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Ischemic stroke poses a significant global health challenge, necessitating ongoing exploration of its pathophysiology and treatment strategies. This comprehensive review integrates various aspects of ischemic stroke research, emphasizing crucial mechanisms, therapeutic approaches, and the role of clinical imaging in disease management. It discusses the multifaceted role of Netrin-1, highlighting its potential in promoting neurovascular repair and mitigating post-stroke neurological decline. It also examines the impact of blood–brain barrier permeability on stroke outcomes and explores alternative therapeutic targets such as statins and sphingosine-1-phosphate signaling. Neurocardiology investigations underscore the contribution of cardiac factors to post-stroke mortality, emphasizing the importance of understanding the brain–heart axis for targeted interventions. Additionally, the review advocates for early reperfusion and neuroprotective agents to counter-time-dependent excitotoxicity and inflammation, aiming to preserve tissue viability. Advanced imaging techniques, including DWI, PI, and MR angiography, are discussed for their role in evaluating ischemic penumbra evolution and guiding therapeutic decisions. By integrating molecular insights with imaging modalities, this interdisciplinary approach enhances our understanding of ischemic stroke and offers promising avenues for future research and clinical interventions to improve patient outcomes. [ABSTRACT FROM AUTHOR]

Background and Purpose: In large vessel occlusion (LVO) stroke patients, relative cerebral blood flow (rCBF)<30% volume thresholds are commonly used in treatment decisions. In the early time window, nearly infarcted but salvageable tissue volumes may lead to pretreatment overestimates of infarct volume, and thus potentially exclude patients who may otherwise benefit from intervention. Our multisite analysis aims to explore the strength of relationships between widely used pretreatment CT parameters and clinical outcomes for early window stroke patients. Methods: Patients from two sites in a prospective registry were analyzed. Patients with LVOs, presenting within 3 hours of last known well, and who were successfully reperfused were included. Primary short‐term neurological outcome was percent National Institutes of Health Stroke Scale (NIHSS) change from admission to discharge. Secondary long‐term outcome was 90‐day modified Rankin score. Spearman's correlations were performed. Significance was attributed to p‐value ≤.05. Results: Among 73 patients, median age was 66 (interquartile range 54‐76) years. Among all pretreatment imaging parameters, rCBF<30%, rCBF<34%, and rCBF<38% volumes were significantly, inversely correlated with percentage NIHSS change (p<.048). No other parameters significantly correlated with outcomes. Conclusions: Our multisite analysis shows that favorable short‐term neurological recovery was significantly correlated with rCBF volumes in the early time window. However, modest strength of correlations provides supportive evidence that the applicability of general ischemic core estimate thresholds in this subpopulation is limited. Our results support future larger‐scale efforts to liberalize or reevaluate current rCBF parameter thresholds guiding treatment decisions for early time window stroke patients. [ABSTRACT FROM AUTHOR]

Background and Purpose: Acute ischemic stroke due to large vessel occlusion (AIS‐LVO) is a major cause of functional dependence. Collateral status (CS) is an important determinant of functional outcomes. Pretreatment CT perfusion (CTP) parameters serve as reliable surrogates of CS. Penumbra Salvage Index (PSI) is another parameter predictive of functional outcomes in AIS‐LVO. The aim of this study is to assess the relationship of pretreatment CTP parameters with PSI. Methods: In this prospectively collected, retrospectively reviewed multicenter analysis, inclusion criteria were as follows: (1) CT angiography confirmed middle cerebral artery (MCA) M1‐segment and proximal M2‐segment occlusion from 9/1/2017 to 9/22/2022; (2) diagnostic CTP; and (3) available diagnostic Magnetic resonance Imaging (MRI) diffusion‐weighted images. Pearson correlation analysis was performed to assess the association between cerebral blood volume (CBV) index and hypoperfusion intensity ratio (HIR) with PSI. p value ≤.05 was considered statistically significant. Results: In total, 131 patients (n = 86, M1 and n = 45, proximal M2 occlusion) met our inclusion criteria. CBV index showed a modest positive correlation with PSI (r = 0.34, p<.001) in patients with proximal MCA occlusion. Similar trends were noted in subgroup analysis of patients with M1 occlusion, and proximal M2 occlusion. Whereas, HIR did not have a strong trend or correlation with PSI. Conclusion: CBV index correlates with PSI, whereas HIR does not. Future studies are needed to expand our understanding of the adjunct role of CBV index with other similar pretreatment CTP‐based markers in clinical evaluation and decision‐making in patients with MCA occlusion. [ABSTRACT FROM AUTHOR]

3D time-of-flight (TOF) MR angiography (MRA) benefits from ultra-high-field MRI (≥7 T) due to improved contrast and increased signal-to-noise ratio. However, high-resolution TOF MRA at 7T usually requires longer acquisition times. In addition, relatively higher specific absorption rate (SAR) at 7T limits the choice of optimal pulse sequence parameters, especially if venous saturation is employed. Here, we illustrate the clinical application of ultra-high resolution cerebral 7T TOF MRA using compressed sensing in cases of artery of Percheron and lacunar infarcts, which showed superior resolution and exquisite details pertinent to the clinical diagnosis. The technical challenges associated with high-resolution 7T imaging were alleviated by optimization of sequence parameters and utilization of compressed sensing acceleration. [ABSTRACT FROM AUTHOR]

Pretreatment CT perfusion (CTP) marker relative cerebral blood volume (rCBV) < 42% lesion volume has recently shown to predict poor collateral status and poor 90-day functional outcome. However, there is a paucity of studies assessing its association with hemorrhagic transformation (HT). Here, we aim to assess the relationship between rCBV < 42% lesion volume with HT.In this retrospective study, we included patients with acute ischemic stroke secondary to large vessel occlusion (AIS-LVO) of anterior circulation who had successful recanalization from two comprehensive stroke centers between 9/1/2017 and 10/01/2023. Successful recanalization was defined as modified treatment in cerebral infarction (mTICI) 2b or greater. Logistic regression analysis and ROC analysis were used to assess the relationship between rCBV <42% and HT.In total, 150 patients (median age: 69 years, 58.7% female) met our inclusion criteria. On multivariable logistic regression analysis, taking into account age, sex, hypertension, hyperlipidemia, diabetes, prior stroke or transient ischemic attack, admission National Institute of Health stroke scale (NIHSS), Alberta Stroke Program Early CT Score (ASPECTS), and intravenous thrombolysis, rCBV <34% (aOR:1.01, P < .05), rCBV <38% (aOR:1.01, P < .05) and rCBV <42% (aOR:1.01, P < .05) lesion volumes were independently associated with HT. On ROC analysis rCBV < 42% (AUC = 0.61, P < .05) performed slightly better than rCBV < 38% (AUC = 0.59, P < .05) and rCBV < 34% (AUC = 0.59, P < .05) in predicting HT.The rCBV <42% lesion volume is independently associated with HT in AIS-LVO patients who underwent successful recanalization. [ABSTRACT FROM AUTHOR]