Retinal ependymoma: an immunohistologic and ultrastructural study.

Glial tumors of the retina are rare. Most are syndrome associated and include pilocytic astrocytoma in neurofibromatosis type 1 and subependymal giant cell astrocytoma in tuberous sclerosis complex. Acquired, more conventional, diffuse astrocytomas are less frequent. Ependymoma is exquisitely rare. Herein, we report the clinicopathologic features of the second case of retinal ependymoma. The tumor was sporadic in occurrence and unilateral, low grade, and of cellular type. Its chronic course and large size prompted an initial pathologic diagnosis of "massive retinal gliosis." The literature regarding retinal glial neoplasia including ependymoma as well as the so-called massive retinal gliosis is discussed.