FIG 5. FLAIR images from a typical examination. Left to right, Sections after one course, four courses, and seven courses of high-dose IV MTX therapy; at the end of therapy; and at 2 years after the completion of therapy.

A, Transient LE. Although the first image is normal, the second and third show LE, which resolves by the fourth and remains normal on the final image.

B, Persistent LE. First image is normal, but all others, including the 2-year follow-up image, show LE.