Different responses of cavernous malformations and arteriovenous malformations to radiosurgery.

TitleDifferent responses of cavernous malformations and arteriovenous malformations to radiosurgery.
Publication TypeJournal Article
Year of Publication2009
AuthorsTu J, Stoodley MA, Morgan MK, Storer KP, Smee R
JournalJ Clin Neurosci
Date Published2009 Jul
KeywordsArteriovenous Malformations, Brain Neoplasms, Dose-Response Relationship, Radiation, Hemangioma, Cavernous, Central Nervous System, Humans, Longitudinal Studies, Microscopy, Electron, Transmission, Muscle, Smooth, Vascular, Radiosurgery

The vascular structure of cavernous malformations (CMs) and arteriovenous malformations (AVMs) is different and they have differing clinical responses to radiosurgery. The structural differences of irradiated and non-irradiated CMs and AVMs were examined to clarify their differential responses to radiosurgery. CMs showed a greater ratio of intraluminal diameter to vessel wall thickness and a lack of subendothelial fibroblasts, myofibroblasts and smooth muscle cells compared with AVMs. Partial proteinaceous clots (19-22% of lumen) formed in CM sinusoids after radiosurgery but complete vaso-occlusion did not occur for up to 6 years after radiosurgery. In contrast, complete vaso-occlusion (91-98% of lumen) by fibrin thrombi that are permanent clots was observed in AVM vessels. Radiation-induced neuronal loss, neurofibrillary degeneration of neurons and myelin fragmentation were typical in the surrounding brain tissue of the irradiated lesions. The different structure and cellular composition of CMs and AVMs is likely to influence their responses to radiosurgery.

Alternate JournalJ Clin Neurosci
PubMed ID19342244