Slowly Enhancing Lesions after Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformations

We present the contrast-enhanced dynamic MR imaging appearance of cerebral arteriovenous malformations (AVM) following gamma knife radiosurgery and discuss the implications of this finding with respect to treatment. Dynamic MR images obtained in our three AVM patients following radiosurgery revealed slowly enhancing lesions. This pattern is not observed in all cases involving AVMs following gamma knife radiosurgery. When it is present, a haemangioma-like lesion should be considered.