Which of the following technique is the best for differentiating recurrence of brain tumour from radiation therapy induced necrosis?: (A) MRI, (B) Contrast enhanced MRI, (C) PET scan, (D) CT scan
Answer is C. C i.e., PET scan MRI or CT scan are often unable to distinguish radiation necrosis from recurrent tumour PET or SPECT scans may demonstrate that glucose metabolism is increased in tumour tissue but decreased in radiation necrosis, used to distinguish recurrence from radiation necrosisQ.