© 2015. The copyright of this document resides with its authors. It may be distributed unchanged freely in print or electronic forms. VIKSNE ET AL.: TEXTURAL ANALYSIS ON R.O.I.s TO STUDY DISEASE 1 Abstract We propose a framework for investigating the properties of apparently normal tissues on brain structural magnetic resonance images of patients with small vessel disease (SVD). It involves the extraction of textural features in regions of interest (ROIs) obtained from an anatomically-relevant template, combined with a statistical analysis that considers the relative distribution of SVD markers (e.g. microbleeds, perivascular spaces and white matter hyperintensities) with respect to the ROIs’ textural characteristics in arterial territories derived from another template. We apply this approach to data from 42 patients from a study of mild stroke to investigate whether or not normal tissues in different brain regions are homogeneous regardless of the presence of specific SVD markers and varieties in the manifestations of the pathology (stroke lesion in different arterial territories). Our results suggest that this is not the case: that normal tissues are heterogeneous and that local variations (represented by the entropy) are associated with SVD markers, in agreement with clinical reports. 1 Introduction Stroke is the second largest cause of death worldwide and the commonest cause of disability in adulthood[1]. The lifetime risk of stroke in middle-aged men is 1 in 6, and even higher for women[2]. Magnetic Resonance Imaging (MRI) has become essential in Textural Characterisation on Regions of Interest: A Useful Tool for the Study of Small Vessel Disease Linda Viksne 1 s1007729@sms.ed.ac.uk Maria del C. Valdés Hernández 2 * M.Valdes-Hernan@ed.ac.uk Katie Hoban 1 s0900915@sms.ed.ac.uk Anna K. Heye 2 s1263127@sms.ed.ac.uk Victor Gonzalez-Castro 2 victor.gonzalez@ed.ac.uk Joanna M. Wardlaw 2 Joanna.Wardlaw@ed.ac.uk 1 College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK 2 Department of Neuroimaging Sciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK * Corresponding author