From the archives of the AFIP - Superficial gliomas: Radiologic-pathologiccorrelation

Glial neoplasms that are peripherally located and involve the cortical gray matter are noteworthy because of their predilection to serve as a seizure locus, their amenability to surgical resection, their generally favorable p rognosis, and their characteristic imaging features, which facilitate diagn osis before surgery. The smaller lesions include ganglioglioma and dysembry oplastic neuroepithelial tumor. Gangliogliomas contain both neuronal and gl ial components and occur most commonly in the temporal lobe. Variant forms of gangliogliomas may occur and are related to the different compositions o f the underlying cellular population. Gangliocytomas lack glial cells and a re located both in the cerebral hemispheres and the cerebellum. Lhermitte-D uclos disease represents a specific type of cerebellar gangliocytoma with d ysplastic features and is characterized by a laminar pattern at imaging. Dy sembryoplastic neuroepithelial tumors occur predominantly in children and y oung adults with partial seizures and most commonly arise in the temporal l obe, frequently in combination with cortical dysplasia. Surrounding vasogen ic edema is conspicuously absent in both gangliogliomas and dysembryoplasti c neuroepithelial tumors. The larger masses in this group include desmoplas tic infantile ganglioglioma and pleomorphic xanthoastrocytoma and tend to i nvolve the leptomeninges and cortical territory. Both invoke an intense des moplastic reaction, which appears as an enhancing soft-tissue component at imaging.