title: Calculation of apparent diffusion coefficients (ADCs) in brain using two-point and six-point methods.
abstract: We evaluated the relative accuracy of calculating apparent diffusion coefficients (ADCs) of intracranial tissues using a two-point versus a six-point regression technique. Echo planar diffusion-weighted MRI was performed at 1.5 T in three standard locations and in pathologic regions in 10 subjects using gradient strengths corresponding to b values of 1, 100, 200, 500, 800, and 1,000 s/mm2. Estimation of ADCs was made using two methods: a nonlinear regression model using measurements from the full set of b values (six-point technique) and linear estimation using b values of 1 and 1,000 only (two-point technique). A high correlation between the two methods was noted (R2 = 0.999), and the mean percentage difference was 0.84%. These results suggest there is little error in estimating brain ADCs using a two-point technique.
authors.affiliation: Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1088, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Burdette
authors.forename: A D
authors.initials: AD
authors.lastname: Elster
authors.forename: P E
authors.initials: PE
authors.lastname: Ricci
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology*; D001932:Brain Neoplasms / Q000175:diagnosis; D002543:Cerebral Hemorrhage / Q000175:diagnosis; D002544:Cerebral Infarction / Q000175:diagnosis; D004058:Diffusion; D005260:Female; D006406:Hematoma / Q000175:diagnosis; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results