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Abstract: Although stroke is a leading cause of disability, the quantitative relationship between baseline clinical and imaging characteristics and long‐term disability outcomes has rarely been studied. Prospectively collected clinical data from 405 patients with acute ischemic stroke including brain magnetic resonance images (MRIs) and disability outcomes assessed using the modified Rankin Scale (mRS) 3 month after the onset of disease were analyzed using a proportional odds cumulative logit model implemented in NONMEM. The relationship between the difference in lesion volume (DLV) — lesion volume measured by brain MRI 5 days later — lesion volume at the onset of the disease, and the mRS measured at 3 months (mRS3) was modeled first, and the potential covariates were tested. The Emax model best described the relationship between DLV and the logit probability of each mRS3. DLV, baseline stroke severity, age, and diabetes mellitus were identified as significant predictors of the probabilities of mRS3. The quantitative model constructed in the current analysis will enable us to predict the long‐term disabilities of the patients with acute ischemic stroke using the patient‐specific MRI and other clinical information, which will be useful for individualizing therapies and for making the clinical development of a novel drug more efficient. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether fast scanned MRI using a 1.5-T scanner is a reliable method for the detection and characterization of acute ischemic stroke in comparison with conventional MRI.Methods: From May 2015 to June 2016, 862 patients (FLAIR, n = 482; GRE, n = 380; MRA, n = 190) were prospectively enrolled in the study, with informed consent and under institutional review board approval. The patients underwent both fast (EPI-FLAIR, ETL-FLAIR, TR-FLAIR, EPI-GRE, parallel-GRE, fast CE-MRA) and conventional MRI (FLAIR, GRE, time-of-flight MRA, fast CE-MRA). Two neuroradiologists independently assessed agreements in acute and chronic ischemic hyperintensity, hyperintense vessels (FLAIR), microbleeds, susceptibility vessel signs, hemorrhagic transformation (GRE), stenosis (MRA), and image quality (all MRI), between fast and conventional MRI. Agreements between fast and conventional MRI were evaluated by generalized estimating equations. Z-scores were used for comparisons of the percentage agreement among fast FLAIR sequences and fast GRE sequences and between conventional and fast MRA.Results: Agreements of more than 80% were achieved between fast and conventional MRI (ETL-FLAIR, 96%; TR-FLAIR, 97%; EPI-GRE, 96%; parallel-GRE, 98%; fast CE-MRA, 86%). ETL- and TR-FLAIR were significantly superior to EPI-FLAIR in the detection of acute ischemic hyperintensity and hyperintense vessels, while parallel-GRE was significantly superior to EPI-GRE in the detection of susceptibility vessel sign (p value < 0.05 for all). There were no significant differences in the other scores and image qualities (p value > 0.05).Conclusions: Fast MRI at 1.5 T is a reliable method for the detection and characterization of acute ischemic stroke in comparison with conventional MRI.Key Points: • Fast MRI at 1.5 T may achieve a high intermethod reliability in the detection and characterization of acute ischemic stroke with a reduction in scan time in comparison with conventional MRI. [ABSTRACT FROM AUTHOR]