Abstract TMP38: Diminished Cortical Thickness and Increased Oxygen Extraction Fraction in Moyamoya Disease
PURPOSE: Chronic hemodynamic impairment may lead to reduced cortical thickness, perhaps related to metabolic down-regulation in cortical neurons. The purpose of this study was to determine whether hemodynamic impairment correlated with diminished cortical thickness in patients with idiopathic moyamoya phenomenon.
METHODS: The study was a retrospective analysis of a prospective, blindly-adjudicated, multicenter patient cohort. Inclusion criteria required moyamoya phenomenon diagnosed by catheter angiography and presumed idiopathic basal arterial occlusive disease. Oxygen extraction fraction (OEF) was measured using positron emission tomography (PET). Hemodynamic impairment was determined by comparing the OEF of middle cerebral artery territories to cerebellar regions and to normal control subjects. MR imaging was obtained concurrently with PET, within several hours, and cortical thickness estimates were made with Freesurfer (http://surfer.nmr.mgh.harvard.edu). OEF measurements were then compared to cortical thickness measurements.
RESULTS: Adequate MR studies were available for 40 subjects. Mean age was 44 years. Eleven were male. Thirty-one had bilateral disease. Three had increased OEF in both hemispheres and four had unilateral increased OEF. Three patients underwent revascularization surgery during follow-up. Robust linear regression of relative cortical thickness to relative OEF is shown below: the slope was -0.02693 (-0.03002, -0.02384), the intercept was 1.022 (1.019, 1.025) at 95% confidence. Pearson’s R-square was 0.9648.
CONCLUSIONS: Chronic hemodynamic impairment may be associated with reduced cortical thickness. This may reflect reversible down-regulation or irreversible subclinical ischemic injury. Supported by NINDS RO1 NS051631, 1 UL1 RR024992-01, 1 TL1 RR024995-01 and 1 KL2 RR 024994-01 from the National Center for Research Resources (NCRR).
- © 2012 by American Heart Association, Inc.