Reproducibility of scan prescription in follow-up brain MRI: manual versus automatic determination

• Published in: Radiological physics and technology 2013-07, Vol.6 (2), p.375-384
• Main Authors: Kojima, Shinya, Hirata, Masami, Shinohara, Hiroyuki, Ueno, Eiko
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Brain - anatomy & histology; Brain Diseases - pathology; Case-Control Studies; Child; Follow-Up Studies; Healthy Volunteers; Humans; Image Enhancement; Image Processing, Computer-Assisted; Imaging; Magnetic Resonance Imaging; Male; Mathematical Computing; Medical and Radiation Physics; Medicine; Medicine & Public Health; Middle Aged; Nuclear Medicine; Patient Positioning; Pattern Recognition, Automated; Radiology; Radiotherapy; Reproducibility of Results; Retrospective Studies; Young Adult
• ISSN: 1865-0333; 1865-0341
• DOI: 10.1007/s12194-013-0211-8

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). 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.