title: Reproducibility of scan prescription in follow-up brain MRI: manual versus automatic determination.
abstract: In follow-up brain magnetic resonance imaging (MRI), precise reproducibility of the scan prescription is important so that over- or underestimating changes in volumes of clinical interest is prevented. (The scan prescription is defined as the location and orientation of the head with respect to the scan planes of the three-dimensional MRI matrix.) In this study, the misregistration between the original and a second scan was calculated in the case of both manual positioning and automatic positioning. These calculations were carried out both for a healthy volunteer scanned repeatedly and, in a retrospective study, for 225 patients who had an original and at least one follow-up scan. The effects of the scan operator being the same for both scans or being different were also examined. A commercially available 1.5 Tesla MRI system and a six-element head-array coil were employed in all of the imaging. The reproducibility of the scan prescription was determined by the registration of the original scan image to the follow-up scan image by use of the Fourier phase correlation method. Our results showed that (1) the reproducibility by automatic positioning was superior to that by manual positioning (p < 0.05), and (2) there was no significant difference in the results between when the operator was the same or different (p > 0.05). We conclude that, in follow-up brain MRI, automatic positioning should be used, because manual positioning decreases the reproducibility of the scan prescription even if the same operator performs the second scan.
authors.affiliation: Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku, Tokyo 116-8567, Japan. yancy123xyz@gmail.com
authors.forename: Shinya
authors.initials: S
authors.lastname: Kojima
authors.forename: Masami
authors.initials: M
authors.lastname: Hirata
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shinohara
authors.forename: Eiko
authors.initials: E
authors.lastname: Ueno
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000033:anatomy & histology*; D001927:Brain Diseases / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D005500:Follow-Up Studies; D064368:Healthy Volunteers; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008432:Mathematical Computing; D008875:Middle Aged; D056888:Patient Positioning; D010363:Pattern Recognition, Automated; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult