Fig 2.

Benefit of creating a dT1 map. Shown are the pre- (A) and postcontrast (B) T1-weighted images from a patient with recurrent glioblastoma treated with bevacizumab and enrolled in the ACRIN 6677 trial. The bright signal on the precontrast image and the subtle enhancement on the postcontrast image make it difficult to determine the extent of enhancing tumor. Alternatively, the dT1 map created from the difference between calibrated pre- and calibrated postcontrast T1-weighted images clearly delineates enhancing tumor as displayed with either color (C) or in gray-scale (D).