NEURORADIOLOGYHead Ultrasound Resistive Indices Are Associated With Brain Injury on Diffusion Tensor Imaging Magnetic Resonance Imaging in Neonates With Hypoxic-Ischemic EncephalopathySnyder, Elizabeth J. MD∗; Perin, Jamie PhD†; Chavez-Valdez, Raul MD‡; Northington, Frances J. MD‡; Lee, Jennifer K. MD§; Tekes, Aylin MD∥Author Information From the ∗Department of Radiology, Johns Hopkins Hospital, Baltimore, MD †Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD ‡Department of Pediatrics, Division of Neonatology, JHU, Baltimore, MD; and Neurosciences Intensive Care Nursery, Johns Hopkins Hospital, Baltimore, MD §Department of Anesthesiology and Critical Care Medicine, Division of Pediatric Anesthesiology, Johns Hopkins Hospital, Baltimore, MD ∥Department of Radiology, Division of Pediatric Radiology and Pediatric Neuroradiology, Johns Hopkins Hospital, Baltimore, MD. Received for publication March 24, 2020; accepted May 20, 2020. Correspondence to: Elizabeth J. Snyder, MD, Department of Pediatric Radiology, Monroe Carell, Jr. Children's, Hospital at Vanderbilt, 2200 Children's Way Ste 1415, Nashville, TN 37232 (e-mail: Elizabeth.firstname.lastname@example.org). Present address (E.J.S.): Department of Pediatric Radiology, Monroe Carell, Jr. Children's Hospital at Vanderbilt, Nashville, TN. The JHU-SOM Clinician Scientist Award, The Sutland-Pakula Endowment for Neonatal Research provided funding for authors F.J.N. (RO1HD070996, RO1HD086058, R21AG061643), A.T.B. (RO1HD086058), and R.C.V. (KO8NS096115, 3K08NS096115-03S1). The authors declare no conflicts of interest. Journal of Computer Assisted Tomography: 9/10 2020 - Volume 44 - Issue 5 - p 687-691 doi: 10.1097/RCT.0000000000001069 Buy Metrics Abstract Background Neonatal hypoxic-ischemic encephalopathy (HIE) is associated with dysfunctional cerebral autoregulation. Resistive index (RI) measured in the anterior cerebral artery on transfontanellar head ultrasound is a noninvasive measure of blood flow and may indicate autoregulation dysfunction. We tested whether RI was associated with brain injury on diffusion tensor imaging magnetic resonance imaging (MRI). Materials and Methods Seventy-five neonates who underwent therapeutic hypothermia for HIE were enrolled. Resistive index values were obtained from head ultrasound performed at the end of therapeutic hypothermia. Apparent diffusion coefficient scalars were measured on MRIs performed before day of life 10. Results Lower RI was associated with lower apparent diffusion coefficient in the centrum semiovale, basal ganglia, thalamus, and posterior limb of the internal capsule. Combining RI and Apgar scores improved the ability to distinguish injury severity on MRI relative to either metric alone. Conclusions Low RI correlated with worse brain injury on diffusion tensor imaging and may serve as an early marker of brain injury in cooled HIE neonates. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.