Decreased calcification of a petroclival meningioma after gamma knife radiosurgery.

Stereotactic radiosurgery (SRS) has been well reported in the treatment of certain calcified intracranial lesions such as meningiomas. However, reduction in the calcified portion of the tumour after SRS treatment has not been reported. We present the case of a 76-year-old man with a right petroclival lesion consistent on imaging with a calcified meningioma. The lesion progressed on serial neuroimaging studies, and the patient elected to undergo Gamma Knife radiosurgery. No complications were encountered during the radiosurgery. The patient underwent follow-up imaging at 4 and 8 months, during which the lesion was seen to remain stable in overall size, but with marked decrease in the calcified component. Stereotactic radiosurgery can lead to the reduction of all aspects of meninigomas including the calcified component. The radiobiological effects of high dose ionising radiation may result in bony changes and, thereby, decrease intratumoural calcification of an intracranial tumour. 2014 BMJ Publishing Group Ltd.