Figure 4.

Images of a patient with a high-grade glioma status post surgery, chemotherapy, and radiotherapy with a clinical suspicion of recurrent tumor on MRI imaging. (A) Contrast-enhanced T1-weighted MRI, (B) summed FDG image, (C) summed [¹¹C]thymidine image, (D) thymidine flux image obtained using compartmental model and mixture analysis. The thymidine flux image, which corrects for labeled metabolites and unincorporated tracer, most clearly delineates the tumor. The patient's subsequent clinical course was consistent with recurrent tumor.