Fig. 8

a, b & c depict treatment planning in a patient with recurrent anaplastic astrocytoma incorporating DWI sequences. Figure a shows an axial T1 postcontrast slice demonstrating punctate enhancement. Head size measurements were performed in a standard manner on T1 sequences (not shown). Figure b shows the axial DWI sequence with a clear area of hyperintense signal in the region of active disease which was used to obtain axial tumor location measurements. A reference frame is approximated around the head at the level of the scalp. Tumor location coordinates are measured from the right frame to the edges of the DWI signal abnormality thought to represent active tumor at the discretion of the treating physician. Figure 8c shows the coronal T1 postcontrast slice used to map tumor coordinates in the coronal plane. Treatment was planned measuring from a reference frame drawn at the level of the scalp extending to the lowest margin of visible tentorium. Tumor location coordinates are measured from the right frame to the edges of faint enhancement and gyral thickening