Imaging Cerebral Microhemorrhages in Military Service Members with Chronic Traumatic Brain Injury

Abstract

Purpose-To detect cerebral microhemorrhages in military service members with chronic traumatic brain injury by using susceptibility-weighted magnetic resonance (MR) imaging. The longitudinal evolution of microhemorrhages was monitored in a subset of patients by using quantitative susceptibility mapping.Materials and Methods-The study was approved by the Walter Reed National Military Medical Center institutional review board and is compliant with HIPAA guidelines. All participants underwent two-dimensional conventional gradient-recalled-echo MR imaging and three-dimensional flow-compensated multi-echo gradient-recalled-echo MR imaging (processed to generate susceptibility-weighted images and quantitative susceptibility maps), and a subset of patients underwent follow-up imaging. Microhemorrhages were identified by two radiologists independently. Comparisons of microhemorrhage number, size, and magnetic susceptibility Address correspondence to: G.R. (gerard.p.riedy.civ@mail.mil). The views expressed in this manuscript are those of the authors and do not reflect the official policy of the U.S. Departments of the Army, Navy, or Air Force; U.S. Department of Defense; or U.S. Government. Author contributions:Guarantors of integrity of entire study, W.L., G.R.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; approval of final version of submitted manuscript, all authors; agrees to ensure any questions related to the work are appropriately resolved, all authors; literature research, W.L., T.L., G.R.; clinical studies, W.L., K.S., J.S.S., P.H.Y., E.B.S., G.R.; experimental studies, W.L., K.S., T.L., Y.W., T.R.O., G.R.; statistical analysis, W.L., D.J., J.O., T.R.O.; and manuscript editing, W.L., K.S., P.H.Y., J.O., E.B.S., Y.W., T.R.O., G.R.Disclosures of Conflicts of Interest: W.L. disclosed no relevant relationships. K.S. disclosed no relevant relationships. J.S.S. disclosed no relevant relationships. D.J. disclosed no relevant relationships. P.H.Y. disclosed no relevant relationships. J.O. disclosed no relevant relationships. E.B.S. disclosed no relevant relationships. T.L. Activities related to the present article: disclosed no relevant relationships. Activities not related to the present article: author received payment from MedImageMetric; author has a QSM patent. Other relationships: disclosed no relevant relationships. Y.W. Activities related to the present article: disclosed no relevant relationships. Activities not related to the present article: disclosed no relevant relationships. Other relationships: author has a QSM patent. T.R.O. disclosed no relevant relationships. G.R. disclosed no relevant relationships.Online supplemental material is available for this article.To order printed copies, contact reprints@rsna.org HHS Public Access Author ManuscriptAuthor Manuscript Author ManuscriptAuthor Manuscript derived from quantitative susceptibility maps between baseline...

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