This question is rather technical and my apologies to regular users of FSL. We would like to use the matrix generated by flirt in another program but need to know the image coordinate system i.e. how the x, y, and z directions are defined. For example, the DICOM image coordinate system has x increasing from right to left, y increasing from anterior to posterior, and z increasing from inferior to superior. Could you please describe the system you use. Thanks, Neva Cherniavsky --------------------------------- Neva Cherniavsky Center for Information Technology Building 12A, Room 2021 National Institutes of Health Bethesda, MD 20892 Phone: 301-402-7655 Fax: 301-402-2867 Email: [log in to unmask] ---------------------------------