Predictors for Cerebral Edema in Acute Ischemic Stroke Treated With Intravenous Thrombolysis

Evaluating the interaction between hemorrhagic transformation and cerebral edema on functional outcome after ischemic stroke

BACKGROUND

Hemorrhagic transformation (HT) and cerebral edema (CED) are both major complications following ischemic stroke, but few studies have evaluated their overlap. We evaluated the frequency and predictors of CED/HT overlap and whether their co-occurrence impacts functional outcome more than each in isolation.

METHODS

892 stroke patients enrolled in a prospective study had follow-up CT imaging evaluated for HT and CED; the latter was quantified using the ratio of hemispheric CSF volumes (with hemispheric CSF ratio < 0.90 used as the CED threshold). The interaction between HT and CED on functional outcome (using modified Rankin Scale at 3 months) was compared to that for each condition separately.

RESULTS

Among the 275 (31%) who developed HT, 233 (85%) manifested hemispheric CSF ratio < 0.9 (CED/HT), with this overlap group representing half of the 475 with measurable CED. Higher baseline NIHSS scores and larger infarct volumes were observed in the CED/HT group compared with those with CED or HT alone. Functional outcome was worse in those with CED/HT [median mRS 3 (IQR 2-5)] than those with CED [median 2 (IQR 1-4)] or HT alone [median 1 (IQR 0-2), p < 0.0001]. Overlap of CED/HT independently predicted worse outcome [OR 1.89 (95% CI: 1.12-3.18), p = 0.02] while HT did not; however, CED/HT was no longer associated with worse outcome after adjusting for severity of CED [adjusted OR 0.35 (95% CI: 0.23, 0.51) per 0.21 lower hemispheric CSF ratio, p < 0.001].

CONCLUSIONS

Most stroke patients with HT also have measurable CED. The co-occurrence of CED and HT occurs in larger and more severe strokes and is associated with worse functional outcome, although this is driven by greater severity of stroke-related edema in those with HT.

A dynamic nomogram for predict individual risk of malignant brain edema after endovascular thrombectomy in acute ischemic stroke

The aim of this study was to develop a dynamic nomogram combining clinical and imaging data to predict malignant brain edema (MBE) after endovascular thrombectomy (EVT) in patients with large vessel occlusion stroke (LVOS). We analyzed the data of LVOS patients receiving EVT at our center from October 2018 to February 2023, and divided a 7:3 ratio into the training cohort and internal validation cohort, and we also prospectively collected patients from another stroke center for external validation. MBE was defined as a midline shift or pineal gland shift > 5 mm, as determined by computed tomography (CT) scans obtained within 7 days after EVT. A nomogram was constructed using logistic regression analysis, and its receiver operating characteristic curve (ROC) and calibration were assessed in three cohorts. A total of 432 patients were enrolled in this study, with 247 in the training cohort, 100 in the internal validation cohort, and 85 in the external validation cohort. MBE occurred in 24% (59) in the training cohort, 16% (16) in the internal validation cohort and 14% (12) in the external validation cohort. After adjusting for various confounding factors, we constructed a nomogram including the clot burden score (CBS), baseline neutrophil count, core infarct volume on CTP before EVT, collateral index, and the number of retrieval attempts. The AUCs of the training cohorts were 0.891 (95% CI 0.840-0.942), the Hosmer-Lemeshow test showed good calibration of the nomogram (P = 0.879). And our nomogram performed well in both internal and external validation data. Our nomogram demonstrates promising potential in identifying patients at elevated risk of MBE following EVT for LVOS.

Automatic segmentation of hemispheric CSF on MRI using deep learning: Quantifying cerebral edema following large hemispheric infarction

Background and objective

Cerebral edema (CED) is a serious complication of acute ischemic stroke (AIS), especially in patients with large hemispheric infarction (LHI). Herein, a deep learning-based approach is implemented to extract CSF from T2-Weighted Imaging (T2WI) and evaluate the relationship between quantified cerebrospinal fluid and outcomes.

Methods

Patients with acute LHI who underwent magnetic resonance imaging (MRI) were included. We used a deep learning algorithm to segment the CSF from T2WI. The hemispheric CSF ratio was calculated to evaluate its relationship with the degree of brain edema and prognosis in patients with LHI.

Results

For the 93 included patients, the left and right cerebrospinal fluid regions were automatically extracted with a mean Dice similarity coefficient of 0.830. Receiver operating characteristic analysis indicated that hemispheric CSF ratio was an accurate marker for qualitative severe cerebral edema (area under receiver-operating-characteristic curve 0.867 [95% CI, 0.781-0.929]). Multivariate logistic regression analysis of functional prognosis showed that previous stroke (OR = 5.229, 95% CI 1.013-26.984), ASPECT≤6 (OR = 13.208, 95% CI 1.136-153.540) and low hemispheric CSF ratio (OR = 0.966, 95% CI 0.937-0.997) were significantly associated with higher chances for unfavorable functional outcome in patients with LHI.

Conclusions

Automated assessment of CSF volume provides an objective biomarker of cerebral edema that can be leveraged to quantify the degree of cerebral edema and confirm its predictive effect on outcomes after LHI.

Effect of short- versus long-term serum glucose levels on early ischemic water homeostasis and functional outcome in patients with large vessel occlusion stroke

BACKGROUND AND PURPOSE

In ischemic stroke, the impact of short- versus long-term blood glucose level (BGL) on early lesion pathophysiology and functional outcome has not been assessed. The purpose of this study was to directly compare the effect of long-term blood glucose (glycated hemoglobin [HbA1c]) versus serum BGL on early edema formation and functional outcome.

METHODS

Anterior circulation ischemic stroke patients who underwent mechanical thrombectomy after multimodal computed tomography (CT) on admission were analyzed. Endpoints were early ischemic cerebral edema, measured by quantitative net water uptake (NWU) on initial CT and functional independence at Day 90.

RESULTS

A total of 345 patients were included. Patients with functional independence had significantly lower baseline NWU (3.1% vs. 8.3%; p < 0.001) and lower BGL (113 vs. 123 mg/dL; p < 0.001) than those without functional independence, while HbA1c levels did not differ significantly (5.7% vs. 5.8%; p = 0.15). A significant association was found for NWU and BGL (ß = 0.02, 95% confidence interval [CI] 0.006-0.03; p = 0.002), but not for HbA1c and NWU (ß = -0.16, 95% CI -0.53-0.21; p = 0.39). Mediation analysis showed that 67% of the effect of BGL on functional outcome was mediated by early edema formation.

CONCLUSION

Aggravated early edema and worse functional outcome was associated with elevated short-term serum BGL, but not with HbA1c levels. Hence, the link between short-term BGL and early edema development might be used as a target for adjuvant therapy in patients with ischemic stroke.

Early venous filling after mechanical thrombectomy in acute ischemic stroke due to large vessel occlusion in anterior circulation

BACKGROUND

The significance of early venous filling (EVF) after mechanical thrombectomy (MT) in acute ischemic stroke (AIS) is not fully understood. In this study, we aimed to investigate the impact of EVF after MT.

METHODS

From January 2019 to May 2022, AIS patients with successful recanalization (modified Thrombolysis in Cerebral Infarction score (mTICI) ≥2b) after MT were retrospectively reviewed. EVF was evaluated on final digital subtraction angiography runs after successful recanalization and was categorized into phase subgroups (arterial phase and capillary phase) and pathway subgroups (cortical veins subgroup and thalamostriate veins subgroup), respectively. The impact of EVF subgroups on functional outcomes after successful recanalization were both investigated.

RESULTS

A total of 349 patients achieving successful recanalization after MT were included, including 45 patients in the EVF group and 304 patients in the non-EVF group. Multivariable logistic regression analysis showed the EVF group had a higher rate of intracranial hemorrhage (ICH; 66.7% vs 22%, adjusted odds ratio (aOR) 6.805, 95% CI 3.389 to 13.662, P<0.001), symptomatic ICH (sICH; 28.9% vs 4.9%, aOR 6.011, 95% CI 2.493 to 14.494, P<0.001) and malignant cerebral edema (MCE; 20% vs 6.9%, aOR 2.682, 95% CI 1.086 to 6.624, P=0.032) than the non-EVF group. Furthermore, the cortical veins subgroup of EVF had a higher rate of mortality than the thalamostriate veins subgroup (37.5% vs 10.3%, P=0.029).

CONCLUSIONS

EVF is independently associated with ICH, sICH and MCE after successful recanalization of MT, but not with favorable outcome and mortality.

Reperfusion by endovascular thrombectomy and early cerebral edema in anterior circulation stroke: Results from the SITS-International Stroke Thrombectomy Registry

BACKGROUND

A large infarct and expanding cerebral edema (CED) due to a middle cerebral artery occlusion confers a 70% mortality unless treated surgically. There is still conflicting evidence whether reperfusion is associated with a lower risk for CED in acute ischemic stroke.

AIM

To investigate the association of reperfusion with development of early CED after stroke thrombectomy.

METHODS

From the SITS-International Stroke Thrombectomy Registry, we selected patients with occlusion of the intracranial internal carotid or middle cerebral artery (M1 or M2). Successful reperfusion was defined as mTICI ⩾ 2b. Primary outcome was moderate or severe CED, defined as focal brain swelling ⩾1/3 of the hemisphere on imaging scans at 24 h. We used regression methods while adjusting for baseline variables. Effect modification by severe early neurological deficits, as indicators of large infarct at baseline and at 24 h, were explored.

RESULTS

In total, 4640 patients, median age 70 years and median National Institutes of Health Stroke Score (NIHSS) 16, were included. Of these, 86% had successful reperfusion. Moderate or severe CED was less frequent among patients who had reperfusion compared to patients without reperfusion: 12.5% versus 29.6%, p < 0.05, crude risk ratio (RR) 0.42 (95% confidence interval (CI): 0.37-0.49), and adjusted RR 0.50 (95% CI: 0.44-0.57). Analysis of effect modification indicated that severe neurological deficits weakened the association between reperfusion and lower risk of CED. The RR reduction was less favorable in patients with severe neurological deficits, defined as NIHSS score 15 or more at baseline and at 24 h, used as an indicator for larger infarction.

CONCLUSION

In patients with large artery anterior circulation occlusion stroke who underwent thrombectomy, successful reperfusion was associated with approximately 50% lower risk for early CED. Severe neurological deficit at baseline seems to be a predictor for moderate or severe CED also in patients with successful reperfusion by thrombectomy.

Epidemiology and Outcomes of Cerebral Edema in Hospitalized Children

BACKGROUND

Cerebral edema can be a consequence of multiple disease processes. Untreated cerebral edema can be fatal, and even with aggressive management, it can be devastating. The objective of this study was to describe the prevalence, underlying causes, and outcomes of cerebral edema in hospitalized children.

METHODS

A retrospective cross-sectional study using the 2016 Kids' Inpatient Database was performed. Children aged one month to 20 years were included. Sample weighting was employed to produce national estimates. Univariate analyses were used to compare those who died and survived. Multivariable logistic regression was performed to assess the influence of demographic variables and etiologic factors on mortality.

RESULTS

Cerebral edema was documented in 4903 children of 2,210,263 (2.2 of 1000) discharges. Among children with cerebral edema, males were 57%, white children were 47.9%, and adolescents were 48.9%. The three most common etiologies associated with cerebral edema in this cohort were stroke (21.7%), anoxic injury (21.4%), and central nervous system (CNS) malignancy (16%). The overall hospital mortality rate was 29.4%. The adjusted mortality rate was significantly higher when cerebral edema was associated with anoxic injury (84%). The mortality was lower when cerebral edema was associated with CNS malignancy (9.5%) or diabetic ketoacidosis (DKA) (4.3%).

CONCLUSIONS

Cerebral edema is uncommon in hospitalized children but has a high mortality. Stroke and anoxic brain injury are the two most common etiologies for cerebral edema in hospitalized children in the United States. Among all etiologies for cerebral edema in children, anoxic brain injury has the highest mortality, whereas DKA has the lowest mortality.

Dual role of Vascular Endothelial Growth Factor-C (VEGF-C) in post-stroke recovery

Using a mouse model of ischemic stroke, this study characterizes stroke-induced lymphangiogenesis at the cribriform plate (CP). While blocking CP lymphangiogenesis with a VEGFR-3 inhibitor improves stroke outcome, administration of VEGF-C induced larger brain infarcts.

Abstract

Cerebrospinal fluid (CSF), antigens, and antigen-presenting cells drain from the central nervous system (CNS) into lymphatic vessels near the cribriform plate and dural meningeal lymphatics. However, the pathological roles of these lymphatic vessels surrounding the CNS during stroke are not well understood. Using a mouse model of ischemic stroke, transient middle cerebral artery occlusion (tMCAO), we show that stroke induces lymphangiogenesis near the cribriform plate. Interestingly, lymphangiogenesis is restricted to lymphatic vessels at the cribriform plate and downstream cervical lymph nodes, without affecting the conserved network of lymphatic vessels in the dura. Cribriform plate lymphangiogenesis peaks at day 7 and regresses by day 14 following tMCAO and is regulated by VEGF-C/VEGFR-3. These newly developed lymphangiogenic vessels transport CSF and immune cells to the cervical lymph nodes. Inhibition of VEGF-C/VEGFR-3 signaling using a blocker of VEGFR-3 prevented lymphangiogenesis and led to improved stroke outcomes at earlier time points but had no effects at later time points following stroke. Administration of VEGF-C after tMCAO did not further increase post-stroke lymphangiogenesis, but instead induced larger brain infarcts. The differential roles for VEGFR-3 inhibition and VEGF-C in regulating stroke pathology call into question recent suggestions to use VEGF-C therapeutically for stroke.

Determinants of urinary tract infection in hospitalized patients with acute ischemic stroke

BACKGROUND

Stroke is a major cause of morbidity and mortality worldwide. Urinary tract infection (UTI) is a common post-acute ischemic stroke (AIS) complication. We assessed the incidence, determinant factors, infection characteristics, post-stroke complications, and outcomes of hospitalized AIS patients with UTI.

METHODS

This retrospective cohort study included AIS patients admitted within 7 days of stroke onset. The patients were divided into the UTI group and the non-UTI (control) group. Clinical data were collected and compared between the groups.

RESULTS

There were 342 AIS patients (31 with UTIs and 311 controls). The multivariate analysis showed that an initial National Institutes of Health Stroke Scale (NIHSS) score of ≥ 15 (odds ratio [OR] 5.00, 95% confidence interval [CI] 1.33-18.72) and Foley catheter retention (OR 14.10, 95% CI 3.25-61.28) were risk factors for UTI, whereas smoking (OR 0.08, 95% CI 0.01-0.50), an initial systolic blood pressure (SBP) of > 120 mmHg (OR 0.06, 95% CI 0.01-0.31), and statin use (OR 0.02, 95% CI 0.0006-0.42) were protective factors. Twenty cases (64.5%) were community-acquired and 11 cases (35.3%) were hospital-acquired. Ten patients (32.3%) had catheter-associated UTIs. The most common pathogen was Escherichia coli (13 patients, 41.9%). Post-stroke complications were significantly more common in the UTI group, including pneumonia, respiratory failure, sepsis, brain edema, seizure, symptomatic hemorrhagic transformation, congestive heart failure, atrial fibrillation with a rapid ventricular response, acute kidney injury, and hyponatremia. The median length of stay (LOS) in the UTI group was 12 days versus 3 days in the control group (p < 0.001). The median 3-month modified Rankin Scale score was higher (5 in UTI and 2 in control; p < 0.001) and the median 3-month Barthel Index was lower (0 in UTI and 100 in control; p < 0.001) in the UTI group than in the control group.

CONCLUSIONS

The risk factors for post-AIS UTI included severe stroke (NIHSS score ≥ 15) and urethral catheter indwelling. An initial SBP of > 120 mmHg and statin use were protective factors. The UTI group had significantly worse post-stroke complications, a longer LOS, and worse 3-month outcomes. Smoking was protective, which requires further investigation.

A Novel Nomogram for Predicting Malignant Cerebral Edema After Endovascular Thrombectomy in Acute Ischemic Stroke: A Retrospective Cohort Study

BACKGROUND

Malignant cerebral edema (MCE) is a common and feared complication after endovascular thrombectomy (EVT) in acute ischemic stroke (AIS). This study aimed to establish a nomogram to predict MCE in anterior circulation large vessel occlusion stroke (LVOS) patients receiving EVT in order to guide the postoperative medical care in the acute phase.

METHODS

In this retrospective cohort study, 381 patients with anterior circulation LVOS receiving EVT were screened from 636 hospitalized patients with LVOS at 2 stroke medical centers. Clinical baseline data and imaging data were collected within 2-5 days of admission to the hospital. The patients were divided into 2 groups based on whether MCE occurred after EVT. Multivariate logistic regression analysis was used to evaluate the independent risk factors for MCE and to establish a nomogram.

RESULTS

Sixty-six patients out of 381 (17.32%) developed MCE. The independent risk factors for MCE included admission National Institutes of Health Stroke Scale (NIHSS) ≥16 (odds ratio [OR] 1.851; 95% CI 1.029-3.329; P = 0.038), ASPECT score (OR 0.621; 95% CI 0.519-0.744; P < 0.001), right hemisphere (OR 1.636; 95% CI 0.941-2.843; P = 0.079), collateral circulation (OR 0.155; 95% CI 0.074-0.324; P < 0.001), recanalization (OR 0.223; 95% CI 0.109-0.457; P < 0.001), hematocrit (OR, 0.937; 95% CI: 0.892-0.985; P =0.010), and glucose (OR 1.118; 95% CI 1.023-1.223; P = 0.036), which were adopted as parameters of the nomogram. The receiver operating characteristic curve analysis showed that the area under the curve of the nomogram in predicting MCE was 0.901(95% CI 0.848-0.940; P < 0.001). The Hosmer-Lemeshow test results were not significant (P = 0.685), demonstrating a good calibration of the nomogram.

CONCLUSIONS

The novel nomogram composed of admission NIHSS, ASPECT scores, right hemisphere, collateral circulation, recanalization, hematocrit, and serum glucose provide a potential predictor for MCE in patients with AIS after EVT.

Daidzein Ameliorates Cerebral Ischemic-reperfusion Induced Neuroinflammation in Wistar Rats via Inhibiting NF-κB Signaling Pathway

Background

Cerebral ischemia is a condition of acute brain damage due to the depletion of oxygenated blood supply to cerebral tissues. Daidzein is an isoflavonoid predominantly present in soya, Pueraria species, and red cloves. Traditional Chinese medicine utilizes daidzein to alleviate diseases such as inflammation, hyperglycemia, gastric diseases, allergies and aches. The neuroprotective effect of daidzein on cerebral ischemic conditions and its mechanism of action was not yet elucidated.

Materials and Methods

24 healthy male adult Wistar rats were grouped into four and the control rats were sham-operated, cerebral ischemic-reperfusion induced rats subjected to middle cerebral artery occlusion (MCAO). Low- and high-dose daidzein rats were treated with 25 and 50 mg/kg daidzein respectively for 7 consecutive days before the induction of cerebral ischemic reperfusion. On completion of treatment, the rats were assessed for neurological deficit scoring and then euthanized for further analysis. The percentage of brain water content and cerebral infarct was evaluated. The ability of daidzein on preventing oxidative stress-induced damage was assessed by quantifying lipid peroxidation and antioxidant levels. The neuroprotective Daidzein was evaluated by measuring the acetylcholinesterase activity and brain ATP levels. The anti-inflammatory role of Daidzein was measured by quantifying the nitric oxide (NO) and inflammatory cytokines. Further, the anti-ischemic role of Daidzein was confirmed by estimating nuclear factor-kappa B (NF-κB) p65 and Caspase 3 levels.

Results

Daidzein treatment significantly prevented brain edema and cerebral infarction and neurological deficit in cerebral I/R injured rats. It also scavenged the free radicals and prevented the decline in antioxidant levels of ischemic rats. Daidzein decreased the acetylcholinesterase activity, NO, and inflammatory and significantly increased the brain ATP levels signifying its neuroprotective role in ischemic-induced rats. The reduction in the levels of NF-κB p65 and Caspase 3 confirms daidzein prevents neuroinflammation and neuronal apoptosis in ischemic rats.

Conclusion

Overall our analysis confirms daidzein is a potent neuroprotective drug which can effectively inhibit postischemic complications.

The Yin and Yang Effect of the Apelinergic System in Oxidative Stress

Apelin is an endogenous ligand for the G protein-coupled receptor APJ and has multiple biological activities in human tissues and organs, including the heart, blood vessels, adipose tissue, central nervous system, lungs, kidneys, and liver. This article reviews the crucial role of apelin in regulating oxidative stress-related processes by promoting prooxidant or antioxidant mechanisms. Following the binding of APJ to different active apelin isoforms and the interaction with several G proteins according to cell types, the apelin/APJ system is able to modulate different intracellular signaling pathways and biological functions, such as vascular tone, platelet aggregation and leukocytes adhesion, myocardial activity, ischemia/reperfusion injury, insulin resistance, inflammation, and cell proliferation and invasion. As a consequence of these multifaceted properties, the role of the apelinergic axis in the pathogenesis of degenerative and proliferative conditions (e.g., Alzheimer's and Parkinson's diseases, osteoporosis, and cancer) is currently investigated. In this view, the dual effect of the apelin/APJ system in the regulation of oxidative stress needs to be more extensively clarified, in order to identify new potential strategies and tools able to selectively modulate this axis according to the tissue-specific profile.

Neutrophil β1 adrenoceptor blockade blunts stroke-associated neuroinflammation

BACKGROUND AND PURPOSE

Reperfusion therapy is the standard of care for ischaemic stroke; however, there is a need to identify new therapeutic targets able to ameliorate cerebral damage. Neutrophil β₁ adrenoceptors (β1AR) have been linked to neutrophil migration during exacerbated inflammation. Given the central role of neutrophils in cerebral damage during stroke, we hypothesize that β1AR blockade will improve stroke outcomes.

EXPERIMENTAL APPROACH

Rats were subjected to middle cerebral artery occlusion-reperfusion to evaluate the effect on stroke of the selective β1AR blocker metoprolol (12.5 mg·kg^-1 ) when injected i.v. 10 min before reperfusion.

KEY RESULTS

Magnetic resonance imaging and histopathology analysis showed that pre-reperfusion i.v. metoprolol reduced infarct size. This effect was accompanied by reduced cytotoxic oedema at 24 h and vasogenic oedema at 7 days. Metoprolol-treated rats showed reduced brain neutrophil infiltration and those which infiltrated displayed a high proportion of anti-inflammatory phenotype (N2, YM1⁺ ). Additional inflammatory models demonstrated that metoprolol specifically blocked neutrophil migration via β1AR and excluded a significant effect on the glia compartment. Consistently, metoprolol did not protect the brain in neutrophil-depleted rats upon stroke. In patients suffering an ischaemic stroke, β1AR blockade by metoprolol reduced circulating neutrophil-platelet co-aggregates.

CONCLUSIONS AND IMPLICATIONS

Our findings describe that β1AR blockade ameliorates cerebral damage by targeting neutrophils, identifying a novel therapeutic target to improve outcomes in patients with stroke. This therapeutic strategy is in the earliest stages of the translational pathway and should be further explored.

Cerebral Edema in Patients with severe Hemispheric Syndrome: Incidence, Risk Factors, and Outcomes-Data from SITS-ISTR

BACKGROUND AND PURPOSE

Cerebral edema (CED) in ischemic stroke can worsen prognosis and about 70% of patients who develop severe CED die if treated conservatively. We aimed to describe incidence, risk factors and outcomes of CED in patients with extensive ischemia.

METHODS

Oservational study based on Safe Implementation of Treatments in Stroke-International Stroke Treatment Registry (2003-2019). Severe hemispheric syndrome (SHS) at baseline and persistent SHS (pSHS) at 24 hours were defined as National Institutes of Health Stroke Score (NIHSS) >15. Outcomes were moderate/severe CED detected by neuroimaging, functional independence (modified Rankin Scale 0-2) and death at 90 days.

RESULTS

Patients (n=8,560) presented with SHS and developed pSHS at 24 hours; 82.2% received intravenous thrombolysis (IVT), 10.5% IVT+thrombectomy, and 7.3% thrombectomy alone. Median age was 77 and NIHSS 21. Of 7,949 patients with CED data, 3,780 (47.6%) had any CED and 2,297 (28.9%) moderate/severe CED. In the multivariable analysis, age <50 years (relative risk [RR], 1.56), signs of acute infarct (RR, 1.29), hyperdense artery sign (RR, 1.39), blood glucose >128.5 mg/dL (RR, 1.21), and decreased level of consciousness (RR, 1.14) were associated with moderate/severe CED (for all P<0.05). Patients with moderate/severe CED had lower odds to achieve functional Independence (adjusted odds ratio [aOR], 0.35; 95% confidence interval [CI], 0.23 to 0.55) and higher odds of death at 90 days (aOR, 2.54; 95% CI, 2.14 to 3.02).

CONCLUSIONS

In patients with extensive ischemia, the most important predictors for moderate/ severe CED were age <50, high blood glucose, signs of acute infarct, hyperdense artery on baseline scans, and decreased level of consciousness. CED was associated with worse functional outcome and a higher risk of death at 3 months.

Association of cholesterol levels with hemorrhagic transformation and cerebral edema after reperfusion therapies

Background:

The association between cholesterol levels and cerebral edema (CED) or hemorrhagic transformation (HT) as an expressions of blood-brain barrier (BBB) dysfunction after ischemic stroke is not well established. The aim of this study is to determine the association of total cholesterol (TC) levels with the incidence of HT and CED after reperfusion therapies.

Methods:

We analyzed SITS Thrombolysis and Thrombectomy Registry data from January 2011 to December 2017. We identified patients with data on TC levels at baseline. TC values were categorized in three groups (reference group ⩾200 mg/dl). The two primary outcomes were any parenchymal hemorrhage (PH) and moderate to severe CED on follow up imaging. Secondary outcomes included death and functional independence (mRS 0–2) at 3 months. Multivariable logistic regression analysis adjusted for baseline factors including statin pretreatment was used to assess the association between TC levels and outcomes.

Results:

Of 35,314 patients with available information on TC levels at baseline, 3372 (9.5%) presented with TC levels ⩽130 mg/dl, 8203 (23.2%) with TC 130–200 mg/dl and 23,739 (67.3%) with TC ⩾ 200 mg/dl. In the adjusted analyses, TC level as continuous variable was inversely associated with moderate to severe CED (OR 0.99, 95% CI 0.99–1.00, p = 0.025) and as categorical variable lower TC levels were associated with a higher risk of moderate to severe CED (aOR 1.24, 95% CI 1.10–1.40, p = 0.003). TC levels were not associated with any PH, functional independence, and mortality at 3 months.

Conclusions:

Our findings indicate an independent association between low levels of TC and higher odds of moderate/severe CED. Further studies are needed to confirm these findings.

A clinical application study of a stent placement assessment

BACKGROUND

Atherosclerotic acute carotid occlusion is a specific type of stroke, and controversy exists regarding the surgical strategy, that is, whether an internal carotid artery stent should be placed immediately after opening the occluded vessel. There is no objective evaluation system for this procedure. In a previous study, we summarized an evaluation decision system Emergent Carotid Artery Stent placement decision Evaluation System (ECASES) for emergency stent placement.

STUDY DESIGN

This is a prospective, single-center, randomized controlled trial. Patients with acute ischemic stroke caused by atherosclerotic carotid artery occlusion confirmed by imaging (computed tomography/magnetic resonance angiography/digital subtraction angiography) will be randomly divided into the study and control groups, with 101 patients in each group. The study group will undergo surgery according to the ECASES system and the control group will undergo surgery according to the operator's experience. The postoperative outcomes of the 2 groups will be compared.

STUDY OUTCOMES

Primary outcome: Neurological functional status (modified Rankin Scale and National Institutes of Health Stroke Scale scores) of patients 90 days postoperatively. Secondary outcomes: neurological function changes, hemorrhage events, cerebral edema, postoperative modified treatment in cerebral infarction grade, new cerebral infarction, and reocclusion of responsible vessels.

DISCUSSION

Currently, no prospective controlled data exist regarding the efficacy and safety of carotid stenting in the acute phase. Previously, we had developed an ECASES stent placement system for acute carotid artery occlusion. The present study will evaluate the efficacy and safety of ECASES in a randomized, double-blind prospective study and clarify its guiding significance in acute atherosclerotic carotid artery occlusion surgery.

Association Between Post-procedure Cerebral Blood Flow Velocity and Severity of Brain Edema in Acute Ischemic Stroke With Early Endovascular Therapy

Objectives

We aimed to investigate the association between post-procedure cerebral blood flow velocity (CBFV) and severity of brain edema in patients with acute ischemic stroke (AIS) who received early endovascular therapy (EVT).

Methods

We retrospectively included patients with AIS who received EVT within 24 h of onset between February 2016 and November 2021. Post-procedure CBFV of the middle cerebral artery was measured in the affected and the contralateral hemispheres using transcranial Doppler ultrasound. The severity of brain edema was measured using the three-level cerebral edema grading from the Safe Implementation of Thrombolysis in Stroke-Monitoring Study, with grades 2–3 indicating severe brain edema. The Association between CBFV parameters and severity of brain edema was analyzed.

Results

A total of 101 patients (mean age 64.2 years, 65.3% male) were included, of whom 56.3% (57/101) suffered brain edema [grade 1, 23 (22.8%); grade 2, 10 (9.9%); and grade 3, 24 (23.8%)]. Compared to patients with non-severe brain edema, patients with severe brain edema had lower affected/contralateral ratios of systolic CBFV (median 1 vs. 1.2, P = 0.020) and mean CBFV (median 0.9 vs. 1.3, P = 0.029). Multivariate logistic regression showed that severe brain edema was independently associated with affected/contralateral ratios of systolic CBFV [odds ratio (OR) = 0.289, 95% confidence interval (CI): 0.069–0.861, P = 0.028] and mean CBFV (OR = 0.278, 95% CI: 0.084–0.914, P = 0.035) after adjusting for potential confounders.

Conclusion

Post-procedure affected/contralateral ratio of CBFV may be a promising predictor of brain edema severity in patients with AIS who received early EVT.

Brain Targeting, Antioxidant Polymeric Nanoparticles for Stroke Drug Delivery and Therapy

Ischemic stroke is a leading cause of death and disability and remains without effective treatment options. Improved treatment of stroke requires efficient delivery of multimodal therapy to ischemic brain tissue with high specificity. Here, this article reports the development of multifunctional polymeric nanoparticles (NPs) for both stroke treatment and drug delivery. The NPs are synthesized using an reactive oxygen species (ROS)-reactive poly (2,2'-thiodiethylene 3,3'-thiodipropionate) (PTT) polymer and engineered for brain penetration through both thrombin-triggered shrinkability and AMD3100-mediated targeted delivery. It is found that the resulting AMD3100-conjugated, shrinkable PTT NPs, or ASPTT NPs, efficiently accumulate in the ischemic brain tissue after intravenous administration and function as antioxidant agents for effective stroke treatment. This work shows ASPTT NPs are capable of efficient encapsulation and delivery of glyburide to achieve anti-edema and antioxidant combination therapy, resulting in therapeutic benefits significantly greater than those by either the NPs or glyburide alone. Due to their high efficiency in brain penetration and excellent antioxidant bioactivity, ASPTT NPs have the potential to be utilized to deliver various therapeutic agents to the brain for effective stroke treatment.

A Dynamic Nomogram to Predict the 3-Month Unfavorable Outcome of Patients with Acute Ischemic Stroke

Purpose

Despite receiving standard-of-care treatments, a significant proportion of patients with acute ischemic stroke (AIS) are left with long-term functional impairment. Therefore, an easy-to-use tool for predicting of unfavorable outcome following AIS plays an important role in clinical practice. This study was aimed to develop a dynamic nomogram to predict the 3-month unfavorable outcome for AIS patients.

Methods

This was a prospective observational study conducted in consecutive patients with AIS admitted to our stroke center between September 2019 and June 2020. Baseline demographic, clinical, and laboratory information were obtained. The primary outcome was evaluated with modified Rankin Scale (mRS) scores at 3 months. Least absolute shrinkage and selection operator regression was used to select the optimal predictive factors. Multiple logistics regression was performed to establish the nomogram. Decision curve analysis (DCA) was applied to assess the clinical utility of the nomogram. The calibration and discrimination property of the nomogram was validated by calibration plots and concordance index.

Results

A total of 93 eligible patients were enrolled: 28 (30.1%) patients had unfavorable outcome (mRS >2). Glycosylated hemoglobin (OR, 1.541; 95% CI, 1.051–2.261), the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (OR, 0.635; 95% CI, 0.463–0.871), and National Institute of Health Stroke Scale (NIHSS) (OR 1.484; 95% CI, 1.155–1.907) were significant predictors of the poor outcome of patients with AIS and included into the nomogram model. The nomogram showed good calibration and discrimination. C-index was 0.891 (95% CI, 0.854–0.928). DCA confirmed the clinical usefulness of the model. The dynamic nomogram can be obtained at the website: https://odywong.shinyapps.io/DBT_21/.

Conclusion

The dynamic nomogram, comprised of glycosylated hemoglobin, ASPECTS, and NIHSS score at day 14, may be able to predict the 3-month unfavorable outcome for AIS patients.

D* from diffusion MRI reveals a correspondence between ventricular cerebrospinal fluid volume and flow in the ischemic rodent model

Quantitative measurement of cerebrospinal fluid (CSF) flow and volume and longitudinal monitoring of CSF dynamics provide insights into the compensatory characteristics of post-stroke CSF. In this study, we compared the MRI pseudo-diffusion index (D*) of live and sacrificed rat brains to confirm the effect of ventricular CSF flow on diffusion signals. We observed the relationship between the CSF peak velocities and D* through Monte Carlo (MC) simulations to further understand the source of D* contrast. We also determined the dominant CSF flow using D* in three directions. Finally, we investigated the dynamic evolutions of ventricular CSF flow and volume in a stroke rat model (n = 8) from preoperative to up to 45 days after surgery and determined the correlation between ventricular CSF volume and flow. MC simulations showed a strong positive correlation between the CSF peak velocity and D* (r = 0.99). The dominant CSF flow variations in the 3D ventricle could be measured using the maximum D* map. A longitudinal positive correlation between ventricular CSF volume and D* was observed in the lateral (r = 0.74) and ventral-third (r = 0.81) ventricles, respectively. The directional D* measurements provide quantitative CSF volume and flow information, which would provide useful insights into ischemic stroke with diffusion MRI.

Effect of Intravenous Alteplase on Functional Outcome and Secondary Injury Volumes in Stroke Patients with Complete Endovascular Recanalization

Intravenous thrombolytic therapy with alteplase (IVT) is a standard of care in ischemic stroke, while recent trials investigating direct endovascular thrombectomy (EVT) approaches showed conflicting results. Yet, the effect of IVT on secondary injury volumes in patients with complete recanalization has not been analyzed. We hypothesized that IVT is associated with worse functional outcome and aggravated secondary injury volumes when administered to patients who subsequently attained complete reperfusion after EVT. Anterior circulation ischemic stroke patients with complete reperfusion after thrombectomy defined as thrombolysis in cerebral infarctions (TICI) scale 3 after thrombectomy admitted between January 2013–January 2021 were analyzed. Primary endpoints were the proportion of patients with functional independence defined as modified Rankin Scale (mRS) score 0–2 at day 90, and secondary injury volumes: Edema volume in follow-up imaging measured using quantitative net water uptake (NWU), and the rate of symptomatic intracerebral hemorrhage (sICH). A total of 219 patients were included and 128 (58%) patients received bridging IVT before thrombectomy. The proportion of patients with functional independence was 28% for patients with bridging IVT, and 34% for patients with direct thrombectomy (p = 0.35). The rate of sICH was significantly higher after bridging IVT (20% versus 7.7%, p = 0.01). Multivariable logistic and linear regression analysis confirmed the independent association of bridging IVT with sICH (aOR: 2.78, 95% CI: 1.02–7.56, p = 0.046), and edema volume (aOR: 8.70, 95% CI: 2.57–14.85, p = 0.006). Bridging IVT was associated with increased edema volume and risk for sICH as secondary injury volumes. The results of this study encourage direct EVT approaches, particularly in patients with higher likelihood of successful EVT.

Vision and Visuomotor Performance Following Acute Ischemic Stroke

Background

As measurable sensory and motor deficits are key to the diagnosis of stroke, we investigated the value of objective tablet based vision and visuomotor capacity assessment in acute mild-moderate ischemic stroke (AIS) patients.

Methods

Sixty AIS patients (65 ± 14 years, 33 males) without pre-existing visual/neurological disorders and acuity better than 6/12 were tested at their bedside during the first week post-stroke and were compared to 40 controls (64 ± 11 years, 15 males). Visual field sensitivity, quantified as mean deviation (dB) and visual acuity (with and without luminance noise), were tested on MRFn (Melbourne Rapid Field-Neural) iPad application. Visuomotor capacity was assessed with the Lee-Ryan Eye-Hand Coordination (EHC) iPad application using a capacitive stylus for iPad held in the preferred hand.Time to trace 3 shapes and displacement errors (deviations of >3.5 mm from the shape) were recorded. Diagnostic capacity was considered with Receiver Operating Characteristics. Vision test outcomes were correlated with National Institutes of Health Stroke Scale (NIHSS) score at the admission.

Results

Of the 60 AIS patients, 58 grasped the iPad stylus in their preferred right hand even though 31 had left hemisphere lesions. Forty-one patients (68%) with better than 6/12 visual acuity (19 right, 19 left hemisphere and 3 multi-territorial lesions) returned significantly abnormal visual fields. The stroke group took significantly longer (AIS: 93.4 ± 60.1 s; Controls: 33.1 ± 11.5 s, p < 0.01) to complete EHC tracing and made larger displacements (AIS: 16,388 ± 36,367 mm; Controls: 2,620 ± 1,359 mm, p < 0.01) although both control and stroke groups made similar numbers of errors. EHC time was not significantly different between participants with R (n = 26, 84.3 ± 55.3 s) and L (n = 31, 101.3 ± 64.7 s) hemisphere lesions. NIHSS scores and EHC measures showed low correlations (Spearman R: −0.15, L: 0.17). ROC analysis of EHC and vision tests found high diagnostic specificity and sensitivity for a fail at EHC time, or visual field, or Acuity-in-noise (sensivity: 93%, specificity: 83%) that shows little relationship to NIHSS scores.

Conclusions

EHC time and vision test outcomes provide an easy and rapid bedside measure that complements existing clinical assessments in AIS. The low correlation between visual function, NIHSS scores and lesion site offers an expanded clinical view of changes following stroke.

MRI Radiomics Features From Infarction and Cerebrospinal Fluid for Prediction of Cerebral Edema After Acute Ischemic Stroke

Neuroimaging biomarkers that predict the edema after acute stroke may help clinicians provide targeted therapies and minimize the risk of secondary injury. In this study, we applied pretherapy MRI radiomics features from infarction and cerebrospinal fluid (CSF) to predict edema after acute ischemic stroke. MRI data were obtained from a prospective, endovascular thrombectomy (EVT) cohort that included 389 patients with acute stroke from two centers (dataset 1, n = 292; dataset 2, n = 97), respectively. Patients were divided into edema group (brain swelling and midline shift) and non-edema group according to CT within 36 h after therapy. We extracted the imaging features of infarct area on diffusion weighted imaging (DWI) (abbreviated as DWI), CSF on fluid-attenuated inversion recovery (FLAIR) (CSF_FLAIR) and CSF on DWI (CSF_DWI), and selected the optimum features associated with edema for developing models in two forms of feature sets (DWI + CSF_FLAIR and DWI + CSF_DWI) respectively. We developed seven ML models based on dataset 1 and identified the most stable model. External validations (dataset 2) of the developed stable model were performed. Prediction model performance was assessed using the area under the receiver operating characteristic curve (AUC). The Bayes model based on DWI + CSF_FLAIR and the RF model based on DWI + CSF_DWI had the best performances (DWI + CSF_FLAIR: AUC, 0.86; accuracy, 0.85; recall, 0.88; DWI + CSF_DWI: AUC, 0.86; accuracy, 0.84; recall, 0.84) and the most stability (RSD% in DWI + CSF_FLAIR AUC: 0.07, RSD% in DWI + CSF_DWI AUC: 0.09), respectively. External validation showed that the AUC of the Bayes model based on DWI + CSF_FLAIR was 0.84 with accuracy of 0.77 and area under precision-recall curve (auPRC) of 0.75, and the AUC of the RF model based on DWI + CSF_DWI was 0.83 with accuracy of 0.81 and the auPRC of 0.76. The MRI radiomics features from infarction and CSF may offer an effective imaging biomarker for predicting edema.

Evaluation and Prediction of Post-stroke Cerebral Edema Based on Neuroimaging

Cerebral edema is a common complication of acute ischemic stroke that leads to poorer functional outcomes and substantially increases the mortality rate. Given that its negative effects can be reduced by more intensive monitoring and evidence-based interventions, the early identification of patients with a high risk of severe edema is crucial. Neuroimaging is essential for the assessment and prediction of edema. Simple markers, such as midline shift and hypodensity volume on computed tomography, have been used to evaluate edema in clinical trials; however, advanced techniques can be applied to examine the underlying mechanisms. In this study, we aimed to review current imaging tools in the assessment and prediction of cerebral edema to provide guidance for using these methods in clinical practice.

Microvascular Dysfunction in Blood-Brain Barrier Disruption and Hypoperfusion Within the Infarct Posttreatment Are Associated With Cerebral Edema

BACKGROUND AND PURPOSE

Factors contributing to cerebral edema in the post-hyperacute period of ischemic stroke (first 24-72 hours) are poorly understood. Blood-brain barrier (BBB) disruption and postischemic hyperperfusion reflect microvascular dysfunction and are associated with hemorrhagic transformation. We investigated the relationships between BBB integrity, cerebral blood flow, and space-occupying cerebral edema in patients who received acute reperfusion therapy.

METHODS

We performed a pooled analysis of patients treated for anterior circulation large vessel occlusion in the EXTEND-IA TNK and EXTEND-IA TNK part 2 trials who had MRI with dynamic susceptibility contrast-enhanced perfusion-weighted imaging 24 hours after treatment. We investigated the associations between BBB disruption and cerebral blood flow within the infarct with cerebral edema assessed using 2 metrics: first midline shift (MLS) trichotomized as an ordinal scale of negligible (<1 mm), mild (≥1 to <5 mm), or severe (≥5 mm), and second relative hemispheric volume (rHV), defined as the ratio of the 3-dimensional volume of the ischemic hemisphere relative to the contralateral hemisphere.

RESULTS

Of 238 patients analyzed, 133 (55.9%) had negligible, 93 (39.1%) mild, and 12 (5.0%) severe MLS at 24 hours. The associated median rHV was 1.01 (IQR, 1.00-1.028), 1.03 (IQR, 1.01-1.077), and 1.15 (IQR, 1.08-1.22), respectively. MLS and rHV were associated with poor functional outcome at 90 days (P<0.002). Increased BBB permeability was independently associated with more edema after adjusting for age, occlusion location, reperfusion, parenchymal hematoma, and thrombolytic agent used (MLS cOR, 1.12 [95% CI, 1.03-1.20], P=0.005; rHV β, 0.39 [95% CI, 0.24-0.55], P<0.0001), as was reduced cerebral blood flow (MLS cOR, 0.25 [95% CI, 0.10-0.58], P=0.001; rHV β, -2.95 [95% CI, -4.61 to -11.29], P=0.0006). In subgroup analysis of patients with successful reperfusion (extended Treatment in Cerebral Ischemia 2b-3, n=200), reduced cerebral blood flow remained significantly associated with edema (MLS cOR, 0.37 [95% CI, 0.14-0.98], P=0.045; rHV β, -2.59 [95% CI, -4.32 to -0.86], P=0.004).

CONCLUSIONS

BBB disruption and persistent hypoperfusion in the infarct after reperfusion treatment is associated with space-occupying cerebral edema. Further studies evaluating microvascular dysfunction during the post-hyperacute period as biomarkers of poststroke edema and potential therapeutic targets are warranted.

Effect of Tirofiban on new cerebral microbleeds after mechanical thrombectomy in patients with acute ischemic stroke

OBJECTIVE

The aim of this study was to analyze the effect of tirofiban on new cerebral microhemorrhage after mechanical thrombectomy in patients with acute ischemic stroke.

METHODS

In total, 203 patients with acute ischemic stroke treated by mechanical thrombectomy in our department of neurology were enrolled as the research objects. The patients were divided into two groups: the patients who used tirofiban within 24 h after surgery were assigned to the study group (78 subjects), while patients who did not use tirofiban were assigned to the conventional group (125 subjects). Magnetic resonance imaging was used to detect new-onset cerebral microbleeds in patients with stroke after surgery. The National Institute of Health Stroke Scale, modified ranking scale, and activity of daily living scale were used to assess the prognosis of patients, and the general data and the occurrence of adverse effects between two groups were compared to comprehensively evaluate the efficacy and safety of tirofiban.

RESULTS

The proportion of atrial fibrillation in the research group was significantly lower than that in the conventional group. The research group had a much lower rate of new-onset cerebral microbleeds than the conventional group (p<0.001). There was no significant difference in the proportion of adverse reactions between the two groups (p>0.05).

CONCLUSION

The application of tirofiban in mechanical thrombectomy of patients with acute ischemic stroke has high safety, effectively reduces the occurrence of new cerebral microhemorrhage, and provides a guarantee for patient safety.

Hemispheric CSF volume ratio quantifies progression and severity of cerebral edema after acute hemispheric stroke

As swelling occurs, CSF is preferentially displaced from the ischemic hemisphere. The ratio of CSF volume in the stroke-affected hemisphere to that in the contralateral hemisphere may quantify the progression of cerebral edema. We automatically segmented CSF from 1,875 routine CTs performed within 96 hours of stroke onset in 924 participants of a stroke cohort study. In 737 subjects with follow-up imaging beyond 24-hours, edema severity was classified as affecting less than one-third of the hemisphere (CED-1), large hemispheric infarction (LHI, over one-third the hemisphere), without midline shift (CED-2) or with midline shift (CED-3). Malignant edema was LHI resulting in deterioration, requiring osmotic therapy, surgery, or resulting in death. Hemispheric CSF ratio was lower on baseline CT in those with LHI (0.91 vs. 0.97, p < 0.0001) and decreased more rapidly in those with LHI who developed midline shift (0.01 per hour for CED-3 vs. 0.004/hour CED-2). The ratio at 24-hours was lower in those with midline shift (0.41, IQR 0.30-0.57 vs. 0.66, 0.56-0.81 for CED-2). A ratio below 0.50 provided 90% sensitivity, 82% specificity for predicting malignant edema among those with LHI (AUC 0.91, 0.85-0.96). This suggests that the hemispheric CSF ratio may provide an accessible early biomarker of edema severity.

Therapeutic hypothermia augments the restorative effects of PKC-β and Nox2 inhibition on an in vitro model of human blood-brain barrier

To investigate whether therapeutic hypothermia augments the restorative impact of protein kinase C-β (PKC-β) and Nox2 inhibition on an in vitro model of human blood-brain barrier (BBB). Cells cultured in normoglycaemic (5.5 mM) or hyperglycaemic (25 mM, 6 to 120 h) conditions were treated with therapeutic hypothermia (35 °C) in the absence or presence of a PKC-β inhibitor (LY333531, 0.05 μM) or a Nox2 inhibitor (gp91ds-tat, 50 μM). BBB was established by co-culture of human brain microvascular endothelial cells (HBMECs) with astrocytes (HAs) and pericytes. BBB integrity and function were assessed via transendothelial electrical resistance (TEER) and paracellular flux of sodium fluorescein (NaF, 376 Da). Nox activity (lucigenin assay), superoxide anion production (cytochrome-C reduction assay), cellular proliferative capacity (wound scratch assay) and actin cytoskeletal formation (rhodamine-phalloidin staining) were assessed both in HBMECs and HAs using the specific methodologies indicated in brackets. Therapeutic hypothermia augmented the protective effects of PKC-β or Nox2 inhibition on BBB integrity and function in experimental setting of hyperglycaemia, as evidenced by increases in TEER and concomitant decreases in paracellular flux of NaF. The combinatory approaches were more effective in repairing physical damage exerted on HBMEC and HA monolayers by wound scratch and in decreasing Nox activity and superoxide anion production compared to sole treatment regimen with either agent. Similarly, the combinatory approaches were more effective in suppressing actin stress fibre formation and maintaining normal cytoskeletal structure. Therapeutic hypothermia augments the cerebral barrier-restorative capacity of agents specifically targeting PKC-β or Nox2 pathways.

The evaluation of intracranial pressure evaluation by optic nerve sheath diameter measurement on bedside ultrasonography after ischemic stroke

INTRODUCTION

We aimed to predict intracranial pressure(ICP)after cerebral ischemic stroke by measuring diameter of the optic nerve sheath(ONSD)with bedside ultrasonography(US). In order to see the ICP changes,it was planned to record delta ICP changes at the 3rd and 5th day follow-up of the patients METHOTS: Patients aged 18 years or older who were admitted to the emergency department(ED)with stroke symptoms for one year were included.Demographic data,time elapsed since the onset of symptoms,neurogical status assesment scales,ONSD values measured by US in three time periods(the day the patient was admitted to the ED,the 3rd and 5th days of hospitalization),MDCT findings when the patient was admitted,ONSD values in MDCT,whether they received tissue plasminogen activator(tPA)and whether they underwent decompression surgery were recorded.

RESULTS

The average age of the 82 patients was 67.5(range 33-89)years.Forty-two patients(51.2%)were male.On both the right and left sides,ONSD on the 3rd day was larger(>5 mm)than on first day(p < 0.05). ONSD on the 5th day was larger than on the first day(p > 0.05). All ONSD results measured using both US and MDCT showed a positive correlation between the same eye and contralateral eye measurements(p < 0.05).

DISCUSSION

CT is the most critical radiological method for stroke patients.Transport to radyology unit in unstable patients carries risk and is not recommended.Optic nerve US can be used in the early diagnosis of ICP increase and provides early treatment.The ease of use and safety in unstable patients have increased its popularity.

CONCLUSION

We believe that measuring ONSD using US is an appropriate choice on ICP management in stroke patients.

Comparative study on the efficacy and safety of alteplase and urokinase in the treatment of acute cerebral infarction

BACKGROUND

Acute cerebral infarction (ACI) is a common cerebrovascular disease in clinical practice.

OBJECTIVE

The present study aims to investigate the efficacy and safety of alteplase and urokinase in treating ACI.

METHODS

A total of 96 patients with ACI, who were treated with alteplase and urokinase, were selected as the main subjects. Among these patients, 45 patients with ultra-early acute cerebral infarction, who received intravenous thrombolysis with RT-PA (alteplase), were included in the treatment group, while 51 patients with acute cerebral infarction, who were treated with urokinase in the same time period, were included in the control group.

RESULTS

The National Institute of Health Stroke Scale (NIHSS) scores were significantly lower in the treatment group and control group (P< 0.05) at two hours, seven days and 14 days after thrombolysis, when compared to those before thrombolysis. The bleeding rate was significantly lower in the control group, when compared to the treatment group (P< 0.05).

CONCLUSION

The intravenous thrombolysis with urokinase or alteplase in the ultra-early stage of acute cerebral infarction can reduce the neurological injury symptoms and effectively improve the prognosis of patients with stroke. Urokinase is lower in risk of bleeding, but better in safety, when compared to alteplase.

Apelin-13 attenuates injury following ischemic stroke by targeting matrix metalloproteinases (MMP), endothelin- B receptor, occludin/claudin-5 and oxidative stress

Oxidative stress, an adverse consequence of brain ischemia-reperfusion injury (IRI), activates matrix metalloproteinase enzymes which cause to destruction of extracellular matrix and tight junction proteins. Oxidative stress during stroke increases serum endothelin-1 and endothelin B receptor (ETBR) expression. Apelin-13, an endogenous peptide, is expressed in numerous tissues that regulate diverse physiological and pathological processes. This study aimed to investigate the effect of intravenous (IV) injection of apelin-13 on cerebral vasogenic edema due to brain IRI. Animals were divided into sham, ischemia, and treat groups. IRI model was induced by middle cerebral artery occlusion (MCAO) for 60 min followed by 23 h reperfusion. Apelin-13 was injected into the tail vein 5 min before reperfusion. Neurological defects were evaluated with longa test. Brain water content and BBB permeability were assessed according to cerebral dry-wet weight and brain Evans blue extraction. Malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were measured using the colorimetric method. Expression of occludin and claudin-5, matrix metalloproteinase- 2 and 9 (MMP-2 & 9) and, ETBR were evaluated using Western blot. Brain IRI was associated with BBB breakdowns and vasogenic edema. Apelin-13 significantly reduced BBB permeability and vasogenic edema. Apelin-13 significantly attenuated IRI-related oxidative stress. Apelin-13 decreased expression of mmp-2, 9 and ETBR, prevented from decrement of occludin and claudin-5 expersion, which protected BBB integrity and reduced vasogenic edema. In conclusion, our results have suggested that an IV injection of apelin-13 could somehow reduce vasogenic edema via targeting oxidative stress and ETBR expression.

Accelerating Prediction of Malignant Cerebral Edema After Ischemic Stroke with Automated Image Analysis and Explainable Neural Networks

BACKGROUND

Malignant cerebral edema is a devastating complication of stroke, resulting in deterioration and death if hemicraniectomy is not performed prior to herniation. Current approaches for predicting this relatively rare complication often require advanced imaging and still suffer from suboptimal performance. We performed a pilot study to evaluate whether neural networks incorporating data extracted from routine computed tomography (CT) imaging could enhance prediction of edema in a large diverse stroke cohort.

METHODS

An automated imaging pipeline retrospectively extracted volumetric data, including cerebrospinal fluid (CSF) volumes and the hemispheric CSF volume ratio, from baseline and 24 h CT scans performed in participants of an international stroke cohort study. Fully connected and long short-term memory (LSTM) neural networks were trained using serial clinical and imaging data to predict those who would require hemicraniectomy or die with midline shift. The performance of these models was tested, in comparison with regression models and the Enhanced Detection of Edema in Malignant Anterior Circulation Stroke (EDEMA) score, using cross-validation to construct precision-recall curves.

RESULTS

Twenty of 598 patients developed malignant edema (12 required surgery, 8 died). The regression model provided 95% recall but only 32% precision (area under the precision-recall curve [AUPRC] 0.74), similar to the EDEMA score (precision 28%, AUPRC 0.66). The fully connected network did not perform better (precision 33%, AUPRC 0.71), but the LSTM model provided 100% recall and 87% precision (AUPRC 0.97) in the overall cohort and the subgroup with a National Institutes of Health Stroke Scale (NIHSS) score ≥ 8 (p = 0.0001 vs. regression and fully connected models). Features providing the most predictive importance were the hemispheric CSF ratio and NIHSS score measured at 24 h.

CONCLUSIONS

An LSTM neural network incorporating volumetric data extracted from routine CT scans identified all cases of malignant cerebral edema by 24 h after stroke, with significantly fewer false positives than a fully connected neural network, regression model, and the validated EDEMA score. This preliminary work requires prospective validation but provides proof of principle that a deep learning framework could assist in selecting patients for surgery prior to deterioration.

Interaction Effect of Baseline Serum Glucose and Early Ischemic Water Uptake on the Risk of Secondary Hemorrhage After Ischemic Stroke

Background and Purpose: Intracerebral hemorrhage (ICH) after mechanical thrombectomy (MT) for acute ischemic stroke (AIS) remains a major complication and its early prediction is of high relevance. Baseline serum glucose (BGL) is a known predictor of ICH, but its interaction with early ischemic changes remains uncertain. We hypothesized that BGL interacts with the effect of tissue water uptake on the occurrence of ICH. Methods: Three hundred and thirty-six patients with acute ischemic stroke treated with MT were retrospectively analyzed. ICH was diagnosed within 24 h on non-enhanced CT (NECT) and classified according to the Heidelberg Bleeding Classification. Early tissue water homeostasis has been assessed using quantitative lesion net water uptake (NWU) on admission CT. Multivariate logistic regression was used to identify predictors of ICH. Results: One hundred and seven patients fulfilled the inclusion criteria of which 37 (34.6%) were diagnosed with ICH. Patients with ICH had a significant higher BGL on admission (median 177 mg/dl, IQR: 127-221.75, P < 0.001). In patients with low BGL (<120 mg/dl), higher NWU was associated with 1.34-fold increased likelihood of ICH, while higher NWU was associated with a 2.08-fold increased likelihood of ICH in patients with a high BGL (>200 mg/dl). In multivariable logistic regression analysis, BGL (OR: 1.02, 95% CI: 1.00-1.04, P = 0.01) and NWU (OR: 2.32, 95% CI: 1.44-3.73, P < 0.001) were significantly and independently associated with ICH, showing a significant interaction (P = 0.04). Conclusion: A higher degree of early tissue water uptake and high admission BGL were both independent predictors of ICH. Higher BGL was significantly associated with accelerated effects of NWU on the likelihood of ICH. Although a clear causal relationship remains speculative, stricter BGL control and monitoring may be tested to reduce the risk of ICH in patients undergoing thrombectomy.

Transplantation of 3D MSC/HUVEC spheroids with neuroprotective and proangiogenic potentials ameliorates ischemic stroke brain injury

Ischemic stroke, and the consequent brain cell death, is a common cause of death and disability worldwide. Current treatments that primarily aim to relieve symptoms are relatively inefficient in achieving brain tissue regeneration and functional recovery, and thus novel therapeutic options are urgently needed. Although cell-based therapies have shown promise for treating the infarcted brain, a recurring challenge is the inadequate retention and engraftment of transplanted cells at the target tissue, thereby limiting the ultimate therapeutic efficacy. Here, we show that transplantation of preassembled three-dimensional (3D) spheroids of mesenchymal stem cells (MSCs) and vascular endothelial cells (ECs) results in significantly improved cell retention and survival compared with conventional mixed-cell suspensions. The transplanted 3D spheroids exhibit notable neuroprotective, proneurogenic, proangiogenic and anti-scarring potential as evidenced by clear extracellular matrix structure formation and paracrine factor expression and secretion; this ultimately results in increased structural and motor function recovery in the brain of an ischemic stroke mouse model. Therefore, transplantation of MSCs and ECs using the 3D cell spheroid configuration not only reduces cell loss during cell harvesting/administration but also enhances the resultant therapeutic benefit, thus providing important proof-of-concept for future clinical translation.

Net Water Uptake Calculated in Standardized and Blindly Outlined Regions of the Middle Cerebral Artery Territory Predicts the Development of Malignant Edema in Patients With Acute Large Hemispheric Infarction

Background and purpose: Previous studies have demonstrated that Net Water Uptake (NWU) is associated with the development of malignant edema (ME). The current study aimed to investigate whether NWU calculated in standardized and blindly outlined regions of the middle cerebral artery can predict the development of ME. Methods: We retrospectively included 119 patients suffering from large hemispheric infarction within onset of 24 h. The region of the middle cerebral artery territory was blindly outlined in a standard manner to calculate NWU. Patients were divided into two groups according to the occurrence of ME, which is defined as space-occupying infarct requiring decompressive craniotomy or death due to cerebral hernia in 7 days from onset. The clinical characteristics were analyzed, and the receiver operating characteristic curve (ROC curve) was used to assess the predictive ability of NWU and other factors for ME. Results: Multivariable analysis showed that NWU was an independent predictor of ME (OR 1.168, 95% CI 1.041-1.310). According to the ROC curve, NWU≥8.127% identified ME with good predictive power (AUC 0.734, sensitivity 0.656, specificity 0.862). Conclusions: NWU calculated in standardized and blindly outlined regions of the middle cerebral artery territory is also a good predictor for the development of ME in patients with large hemispheric infarction.

Neutrophil-to-Lymphocyte Ratio Predicts Cerebral Edema and Clinical Worsening Early After Reperfusion Therapy in Stroke

BACKGROUND AND PURPOSE

The mechanisms linking systemic inflammation to poor outcome in ischemic stroke are not fully understood. The authors investigated if peripheral inflammation following reperfusion therapy leads to an increase in cerebral edema (CED), thus hindering the clinical recovery.

METHODS

We designed a single-center study conducted at Centro Hospitalar Universitário São João between 2017 and 2019. Inclusion criteria were being adult, having an anterior circulation acute ischemic stroke, and receiving reperfusion therapy. Neutrophil-to-lymphocyte, platelet-to-lymphocyte ratios, and the systemic inflammatory response syndrome criteria were determined. The presence and grade of CED were evaluated on the computed tomography performed 24 hours following event. The clinical outcomes included early neurological deterioration and functional dependence at 90 days. Adjusted odds ratio and 95% CI were obtained by ordinal and logistic regression models. Optimal cutoff values were defined using receiver operating characteristic analysis in the training cohort and validated in an independent data set.

RESULTS

Five hundred fifty-three patients were included. Neutrophil-to-lymphocyte increased with higher degrees of CED at 24 hours (adjusted odds ratio, 1.34 [1.09-1.68], P<0.01) and was associated with early neurological deterioration (adjusted odds ratio, 1.30 [1.04-1.63], P<0.05) and poor functional status at 90 days (adjusted odds ratio, 1.79 [1.28-2.48], P<0.01). Platelet-to-lymphocyte was not associated with the outcomes. Systemic inflammatory response syndrome was related to CED due to altered white blood cell counts. Neutrophil-to-lymphocyte was the best predictor with an area under the curve around 0.7. Neutrophil-to-lymphocyte ≥7 had and accuracy, sensitivity, and specificity around 60%.

CONCLUSIONS

Increased systemic inflammation is linked to the severity of CED early after reperfusion therapy in stroke. Easily obtained inflammatory markers convey early warning alerts for patients at risk of severe neurological complications with an impact on long-term functional outcome. CED quantification should be included as an end point in proof-of-concept trials in immunomodulation in stroke.

Image Patch-Based Net Water Uptake and Radiomics Models Predict Malignant Cerebral Edema After Ischemic Stroke

Malignant cerebral edema (MCE) after an ischemic stroke results in a poor outcome or death. Early prediction of MCE helps to identify subjects that could benefit from a surgical decompressive craniectomy. Net water uptake (NWU) in an ischemic lesion is a predictor of MCE; however, CT perfusion and lesion segmentation are required. This paper proposes a new Image Patch-based Net Water Uptake (IP-NWU) procedure that only uses non-enhanced admission CT and does not need lesion segmentation. IP-NWU is calculated by comparing the density of ischemic and contralateral normal patches selected from the middle cerebral artery (MCA) area using standard reference images. We also compared IP-NWU with the Segmented Region-based NWU (SR-NWU) procedure in which segmented ischemic regions from follow-up CT images are overlaid onto admission images. Furthermore, IP-NWU and its combination with imaging features are used to construct predictive models of MCE with a radiomics approach. In total, 116 patients with an MCA infarction (39 with MCE and 77 without MCE) were included in the study. IP-NWU was significantly higher for patients with MCE than those without MCE (p < 0.05). IP-NWU can predict MCE with an AUC of 0.86. There was no significant difference between IP-NWU and SR-NWU, nor between their predictive efficacy for MCE. The inter-reader and interoperation agreement of IP-NWU was exceptional according to the Intraclass Correlation Coefficient (ICC) analysis (inter-reader: ICC = 0.92; interoperation: ICC = 0.95). By combining IP-NWU with imaging features through a random forest classifier, the radiomics model achieved the highest AUC (0.96). In summary, IP-NWU and radiomics models that combine IP-NWU with imaging features can precisely predict MCE using only admission non-enhanced CT images scanned within 24 h from onset.

Outcome predictors of intravenous thrombolytic therapy in acute ischemic stroke patients: an Egyptian center experiences

Background

Intravenous thrombolytic therapy remains the guideline-recommended treatment to improve outcomes after acute ischemic stroke. However, the functional outcome among patients with acute ischemic stroke after receiving intravenous thrombolytic therapy is influenced by huge variety of factors, and this was the aim of our study to evaluate the outcome predictors of intravenous thrombolytic therapy in a sample of Egyptian patients with acute ischemic stroke.

Methods

We enrolled 183 acute ischemic stroke patients who were treated with intravenous recombinant tissue plasminogen activator (IV rtPA) according to the last updated guidelines of American Heart Association and American Stroke Association (AHA/ASA) from February 2018 to February 2020; however, only 150 patients of them completed our study plan till the end. Data of study variables were collected, analyzed statistically and correlated with the functional outcome 3 months after receiving IV rtPA using the modified Rankin Scale (mRS).

Results

Good functional outcome was seen in 98 (65.3%) patients and poor functional outcome was seen in 52 (34.7%) patients. Multivariate analysis of the study variables was done to detect the significant independent predictors of the functional outcome. Atrial fibrillation (AF) (P value < 0.001*OR 6.28* (95% C.I)), hypertension (P value 0.001*OR 3.65*(95% C.I)), diabetes mellitus (DM) (P value 0.009*OR 2.805*(95% C.I)), increased National Institute of Health Stroke Scale (NIHSS) score 24 h after receiving IV rtPA (P value 0.003* OR 8.039* (95% C.I)), increased pulsatility index (PI) value in cerebral vessels at the same side of stroke lesion (P value 0.038* OR 42.48*(95% C.I)) were the significant independent predictors of poor functional outcome. On the other hand decreased NIHSS score 24 h after receiving IV rtPA (P value 0.003* OR 0.124*(95% C.I)), Normal value of PI in cerebral vessels at the same side of stroke lesion (P value 0.038* OR 42.48*(95% C.I)) were the significant independent predictors of good functional outcome.

Conclusion

Intravenous thrombolytic therapy improves the functional outcome of acute ischemic stroke patients. Also, AF, hypertension, DM, NIHSS 24 h after receiving IV rtPA and PI could be used as independent predictors of the functional outcome.

Hyperdense artery sign, symptomatic infarct swelling and effect of alteplase in acute ischaemic stroke

Background

Alteplase improves functional outcomes of patients with acute ischaemic stroke, but its effects on symptomatic infarct swelling, an adverse complication of stroke and the influence of CT hyperdense artery sign (HAS) are unclear. This substudy of the Third International Stroke Trial aimed to investigate the association between HAS and symptomatic infarct swelling and effect of intravenous alteplase on this association.

Methods

We included stroke patients whose prerandomisation scan was non-contrast CT. Raters, masked to clinical information, assessed baseline (prerandomisation) and follow-up (24–48 hours postrandomisation) CT scans for HAS, defined as an intracranial artery appearing denser than contralateral arteries. Symptomatic infarct swelling was defined as clinically significant neurological deterioration ≤7 days after stroke with radiological evidence of midline shift, effacement of basal cisterns or uncal herniation.

Results

Among 2961 patients, HAS presence at baseline was associated with higher risk of symptomatic infarct swelling (OR 2.21; 95% CI 1.42 to 3.44). Alteplase increased the risk of swelling (OR 1.69; 95% CI 1.11 to 2.57), with no difference between patients with and those without baseline HAS (p=0.49). In patients with baseline HAS, alteplase reduced the proportion with HAS at follow-up (OR 0.67; 95% CI 0.50 to 0.91), where HAS disappearance was associated with reduced risk of swelling (OR 0.25, 95% CI 0.14 to 0.47).

Conclusion

Although alteplase was associated with increased risk of symptomatic infarct swelling in patients with or without baseline HAS, it was also associated with accelerated clearance of HAS, which in return reduced swelling, providing further mechanistic insights to underpin the benefits of alteplase.

Dimethyl fumarate reduces TNF and Plasmodium falciparum induced brain endothelium activation in vitro

Background

Cerebral malaria (CM) is associated with morbidity and mortality despite the use of potent anti-malarial agents. Brain endothelial cell activation and dysfunction from oxidative and inflammatory host responses and products released by Plasmodium falciparum-infected erythrocytes (IE), are likely the major contributors to the encephalopathy, seizures, and brain swelling that are associated with CM. The development of adjunctive therapy to reduce the pathological consequences of host response pathways could improve outcomes. A potentially protective role of the nuclear factor E2-related factor 2 (NRF2) pathway, which serves as a therapeutic target in brain microvascular diseases and central nervous system (CNS) inflammatory diseases such as multiple sclerosis was tested to protect endothelial cells in an in vitro culture system subjected to tumour necrosis factor (TNF) or infected red blood cell exposure. NRF2 is a transcription factor that mediates anti-oxidant and anti-inflammatory responses.

Methods

To accurately reflect clinically relevant parasite biology a unique panel of parasite isolates derived from patients with stringently defined CM was developed. The effect of TNF and these parasite lines on primary human brain microvascular endothelial cell (HBMVEC) activation in an in vitro co-culture model was tested. HBMVEC activation was measured by cellular release of IL6 and nuclear translocation of NFκB. The transcriptional and functional effects of dimethyl fumarate (DMF), an FDA approved drug which induces the NRF2 pathway, on host and parasite induced HBMVEC activation was characterized. In addition, the effect of DMF on parasite binding to TNF stimulated HBMVEC in a semi-static binding assay was examined.

Results

Transcriptional profiling demonstrates that DMF upregulates the NRF2-Mediated Oxidative Stress Response, ErbB4 Signaling Pathway, Peroxisome Proliferator-activated Receptor (PPAR) Signaling and downregulates iNOS Signaling and the Neuroinflammation Signaling Pathway on TNF activated HBMVEC. The parasite lines derived from eight paediatric CM patients demonstrated increased binding to TNF activated HBMVEC and varied in their binding and activation of HBMVEC. Overall DMF reduced both TNF and CM derived parasite activation of HBMVEC.

Conclusions

These findings provide evidence that targeting the NRF2 pathway in TNF and parasite activated HBMVEC mediates multiple protective pathways and may represent a novel adjunctive therapy to improve infection outcomes in CM.

Drug development in targeting ion channels for brain edema

Cerebral edema is a pathological hallmark of various central nervous system (CNS) insults, including traumatic brain injury (TBI) and excitotoxic injury such as stroke. Due to the rigidity of the skull, edema-induced increase of intracranial fluid significantly complicates severe CNS injuries by raising intracranial pressure and compromising perfusion. Mortality due to cerebral edema is high. With mortality rates up to 80% in severe cases of stroke, it is the leading cause of death within the first week. Similarly, cerebral edema is devastating for patients of TBI, accounting for up to 50% mortality. Currently, the available treatments for cerebral edema include hypothermia, osmotherapy, and surgery. However, these treatments only address the symptoms and often elicit adverse side effects, potentially in part due to non-specificity. There is an urgent need to identify effective pharmacological treatments for cerebral edema. Currently, ion channels represent the third-largest target class for drug development, but their roles in cerebral edema remain ill-defined. The present review aims to provide an overview of the proposed roles of ion channels and transporters (including aquaporins, SUR1-TRPM4, chloride channels, glucose transporters, and proton-sensitive channels) in mediating cerebral edema in acute ischemic stroke and TBI. We also focus on the pharmacological inhibitors for each target and potential therapeutic strategies that may be further pursued for the treatment of cerebral edema.

A web based dynamic MANA Nomogram for predicting the malignant cerebral edema in patients with large hemispheric infarction

Background

For large hemispheric infarction (LHI), malignant cerebral edema (MCE) is a life-threatening complication with a mortality rate approaching 80%. Establishing a convenient prediction model of MCE after LHI is vital for the rapid identification of high-risk patients as well as for a better understanding of the potential mechanism underlying MCE.

Methods

One hundred forty-two consecutive patients with LHI within 24 h of onset between January 1, 2016 and August 31, 2019 were retrospectively reviewed. MCE was defined as patient death or received decompressive hemicraniectomy (DHC) with obvious mass effect (≥ 5 mm midline shift or Basal cistern effacement). Binary logistic regression was performed to identify independent predictors of MCE. Independent prognostic factors were incorporated to build a dynamic nomogram for MCE prediction.

Results

After adjusting for confounders, four independent factors were identified, including previously known atrial fibrillation (KAF), midline shift (MLS), National Institutes of Health Stroke Scale (NIHSS) and anterior cerebral artery (ACA) territory involvement. To facilitate the nomogram use for clinicians, we used the “Dynnom” package to build a dynamic MANA (acronym for MLS, ACA territory involvement, NIHSS and KAF) nomogram on web (http://www.MANA-nom.com) to calculate the exact probability of developing MCE. The MANA nomogram’s C-statistic was up to 0.887 ± 0.041 and the AUC-ROC value in this cohort was 0.887 (95%CI, 0.828 ~ 0.934).

Conclusions

Independent MCE predictors included KAF, MLS, NIHSS, and ACA territory involvement. The dynamic MANA nomogram is a convenient, practical and effective clinical decision-making tool for predicting MCE after LHI in Chinese patients.

Quantitative Serial CT Imaging-Derived Features Improve Prediction of Malignant Cerebral Edema after Ischemic Stroke

INTRODUCTION

Malignant cerebral edema develops in a small subset of patients with hemispheric strokes, precipitating deterioration and death if decompressive hemicraniectomy (DHC) is not performed in a timely manner. Predicting which stroke patients will develop malignant edema is imprecise based on clinical data alone. Head computed tomography (CT) imaging is often performed at baseline and 24-h. We determined the incremental value of incorporating imaging-derived features from serial CTs to enhance prediction of malignant edema.

METHODS

We identified hemispheric stroke patients at three sites with NIHSS ≥ 7 who had baseline as well as 24-h clinical and CT imaging data. We extracted quantitative imaging features from baseline and follow-up CTs, including CSF volume, intracranial reserve (CSF/cranial volume), as well as midline shift (MLS) and infarct-related hypodensity volume. Potentially lethal malignant edema was defined as requiring DHC or dying with MLS over 5-mm. We built machine-learning models using logistic regression first with baseline data and then adding 24-h data including reduction in CSF volume (ΔCSF). Model performance was evaluated with cross-validation using metrics of recall (sensitivity), precision (predictive value), as well as area under receiver-operating-characteristic and precision-recall curves (AUROC, AUPRC).

RESULTS

Twenty of 361 patients (6%) died or underwent DHC. Baseline clinical variables alone had recall of 60% with low precision (7%), AUROC 0.59, AUPRC 0.15. Adding baseline intracranial reserve improved recall to 80% and AUROC to 0.82 but precision remained only 16% (AUPRC 0.28). Incorporating ΔCSF improved AUPRC to 0.53 (AUROC 0.91) while all imaging features further improved prediction (recall 90%, precision 38%, AUROC 0.96, AUPRC 0.66).

CONCLUSION

Incorporating quantitative CT-based imaging features from baseline and 24-h CT enhances identification of patients with malignant edema needing DHC. Further refinements and external validation of such imaging-based machine-learning models are required.

A Nomogram Model to Predict Malignant Cerebral Edema in Ischemic Stroke Patients Treated with Endovascular Thrombectomy: An Observational Study

PURPOSE

Malignant cerebral edema (MCE) in patients undergoing endovascular thrombectomy (EVT) is not uncommon and can reduce the benefit of EVT. We aimed to develop a nomogram model to predict the risk of MCE in ischemic stroke patients after EVT.

PATIENTS AND METHODS

We retrospectively collected patients treated with EVT caused by anterior circulation large vessel occlusion stroke at two comprehensive stroke centers. MCE was defined as midline shift >5 mm at the septum pellucidum or pineal gland with obliteration of the basal cisterns or the need for early decompressive hemicraniectomy. A multivariate logistic model was utilized to construct the best-fit nomogram model. The discrimination and calibration of the nomogram were estimated using the area under the receiver operating characteristic curve (AUC-ROC) and Hosmer-Lemeshow test.

RESULTS

A total of 370 patients (mean age, 67.2±11.9 years; male, 56.8%) were enrolled in the final analysis. Among them, 71 (19.2%) patients experienced MCE after EVT treatment. After adjustment for potential confounders, age, baseline National Institutes of Health Stroke Scale score, collateral circulation, fast blood glucose level and recanalization were independent predictors of MCE and were incorporated into the nomogram. The AUC-ROC value of the nomogram was 0.805 (95% confidence interval [CI]: 0.750-0.860). The Hosmer-Lemeshow goodness-of-fit test showed good calibration of the nomogram (P = 0.681).

CONCLUSION

The nomogram composed of age, baseline National Institutes of Health Stroke Scale score, blood glucose level, collateral circulation and recanalization may predict the probability of MCE in anterior circulation large vessel occlusion stroke patients treated with EVT.

Effect of Recanalization on Cerebral Edema in Ischemic Stroke Treated With Thrombolysis and/or Endovascular Therapy

Background and Purpose- A large infarct and expanding cerebral edema (CED) due to a middle cerebral artery occlusion confers a 70% mortality unless treated surgically. Reperfusion may cause blood-brain barrier disruption and a risk for cerebral edema and secondary parenchymal hemorrhage (PH). We aimed to investigate the effect of recanalization on development of early CED and PH after recanalization therapy. Methods- From the SITS-International Stroke Treatment Registry, we selected patients with signs of artery occlusion at baseline (either Hyperdense Artery Sign or computed tomography/magnetic resonance imaging angiographic occlusion). We defined recanalization as the disappearance of radiological signs of occlusion at 22 to 36 hours. Primary outcome was moderate to severe CED and secondary outcome was PH on 22- to 36-hour imaging scans. We used logistic regression with adjustment for baseline variables and PH. Results- Twenty two thousand one hundred eighty-four patients fulfilled the inclusion criteria (n=18 318 received intravenous thrombolysis, n=3071 received intravenous thrombolysis+thrombectomy, n=795 received thrombectomy). Recanalization occurred in 64.1%. Median age was 71 versus 71 years and National Institutes of Health Stroke Scale score 15 versus 16 in the recanalized versus nonrecanalized patients respectively. Recanalized patients had a lower risk for CED (13.0% versus 23.6%), adjusted odds ratio (aOR), 0.52 (95% CI, 0.46-0.59), and a higher risk for PH (8.9% versus 6.5%), adjusted odds ratio, 1.37 (95% CI, 1.22-1.55), than nonrecanalized patients. Conclusions- In patients with acute ischemic stroke, recanalization was associated with a lower risk for early CED even after adjustment for higher rate for PH in recanalized patients.

Elevated blood glucose is associated with aggravated brain edema in acute stroke

BACKGROUND AND PURPOSE

Clinical outcome after endovascular thrombectomy in patients with acute ischemic stroke still varies significantly. Higher blood glucose levels (BGL) have been associated with worse clinical outcome, but the pathophysiological causes are not yet understood. We hypothesized that higher levels of BGL are associated with more pronounced ischemic brain edema and worse clinical outcome mediated by cerebral collateral circulation.

METHODS

178 acute ischemic stroke patients who underwent mechanical thrombectomy were included. Early ischemic brain edema was determined using quantitative lesion water uptake on initial computed tomography (CT) and collateral status was assessed with an established 5-point scoring system in CT-angiography. Good clinical outcome was defined as functional independence (modified Rankin Scale [mRS] score 0-2). Multivariable logistic regression analysis was performed to predict functional independence and linear regression analyses to investigate the impact of BGL and collateral status on water uptake.

RESULTS

The mean BGL at admission was significantly lower in patients with good outcome at 90 days (116.5 versus 138.5 mg/dl; p < 0.001) and early water uptake was lower (6.3% versus 9.6%; p < 0.001). The likelihood for good outcome declined with increasing BGL (odds ratio [OR] per 100 mg/dl BGL increase: 0.15; 95% CI 0.02-0.86; p = 0.039). Worse collaterals (1% water uptake per point, 95% CI 0.4-1.7%) and higher BGL (0.6% per 10 mg/dl BGL, 95% CI 0.3-0.8%) were significantly associated with increased water uptake.

CONCLUSION

Elevated admission BGL were associated with increased early brain edema and poor clinical outcome mediated by collateral status. Patients with higher BGL might be targeted by adjuvant anti-edematous treatment.

Circulating Aquaporin-4 as A biomarker of early neurological improvement in stroke patients: A pilot study

Patients' outcome prediction after ischemic stroke is still challenging. Aquaporin-4 (AQP4) is a water channel that is up-regulated in the brain after the ischemic event, but its presence in bloodstream of stroke patients has not been previously studied. The aim of this pilot study was to investigate circulating AQP4 levels after stroke and its correlation with infarct growth and neurological outcome. AQP4 level was determined by ELISA in serum from 42 t-PA-treated ischemic stroke patients at admission (before t-PA) and 13 healthy subjects. To assess infarct growth, serial brain diffusion-weighted magnetic resonance images were performed at hospital admission and 1-3 days after. Neurological improvement was defined as a ≥4-point decrease in NIHSS score compared to baseline score. Despite stroke patients and healthy controls had similar baseline circulating AQP4 levels, among strokes AQP4 level negatively correlated with NIHSS score at admission (R= -0.34, p = 0.029) and with infarct growth after 1-3 days of stroke onset (R=-0.36; p = 0.018). Furthermore, baseline AQP4 level was higher in those stroke patients showing a neurological improvement 48 h after stroke onset (p = 0.030) and at hospital discharge (p = 0.037). Baseline AQP4 levels also resulted to be an independent predictor of good neurological outcome at both studied time points (OR_adj: 14.33[1.82-112.92], p = 0.012 at 48 h; OR_adj: 4.86[0.98-24.12], p = 0.053 at discharge) in logistic regression analysis, adjusted by age, sex, baseline NIHSS and significant variables in the univariate analysis. Overall, we have explored circulating AQP4 levels, and our data suggest that AQP4 could be used as a biomarker of neurological recovery in the acute-subacute phase of ischemic stroke.