Purpose: To analyze the magnetic resonance (MR) imaging, clinical, and pathologic features of radiation-induced telangiectasia of the brain.
Materials and methods: The clinical and radiation therapy records were reviewed of 20 patients who developed focal hypointense lesions on T2-weighted MR images obtained after radiation therapy of the central nervous system. Pathologic material was reviewed in six patients.
Results: Eleven patients had solitary lesions, and nine had multiple foci on MR images. Fourteen of the 20 patients were less than 20 years old. The appearance ranged from small hypointense foci to larger regions of acute hemorrhage. Hematomas occurred at the site of a previously identified focus of T2 shortening in five patients. Pathologic findings included ectatic thin-walled vessels surrounded by hemosiderin and gliosis, with minimal evidence of necrosis.
Conclusion: Radiation-induced telangiectasia in the brain results in varying amounts of hemorrhage and, occasionally, parenchymal hematomas, and may appear similar to cryptic vascular malformations on T2-weighted MR images.