Automatic scan prescription for brain MRI

Diagnostic brain MRI scans are usually performed by trained medical technol ogists who manually prescribe the position and orientation of a scanning vo lume, In this study, a fully automatic computer algorithm is described whic h compensates for variable patient positioning and acquires brain MRI scans in a predefined reference orientation. The method involves acquiring a rap id water-only pilot scan, segmenting the brain surface, and matching it to a reference surface. The inverse matching transformation is then used to ad apt a geometric description of the desired scanning volume, defined relativ e to the reference surface, to the current patient. Both pilot scan and pro cessing are performed within 30 sec. The method was tested in 25 subjects, and consistently recovered orientation differences between the reference an d each subject to within +/-5 degrees. Compared to manual prescription, aut omatic scan prescription promises many potential benefits, including reduce d scan times, reproducible scan orientations along anatomically preferable orientations, and better reproducibility for longitudinal studies. (C) 2001 Wiley-Liss, Inc.