Fig. 2.

An example of the texture analysis procedure. a Maximum intensity projection of FDG-PET of a male patient in his 50 s with diffuse large B-cell lymphoma. A huge tumor in the right neck was shown (arrow). b A transaxial slice showing the tumor with SUV window 0 to 6 indicates that the entire tumor metabolizes homogenously; however c the same slice with SUV windows 0 to 15 depicts the intra-tumoral heterogeneity of metabolism. d The tumor was segmented using SUV≧3 as the criteria. e A total of 7206 voxels were extracted from the segmented region. Not only SUV but also the (x,y,z) coordinate are important for the following calculation. f After 64-degree discretization, the GLCM (64 × 64) was calculated. g EntropyGLCM was calculated from the GLCM. The value was 6.60 in this case