title: In vivo evaluation of the reproducibility of T1 and T2 measured in the brain of patients with multiple sclerosis.
abstract: The precision (reproducibility) of relaxation times derived from magnetic resonance images of patients with multiple sclerosis (MS) were investigated. Measurements of 10 MS patients were performed at 1.5 T on two occasions within 1 wk. T1 and T2 was measured using a partial saturation inversion recovery sequence (6 points) and a Carr-Purcell-Meiboom-Gill phase alternating-phase shift multiple spin-echo sequence with 32 echoes. Regions of interest (ROI) were placed both in apparently normal white matter and plaques. The precision (+/- 1.96 SD) and the confidence intervals for T1 and T2 for white matter and plaques were calculated. The precision of T1 for white matter and plaques was respectively +/- 94 msec and +/- 208 msec. The precision of T2 for white matter and plaques was respectively +/- 18 msec and +/- 26 msec. For all measurements the coefficient of variation was about 9%. Judging from our own study and others as well, a precision better than 10% for T1 and T2 would seem unrealistic at present.
authors.affiliation: Danish Research Center of Magnetic Resonance Hvidovre, University Hospital, Copenhagen.
authors.forename: H B
authors.initials: HB
authors.lastname: Larsson
authors.forename: P
authors.initials: P
authors.lastname: Christiansen
authors.forename: I
authors.initials: I
authors.lastname: Zeeberg
authors.forename: O
authors.initials: O
authors.lastname: Henriksen
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis*; D015203:Reproducibility of Results