Unusual Case of Radiation-Induced Cavernous Malformation after Gamma Knife Radiosurgery for Meningioma

Jang, Chang Ki; Kim, Minsoo; Jung, Na Young; Kim, Young Goo; Chang, Won Seok; Jung, Hyun Ho; Chang, Jin Woo; Park, Yong Gou

Case report

Journal of the Korean Society of Stereotactic and Functional Neurosurgery 2015;11(2):120-123.
Published online September 30, 2015.

Unusual Case of Radiation-Induced Cavernous Malformation after Gamma Knife Radiosurgery for Meningioma

Chang Ki Jang, Minsoo Kim, Na Young Jung, Young Goo Kim, Won Seok Chang, Hyun Ho Jung, Jin Woo Chang, Yong Gou Park

Department of Neurosurgery, Yonsei Gamma Knife Center, Yonsei University College of Medicine, Seoul, Korea

Abstract

We report an unusual case of delayed bleeding, highly suspected to be a radiation-induced cavernous malformation after gamma knife radiosurgery for meningioma. A 59-year-old woman underwent gamma knife radiosurgery with a marginal dose of 15 Gy with the 50% isodose line for parasagittal meningioma. After 5 years, magnetic resonance imaging (MRI) showed a marked decrease in the volume of the meningioma. The patient gradually developed right side weakness 7 years after the gamma knife radiosurgery. We performed another MRI scan and it showed a new hemorrhage compatible with cavernous malformation at the site of irradiation. Her weakness was conservatively treated and improved after about a month.

Key Words: Radiation-induced cavernous malformation, Gamma knife radiosurgery, Meningioma, MRI.