Kristin M James PhD, Presenter: Employee, Acuitas Medical

Timothy W. James PhD, Abstract Co-Author: Founder, Acuitas Medical Ltd

Steven Chance DPhil, Abstract Co-Author: Nothing to Disclose

Lance Farr MS, Abstract Co-Author: Nothing to Disclose

James Rafferty PhD, Abstract Co-Author: Nothing to Disclose

David Chase MS, Abstract Co-Author: Nothing to Disclose

Michael Brady, Abstract Co-Author: Shareholder, Matakina International Limited Shareholder, Mirada Medical Ltd

Gareth Thomas MSc, Abstract Co-Author: Nothing to Disclose

Peter Jezzard PhD, Abstract Co-Author: Consultant, Acuitas Medical Ltd

Christopher Rodgers DPhil, Abstract Co-Author: Consultant, Acuitas Medical Ltd

Robert Harbaugh MD, Abstract Co-Author: Nothing to Disclose

Scott Grafton PhD, Abstract Co-Author: Nothing to Disclose

To assess the capability of fineSA, a new magnetic resonance-based technique for quantifying biologic textures too fine to be resolved by conventional MR imaging. Our aim is to demonstrate its efficacy as a monitor for the cortical textural changes linked to ageing and AD.

Using a small RF coil positioned directly against the subject's forehead, 1D, spatially-encoded MR echoes, sampled at 20 microns, were acquired along the long axis of a prismatic volume, 1 x 3 x 32mm, positioned within Brodmann area 9 in the human prefrontal cortex.  Analyses of the resulting signal intensity profile yield a spectrum of textural wavelengths present within the sampled volume of brain tissue. Signal averaging over 200 echoes in the complex domain provides significant noise reduction and a measure of the statistical significance of the spectral features.

Based on a cohort of 16 subjects, ranging in age from 21 years to 80 years, we have 1) demonstrated the ability of the fineSA technique to repeatably resolve sub 100-micron in the human prefrontal cortex, and 2) shown both age and cognitive impairment-related textural changes in the prefrontal cortex using this technique. We hypothesize that the loss of texture near 95 microns in the cognitively compromised subjects is a signature of loss of order in the neuronal columns that span the mid layers of the neocortex; prior histology-based studies have shown AD-related upset to these structures. Sampling of the cortex was done with the long axis of the prismatic volume running normal to the axes of these columnar structures. In healthy brain these columns are well ordered and have a spacing of approximately 80-100 microns.

fineSA provides a sensitive indication of textural change within the human prefrontal cortex. Our initial results indicate that this assessment technique is capable of monitoring age and cognitive impairment-related tissue changes.

Understanding cause, quantifying risk, and monitoring progression of Alzheimer's disease is currently the greatest unmet need in clinical neurology, especially given the rapidy aging population.

James, K, James, T, Chance, S, Farr, L, Rafferty, J, Chase, D, Brady, M, Thomas, G, Jezzard, P, Rodgers, C, Harbaugh, R, Grafton, S, A New MR-based High-sensitivity Quantitative Measure of Fine Cortical Texture Changes Associated with AD Onset and Progression: In Vivo Resolution of Sub 100-Micron Texture in Prefrontal Cortex.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12027449.html