title: Mental speed is associated with the shape irregularity of white matter MRI hyperintensity load.
abstract: Brain MRI white matter hyperintensities (WMHs) are common in elderly subjects. Their impact on cognition, however, appears highly variable. Complementing conventional scoring of WMH load (volume and location) by quantitative characterization of the shape irregularity of WMHs might improve the understanding of the relationship between WMH load and cognitive performance. Here we propose the "confluency sum score" (COSU) as a marker of the total shape irregularity of WMHs in the brain. The study included two independent patient samples: 87 cognitively impaired geriatric inpatients from a prospective neuroimaging study (iDSS) and 198 subjects from the National Alzheimer's Coordinating Center (NACC) database (132 with, 66 w/o cognitive impairment). After automatic segmentation and clustering of the WMHs on FLAIR (LST toolbox, SPM8), the confluency of the i-th contiguous WMH cluster was computed as confluencyi= [1/(36π)∙surfacei3/volumei2]1/3-1. The COSU was obtained by summing the confluency over all WMH clusters. COSU was tested for correlation with CERAD-plus subscores. Correlation analysis was restricted to subjects with at least moderate WMH load (≥ 13.5 ml; iDSS / NACC: n = 52 / 80). In the iDSS sample, among the 12 CERAD-plus subtests the trail making test A (TMT-A) was most strongly correlated with the COSU (Spearman rho = -0.345, p = 0.027). TMT-A performance was not associated with total WMH volume (rho = 0.147, p = 0.358). This finding was confirmed in the NACC sample (rho = -0.261, p = 0.023 versus rho = -0.040, p = 0.732). Cognitive performance in specific domains including mental speed and fluid abilities seems to be more strongly associated with the shape irregularity of white matter MRI hyperintensities than with their volume.
authors: Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.|School of Mathematics and Natural Science, University of Wuppertal, Wuppertal, Germany.
authors: Catharina
authors: C
authors: Lange
authors: Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.|jung diagnostics GmbH, Hamburg, Germany.
authors: Per
authors: P
authors: Suppa
authors: Evangelisches Geriatriezentrum Berlin, Berlin, Germany.
authors: Anja
authors: A
authors: Mäurer
authors: Berlin Center for Advanced Neuroimaging, Bernstein Center for Computational Neuroscience, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: Kerstin
authors: K
authors: Ritter
authors: School of Mathematics and Natural Science, University of Wuppertal, Wuppertal, Germany.|Institute of Neuroscience and Medicine, Forschungszentrum Jülich, Jülich, Germany.
authors: Uwe
authors: U
authors: Pietrzyk
authors: Lipid Clinic at the Interdisciplinary Metabolism Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: Elisabeth
authors: E
authors: Steinhagen-Thiessen
authors: Center for Stroke Research Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: Jochen B
authors: JB
authors: Fiebach
authors: jung diagnostics GmbH, Hamburg, Germany.
authors: Lothar
authors: L
authors: Spies
authors: Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany. ralph.buchert@charite.de.
authors: Ralph
authors: R
authors: Buchert
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging* / Q000473:pathology / Q000523:psychology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008606:Mental Processes; D059906:Neuroimaging; D009483:Neuropsychological Tests; D010363:Pattern Recognition, Automated; D011446:Prospective Studies; D012189:Retrospective Studies; D066127:White Matter / Q000000981:diagnostic imaging* / Q000473:pathology
keywords: Biomarker; CERAD; Cerebrovascular disease; Confluency; FLAIR; MRI; White matter hyperintensities