Brinjikji, Waleed

Purpose This study sought to validate whether the signal intensity ratio (SIR) of carotid intraplaque hemorrhage (IPH) was associated with acute ischemic neurologic events. Methods A retrospective review was completed of consecutive patients that underwent neck magnetic resonance angiography using magnetization prepared-rapid gradient echo (MP-RAGE) and T1-CUBE sequences between 2017 and 2020. Patients with magnetic resonance evidence of IPH were included. SIRs were measured by comparing the maximum IPH signal with the mean intramuscular signal from the adjacent sternocleidomastoid. Patients were stratified into ischemic or non-ischemic groups based on the presence of acute ipsilateral ischemic events (stroke, retinal artery occlusion). Logistic regression analysis was performed to determine if increasing IPH SIR was associated with an increased risk of ipsilateral ischemic events. Results Of 85 included patients (85 arteries), 66 were male (77.6%). Mean age was 71.0 (SD ± 11.1). There were 70 arteries with IPH that were ipsilateral to an ischemic event, and 15 that belonged to patients without an ischemic event. No association was found between increasing IPH SIR seen on MP-RAGE (odds ratio (OR): 0.82; 95% confidence interval (CI): 0.58–1.4; P = 0.43) or T1-CUBE sequences (OR: 0.85; 95% CI: 0.53–1.5; P = 0.56). Conclusions There was no association between the SIR of IPH and acute ischemia on either MP-RAGE or T1-CUBE sequences. Further investigation is required prior to widespread acceptance of SIR as a predictive imaging marker of symptomatic carotid plaque.

Background While venous congestion in the peripheral vasculature has been described and accepted, intracranial venous congestion remains poorly understood. The characteristics, pathophysiology, and management of cerebral venous stasis, venous hypertension and venous congestion remain controversial, and a unifying conceptual schema is absent. The cerebral venous and lymphatic systems are part of a complex and dynamic interaction between the intracranial compartments, with interplay between the parenchyma, veins, arteries, cerebrospinal fluid, and recently characterized lymphatic-like systems in the brain. Each component contributes towards intracranial pressure, occupying space within the fixed calvarial volume. This article proposes a framework to consider conditions resulting in brain and neck venous congestion, and seeks to expedite further study of cerebral venous diagnoses, mechanisms, symptomatology, and treatments. Methods A multi-institution retrospective review was performed to identify unique patient cases, complemented with a published case series to assess a spectrum of disease states with components of venous congestion affecting the brain. These diseases were organized according to anatomical location and purported mechanisms. Outcomes of treatments were also analyzed. Illustrative cases were identified in the venous treatment databases of the authors. Conclusion This framework is the first clinically structured description of venous pathologies resulting in intracranial venous and cerebrospinal fluid hypertension. Our proposed system highlights unique clinical symptoms and features critical for appropriate diagnostic work-up and potential treatment. This novel schema allows clinicians effectively to approach cases of intracranial hypertension secondary to venous etiologies, and furthermore provides a framework by which researchers can better understand this developing area of cerebrovascular disease.

Background and Purpose: We performed a systematic review and meta-analysis comparing rates of recanalization, good neurological outcome, and mortality between patients treated with three modern devices used for endovascular treatment of acute ischemic stroke. Materials and Methods: We performed a comprehensive literature search on studies reporting outcomes of endovascular treatment of acute ischemic stroke. We selected studies including≥30 patients treated with either the Trevo stent-retriever, Penumbra aspiration system or the Solitaire stent-retriever. Outcomes studied included mrs≤2, 90-day mortality, symptomatic and intracranial hemorrhage (sICH), recanalization. Outcomes were pooled across studies using a random-effects meta-analysis. Results: 27 articles with 2666 patients were included (1514 Solitaire, 260 Trevo and 892 Penumbra). Rates of good neurological outcome (mRS≤2) were higher in the Solitaire group (54.0%, 95%CI=49.0-58.0%) than the Penumbra group (39.0%, 95%CI=31.0%-47.0%) (P<0.01). There was a trend towards higher rates of good neurological outcome in the Solitaire compared to the Trevo group (P=0.08). Rates of 90-day mortality were significantly lower in the Solitaire group (16.0%, 95%CI=11.0%-22.0%) than in the Penumbra group (27.0%, 95%CI=24.0%-30.0%) (P<0.01) and the Trevo group (23.0%, 95%CI=13.0-33.0)(P=0.01). Recanalization rates were similar between groups at 80.0% (95%CI=75.0%-84.0% for the Solitaire group, 82.0% (95%CI=75.0%-88.0%) for the Penumbra group (P=0.54) and 76.0% (95%CI=68.0-83.0) for the Trevo group (P=0.13 vs Penumbra and P=0.27 vs. Solitaire). Conclusions: Meta-analysis of incidence rates in noncomparative series reporting on over 2500 patients suggests that the Solitaire device maybe associated with superior neurological outcomes and lower rates of 90-day mortality. Comparative studies are needed to confirm these observations.

Introduction: Five randomized trials proving the efficacy and safety of mechanical embolectomy for ischemic stroke patients used differing radiological methods to select patients for treatment. Hypothesis: The percentage of patients evaluated in a non-clinical trial setting that would meet radiological criteria to be included in the five trials will differ substantially. Methods: Retrospective study of consecutive ischemic stroke patients who were considered for endovascular stroke therapy based on confirmed intracranial large vessel occlusion (M1, M2, or carotid terminus) at an academic medical center from April 2010 - November 2014. All patients underwent CT perfusion and CT angiogram. Results: The table shows baseline characteristics of 119 patients. Median age was 69 years (IQR 57-79) and median NIHSS 18 (IQR 14-21). Most patients had ASPECTS score ≥ 6 (n=105, 88.2%). The M1 segment of MCA was the most common vessel occluded (n=81, 68%). All 119 patients (100%) met radiological criteria for MR CLEAN while 105 (88.2%) met criteria for SWIFT-PRIME, 96 (80.7%) for REVASCAT, 80/116 (69.0%) for EXTEND IA, and 74 (62.2%) for ESCAPE. IV TPA was given to 58 patients (48.7%) and acute endovascular stroke therapy attempted in 66 (55.5%). Any intracranial hemorrhage was more common in the patients treated with endovascular therapy than in those who were not (36% vs. 17%, p=0.025). The frequency of symptomatic ICH did not significantly differ between these two groups (6.1% vs 3.8%, p=0.691). Conclusions: The percentage of patients with acute stroke and large vessel occlusion that would qualify for endovascular stroke trials based on radiological criteria varies considerably (62%-100%) in a non-clinical trial cohort from an academic comprehensive stroke center. Additional individual patient characteristics influence treatment decisions in non-clinical trial settings.

Background and Purpose: Ultrasound is the most commonly used imaging modality for assessment of carotid artery stenosis. A number of studies have demonstrated that surface irregularities, heterogeneous echotexture and hypoechoic plaques are risk factors for acute ischemic stroke. We performed a systematic review and meta-analysis of the literature to better define the risk of stroke based off of the sonographic characteristics of carotid plaques. Materials and Methods: We performed a comprehensive literature search evaluating the association of carotid plaque characteristics on ultrasound with ischemic outcomes. We included both case-control and cohort studies examining the relationship between complex plaque and acute ischemic stroke. Complex plaque was defined as plaque that had any of the following characteristics: heterogeneous plaque echogenicity, hypoechoic plaque, plaque neovascularization, plaque surface irregularity, plaque ulceration, and intraplaque motion. Meta-analyses using the random-effects model were performed for complex plaque and each of the individual complex plaque characteristics. Results: A total of 1013 articles were screened and 30 studies with 11528 patients (3054 symptomatic and 8474 asymptomatic) were included. The odds ratios for the association between complex plaque and ischemic symptoms was 5.18 (95%CI=4.63-5.79). Heterogeneous echotexture (OR=11.72, 95%CI=9.82-13.98), intraplaque motion (OR=1.57, 95%CI=1.02-2.41), plaque echolucency (OR=3.23, 95%CI=2.72-3.84), plaque neovascularity (OR=5.66, 95%CI=3.15-10.16) and plaque ulceration (OR=2.65, 95%CI=1.89-3.73) were all associated with ischemic symptoms. Surface irregularity without frank ulceration was not associated with ischemic symptoms (OR=1.35, 95%CI=0.98-1.86). Conclusions: Complex plaque, heterogeneous plaque echogenicity, hypoechoic plaque, plaque neovascularization, plaque ulceration and intraplaque motion are associated with ischemic symptoms. Assessment of carotid plaque on ultrasound provides stroke risk information beyond measurement of luminal stenosis.

Background and Purpose: The Hydrocoil Endovascular aneurysm occlusion and Packing Study (HELPS) was a randomized controlled trial comparing Hydrocoil to bare platinum coils . We performed a subgroup analysis of angiographic and clinical outcomes of medium sized aneurysms in the HELPS trial. Methods: We selected all patients with medium sized aneurysms (5mm-9.9mm) in the HELPS trial. The following outcomes were compared between the HydroCoil and control groups: 1) any recurrence, 2) major recurrence, 3) retreatment and 4) good neurological outcome defined as mRS≤2. Outcomes of recently ruptured and non-recently ruptured aneurysms were compared separately. Comparisons between groups were performed using Fisher’s exact test. A multivariate logistic regression analysis adjusting for aneurysm neck size, shape, use of adjunctive device and rupture status was performed. Results: A total of 288 patients with medium sized aneurysms were randomized (144 in each group). At 15-18 months post-treatment, major recurrence rate was significantly lower in the HydroCoil group than the control group (18.6% versus 30.8%, P=0.03, respectively). For recently ruptured aneurysm patients, major recurrence rate was significantly lower for HydroCoil than controls (20.3% versus 47.5%, P=0.003), while rates were similar between coil types for unruptured aneurysms (16.7% versus 14.8%, P=0.80). On multivariate analysis for patients with recently ruptured aneurysms, HydroCoil was associated with lower odds of any recurrence as compared to bare platinum (OR=0.37, 95%CI=0.18-0.76, P=0.006) and major recurrence (OR=0.27, 95%CI=0.12-0.58, P=0.0007). There was a trend towards lower retreatment rates in the recently ruptured group treated with HydroCoil (OR=0.00, 95%CI=0.00-2.01, P=0.12). Conclusion: For recently ruptured, medium sized aneurysms, as compared to bare platinum coils HydroCoils were associated with lower rates of major recurrence that were both statistically significant and clinically relevant. These findings suggest that HydroCoils should be the preferred treatment for this subset of patients.

Background and Purpose- It is important to know the costs for hospitalization for endovascular embolectomy patients so that comparisons can be made to payments to hospitals. Methods- Using the National Inpatient Sample, we evaluated the costs for hospitalization for patients treated with endovascular embolectomy in the United States from 2006-2008. The primary endpoint examined in this study was total hospital costs, and these were correlated with clinical outcome. Hospitalization costs were then compared with Medicare payments for their respective outcomes. MS-DRG 24 was the diagnostic related group code (DRG) for mechanical embolectomy with good outcome and MS-DRG 23 was the DRG code for mechanical embolectomy with major complications. Medicare payments were available at http://www.cms.hhs.gov . Results- A total of 3864 patients received endovascular embolectomy. 1649 patients were <65 years old and 2205 patients were ≥65 years old. Median hospital costs in 2008 dollars were $36,999 (IQR $26,662-$56,405) for patients with good outcome, $50,628 (IQR $33,135-$76,063) for patients with severe disability, and $35,109 (IQR $25,053-$62,621) for patients with mortality. Reimbursement in the year 2008 for DRG 24 (good outcome) was $22075 and reimbursement for DRG 23 (major complications) was $26639. Conclusions- Our study of the NIS shows that hospitalization costs in the United States for ischemic stroke patients treated with endovascular embolectomy are rather high, probably due to the serious nature of their illness. Medicare payments have not been adequate in reimbursing these hospitalizations. Further work is needed to ensure the future reconciliation of costs with payments.

Background and aim The use of endoluminal flow diversion in bifurcation aneurysms has been questioned due to the potential for complications and lower occlusion rates. In this study we assessed outcomes of endovascular treatment of intracranial sidewall and bifurcation aneurysms with flow diverters Methods In July 2020, a literature search for all studies utilizing endoluminal flow diverter treatment for sidewall or bifurcation aneurysms was performed. Data were collected from studies that met our inclusion/exclusion criteria by two independent reviewers and confirmed by a third reviewer. Using random-effects meta-analysis the target outcomes including overall complications (hematoma, ischemic events, minor ischemic stroke, aneurysm rupture, side vessel occlusion, stenosis, thrombosis, transient ischemic stroke, and other complications), perioperative complications, and follow-up (long-term) aneurysm occlusion were intestigated. Results Overall, we included 35 studies with 1084 patients with 1208 aneurysms. Of these aneurysms, 654 (54.14%) and 554 (45.86%) were classified as sidewall and bifurcation aneurysm, respectively, based on aneurysm location. Sidewall aneurysms had a similar total complication rate (R) of 27.12% (95% CI, 16.56%–41.09%), compared with bifurcation aneurysms (R, 20.40%, 95% CI, 13.24%–30.08%) (p = 0.3527). Follow-up angiographic outcome showed comparable complete occlusion rates for sidewall aneurysms (R 69.49%; 95%CI, 62.41%–75.75%) and bifurcation aneurysms (R 73.99%; 95% CI, 65.05%–81.31%; p = 0.4328). Conclusions This meta-analysis of sidewall and bifurcation aneurysms treated with endoluminal flow diverters demonstrated no significant differences in complications or occlusion rates. These data provide new information that can be used as a benchmark for comparison with emerging devices for the treatment of bifurcation aneurysms.

Introduction: Von Willebrand factor (VWF) is a key component of acute ischemic stroke (AIS) thrombi. The aim of our prospective study was to investigate the immunohistochemical expression of VWF in clots and to evaluate whether VWF is associated with certain subtypes of AIS. Methods: VWF immunostaining was performed on 79 thrombi collected as part of the multi-center Stroke Thromboembolism Registry of Imaging and Pathology (STRIP) registry. The cases were classified according to TOAST criteria. The VWF expression was quantified using Orbit Image Analysis (www.Orbit.bio) machine learning software. IBM SPSS statistics 25 was used to assess the relationship between the VWF levels and different etiology subtypes. Results: A cardioembolic stroke was defined in 39 cases (49.4%) whereas an atherosclerotic origin was identified in 13 patients (16.5%). Other causes accounted for 12 cases (15.1%). Unknown etiology was reported in 15 cases (19%). The mean VWF content in the clots was 12.8%. According to the Mann-Whitney U-test, the level of VWF was significantly higher in the cases with unknown etiology compared to cardioembolic origin (p=0.044). We found also that patients with unknown etiology of stroke had higher VWF expression as compared to the other two subtypes, although this difference was not statistically significant. Conclusions: Among the patients with ischemic stroke included in this study, the VWF expression was significantly increased in those with unknown etiology compared to the group with cardioembolic stroke. Our finding provides new insights into clot composition in cryptogenic stroke and may influence the treatment and secondary prevention in these cases.