Background and Objective
There is no consensus about apparent diffusion coefficient (ADC) values in acute stroke
regions that could be used by clinicians in a day-to-day clinical practice; regional
measures using confidence intervals (CIs) and a graphic representation of means are
scarce in the literature. Our aim in this study was to compare ADC values in infarct,
penumbra, and normal brain regions in patients with acute ischemic stroke (AIS).
Methods
This is a retrospective study of 100 magnetic resonance imaging data sets from AIS
patients. ADC values were measured in the infarct, penumbra, and normal regions. Three
hundred measurements underwent 1-way analysis of variance, analysis of means, and
calculation of 95% and 84% CIs.
Results
There was a statistically significant difference at the P level less than .025 in ADC values for the 3 regions (F[2, 297] = 168.039, P ≤ .001), with no overlap of the CIs for the means among the regions: normal brain
(mean [M] = .847, standard deviation [SD] = .103, 95% CI: .825-.866), infarct (M = .533, SD = .157, 95% CI: .501-.563), and penumbra (M = .764, SD = .110, 95% CI: .740-.787).
Conclusions
ADC values might be used as reference data in acute stroke-specific populations; CIs
would provide radiologists and clinicians with additional quantitative tools to evaluate
penumbra, infarct, and normal brain tissue and to tailor follow-up and treatment options
for selected patients.
Key Words
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Article info
Publication history
Published online: November 30, 2015
Accepted:
October 31,
2015
Received in revised form:
August 20,
2015
Received:
April 2,
2015
Footnotes
This study was supported in part by the Medica Sur Clinic and Foundation.
Mariana Lopez-Mejia, MD, was enrolled as a research fellow at the MRI unit of Medica Sur Clinic and Foundation from 2013 to 2014. Ernesto Roldan-Valadez was Coordinator of Research at the MRI Unit of Medica Sur Clinic and Foundation from 2010 to April 2015.
Current address: Faculty of Health Sciences, Panamerican University. Donatello 59, Col. Insurgentes Mixcoac, Del. Benito Juarez, Mexico City CP 03920, Mexico. Office phone/Fax: +(52-55) 5482 1600 Ext. 5695.
Identification
DOI: https://doi.org/10.1016/j.jstrokecerebrovasdis.2015.10.033
Copyright
© 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.
