standard. The number of false-positive obstructive lesions detected by MRA was significantly higher than that for color-coded duplex sonography (53 vs. 13, P<0.0001). Color-coded duplex sonography was able to detect an obstructive lesion in one single image for ICAs with ≥57% stenosis, while MRA was only capable of detecting an obstructive lesion in one single image for ICAs with ≥80% stenosis. In conclusion, color-coded duplex sonography is a reliable method for the detection of intracranial stenosis in patients with coronary artery disease.

Cerebral blood flow territory instability in patients with atherosclerotic intracranial stenosis

BACKGROUND

Stroke risk stratification in patients with symptomatic intracranial atherosclerotic arterial disease (ICAD) remains an important clinical objective owing to the high 14-19% recurrent stroke rate in these patients on standard-of-care medical management. There thus remains a need for hemodynamic markers that may allow for the selection of personalized therapies for high-risk symptomatic patients.

PURPOSE

To determine if shifting of cerebral blood flow (CBF) territories in response to changes in cerebral perfusion pressure (CPP) may provide a marker for stroke risk in ICAD patients.

STUDY TYPE

Prospective.

POPULATION

Twenty ICAD patients who experienced a stroke within 45 days of study enrollment and 10 healthy controls.

SEQUENCE

3.0T MRI including anatomical imaging (T1 -weighted, T2 -weighted/FLAIR), 3D MR angiography, and normocapnic and hypercapnic vessel-encoded CBF-weighted arterial spin labeling.

ASSESSMENT

Patients were scanned within 45 days of overt stroke and monitored (duration = 13.2 ± 4.4 months) for the endpoint of non-cardioembolic stroke or transient ischemic attack. Flow territory shifting (shifting index) was calculated from the first scan by determining whether a voxel shifted from its primary arterial source from normocapnia to hypercapnia.

STATISTICAL TESTS

A Mann-Whitney U-test (significance: P < 0.05) was performed to determine whether patients meeting the endpoint had greater shifting indices relative to controls or patients not meeting the endpoint.

RESULTS

Shifting indices (mean ± standard error) were significantly higher in patients meeting endpoint criteria relative to controls (P = 0.0057; adjusted P = 0.036) and patients not meeting endpoint criteria (P = 0.0047; adjusted P = 0.036).

DATA CONCLUSION

Flow territory shifting may provide a marker of recurrent stroke risk in symptomatic ICAD patients on standard-of-care medical management therapies.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1441-1451.

Ring Finger Protein 213 Variant and Plaque Characteristics, Vascular Remodeling, and Hemodynamics in Patients With Intracranial Atherosclerotic Stroke: A High-Resolution Magnetic Resonance Imaging and Hemodynamic Study

Background

Intracranial atherosclerotic stroke is prevalent in Asians. We hypothesized that patients with the ring finger protein 213 (RNF213) variant, a susceptibility locus for moyamoya disease in Asians, have different neuroimaging characteristics in terms of the vessel wall and hemodynamics.

Methods and Results

We analyzed consecutive patients with ischemic events in middle cerebral artery distribution and relevant plaques of the distal internal carotid artery or proximal middle cerebral artery on high‐resolution magnetic resonance imaging. Patients with carotid/cardiac sources of embolism or moyamoya disease were excluded. High‐resolution magnetic resonance imaging features (eg, outer vessel diameters and plaque characteristics) and fractional flow (as measured by adjusted signal intensity ratio on time‐of‐flight magnetic resonance angiography) were compared between RNF213 p.Arg4810Lys variant carriers and noncarriers. Among 144 patients included, 44 (29.9%) had the RNF213 variant. Clinical characteristics, including age, sex, body mass index, and vascular risk factors, were not significantly different between RNF213 variant carriers and noncarriers. However, the outer vessel diameter was smaller in RNF213 variant carriers than in noncarriers (P<0.0001 for middle cerebral artery of relevant stenosis [2.05‐mm analysis of RNF213 gene for moyamoya disease in the Chinese HAN population 2.75 mm]; P<0.0001 for contralateral side [2.42  versus 3.00 mm] and P<0.001 for basilar artery [3.19 versus 3.53 mm]). Other high‐resolution magnetic resonance imaging features, including plaque morphology and eccentricity, were not significantly different. Fractional flow was diminished in patients with smaller‐diameter intracranial arteries with a similar degree of stenosis.

Conclusions

The RNF213 variant may be associated with vasculogenesis, but not with atherogenesis. Patients with this variant had small intracranial arteries predisposing hemodynamic compromise in the presence of intracranial atherosclerosis. In addition to antiatherosclerotic strategies, further studies are warranted to develop novel therapeutic strategies against RNF213 vasculopathy in Asians.

See Editorial Liu and Gutierrez

Neuroform EZ Stenting for Symptomatic Intracranial Artery Stenosis: 30 Days Outcomes in a High-Volume Stroke Center

Objective: To test whether Neuroform EZ stent placement combined with the modified techniques in symptomatic severe intracranial stenosis (ICAS) would result in lower rates of peri-procedural complications of intracranial stenting. Methods: We retrospectively reviewed the clinical data from 71 consecutive patients who underwent Neuroform EZ stent placement combined with the modified techniques for symptomatic severe ICAS at our institute between January 2016 and October 2017. The primary outcomes were ipsi-lateral ischemic stroke, intra-cerebral hemorrhage, or death within 30 days after stenting. The secondary outcome was technical success. Results: The technical success rate was 100%. The mean pre and post-stent stenoses were 84.2% ± 9.1% (median 85%, IQR75% to 90%) and 16.9% ± 10.2 % (median 15%, IQR 10% to 25%). The frequency of ipsi-lateral stroke, intra-cerebral hemorrhage, or death within 30 days was 0%. Conclusions: The combined use of Neuroform EZ stent placement and the modified techniques for symptomatic severe ICAS is technically feasible and safe, with very low peri-procedural complications. Further studies are required to assess the long-term results of this approach.

What Threshold Defines Penumbral Brain Tissue in Patients with Symptomatic Anterior Circulation Intracranial Stenosis: An Exploratory Analysis

BACKGROUND AND PURPOSE

Impaired distal perfusion predicts neurological deterioration in large artery atherosclerosis. We aim to determine the optimal threshold of Tmax delay on perfusion imaging that is associated with neurological deterioration in patients with symptomatic proximal anterior circulation large artery stenosis.

METHODS

Data were abstracted from a prospective ischemic stroke database of consecutively enrolled patients with symptomatic proximal intracranial stenosis (internal carotid artery or M1 segment of the middle cerebral artery) who underwent magnetic resonance perfusion imaging within 24 hours of symptom onset during a 15-month period. Tissue volumes of perfusion delay Tmax 0-4 seconds, Tmax > 4 seconds, Tmax > 6 seconds, and Tmax > 8 seconds were calculated using an automated approach. A target mismatch (penumbra-core) was defined as ≥15mL of brain tissue using each of the Tmax threshold categories. The outcome was neurological deterioration at 30 days defined as new or worsening neurological deficits that are not attributed to a nonvascular etiology.

RESULTS

Among 52 patients with symptomatic intracranial stenosis, 26 patients met inclusion criteria. Neurological deterioration was associated with target mismatch profile defined according to Tmax > 6 seconds (66.7% [6/9] vs. 5.9% [1/17], P < .01) and Tmax >8 seconds (57.1% [4/7] vs. 15.8% [3/19], P = .05] but not according to Tmax > 4 seconds (27.3% [6/17] vs. 11.1% [1/9], P = .35].

CONCLUSIONS

A target mismatch profile using Tmax > 6 seconds may define tissue at risk in patients with acute symptomatic proximal anterior circulation intracranial stenosis. More studies are needed to confirm our findings.

Variable impact of CSF flow suppression on quantitative 3.0T intracranial vessel wall measurements

BACKGROUND

Flow suppression techniques have been developed for intracranial (IC) vessel wall imaging (VWI) and optimized using simulations; however, simulation results may not translate in vivo.

PURPOSE

To evaluate experimentally how IC vessel wall and lumen measurements change in identical subjects when evaluated using the most commonly available blood and cerebrospinal fluid (CSF) flow suppression modules and VWI sequences.

STUDY TYPE

Prospective.

POPULATION/SUBJECTS

Healthy adults (n = 13; age = 37 ± 15 years) were enrolled.

FIELD STRENGTH/SEQUENCE

A 3.0T 3D T1 /proton density (PD)-weighted turbo-spin-echo (TSE) acquisition with post-readout anti-driven equilibrium module, with and without Delay-Alternating-with-Nutation-for-Tailored-Excitation (DANTE) was applied. DANTE flip angle (8-12°) and TSE refocusing angle (sweep = 40-120° or 50-120°) were varied.

ASSESSMENT

Basilar artery and internal carotid artery (ICA) wall thicknesses, CSF signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and signal ratio (SR) were assessed. Measurements were made by two readers (radiology resident and board-certified neuroradiologist).

STATISTICAL TESTS

A Wilcoxon signed-rank test was applied with corrected two-sided P < 0.05 required for significance (critical P = 0.008, 0.005, and 0.05 for SNR/CNR, SR, and wall thickness, respectively).

RESULTS

A TSE pulse sweep = 40-120° and sweep = 50-120° provided similar (P = 0.55) CSF suppression. Addition of the DANTE preparation reduced CSF SNR from 17.4 to 6.7, thereby providing significant (P < 0.008) improvement in CSF suppression. The DANTE preparation also resulted in a significant (P < 0.008) reduction in vessel wall SNR, but variable vessel wall to CSF CNR improvement (P = 0.87). There was a trend for a difference in blood SNR with vs. without DANTE (P = 0.05). The outer vessel wall diameter and wall thickness values were lower (P < 0.05) with (basilar artery 4.45 mm, 0.81 mm, respectively) vs. without (basilar artery 4.88 mm, 0.97 mm, respectively) DANTE 8°.

DATA CONCLUSION

IC VWI with TSE sweep = 40-120° and with DANTE flip angle = 8° provides the best CSF suppression and CNR of the approaches evaluated. However, improvements are heterogeneous, likely owing to intersubject vessel pulsatility and CSF flow variations, which can lead to variable flow suppression efficacy in these velocity-dependent modules.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;48:1120-1128.