Noninvasive Cerebral Perfusion Imaging in High-Risk Neonates

Abstract

Advances in medical and surgical care of the high-risk neonate have led to increased survival. A significant number of these neonates suffer from neurodevelopmental delays and failure in school. The focus of clinical research has shifted to understanding events contributing to neurological morbidity in these patients. Assessing changes in cerebral oxygenation and regulation of cerebral blood flow (CBF) is important in evaluating the status of the central nervous system. Traditional CBF imaging methods fail for both ethical and logistical reasons. Optical near infrared spectroscopy (NIRS) is increasingly being used for bedside monitoring of cerebral oxygenation and blood volume in both very low birth weight infants and neonates with congenital heart disease. Although trends in CBF may be inferred from changes in cerebral oxygenation and/or blood volume, NIRS does not allow a direct measure of CBF in these populations. Two relatively new modalities, arterial spinlabeled perfusion magnetic resonance imaging and optical diffuse correlation spectroscopy, provide direct, noninvasive measures of cerebral perfusion suitable for the high-risk neonates. Herein we discuss the instrumentation, applications, and limitations of these noninvasive imaging techniques for measuring and/or monitoring CBF. Keywordsinfant cerebral blood flow; CBF; arterial spin labeled perfusion; MRI; PVL; optical spectroscopy Advances in medical and surgical management have led to increase in survival among infants with severe conditions, including prematurity, birth trauma, and congenital malformations (congenital heart defects and congenital diaphragmatic hernia, among others). Minimizing factors that contribute to neurological morbidity prove to be a significant challenge facing physicians in the routine care of neonates with these conditions. Improving our ability to assess changes in cerebral oxygenation and regulation of cerebral blood flow (CBF) will enhance our Address reprint requests to Daniel J. Licht, MD, Department of Neurology, Children's Hospital of Philadelphia, 34th and Civic Centre Blvd, Philadelphia, PA 19104. licht@email.chop.edu. Publisher's Disclaimer: This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright NIH Public Access understanding of how these changes may contribute toward acquired brain injury in its various forms, including hypoxia-ischemic injury, periventricular l...

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