Radiological Imaging after Treatment in High-Grade Glial Tumor

High-grade glial tumors are the most common primary brain tumor in adults. The current standard of care for high-grade glial tumors includes surgical resection followed by combination of radiation with temazolomide treatment and adjuvant temozolomide. The Macdonald Criteria are currently the most widely used guideline for assessing response to therapy in patients with high-grade glial tumors. These are based on the size of the contrast-enhancing lesion in MR imaging. Recently, nontumoral changes in enhancement have been found. It is now clear that evaluation of gadolinium enhancement alone is not adequate to characterize tumor regression or progression. MR diffusion, MR perfusion, MR spectroscopy, and PET imaging will be important adjuncts to traditional imaging for tumor assessment. We review MR imaging findings following high-grade tumor treatment.