Imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 may contribute to hemorrhage in cerebellar arteriovenous malformations.

The article presents a study which established that an imbalance of matrix metalloproteinase-9 and matrix metalloproteinase tissue inhibitor-1 may be the underlying mechanism of hemorrhage in cerebellar arteriovenous malformations or primary epilepsy. Expression levels of matrix metalloproteinase-2 and -9 and matrix metalloproteinase tissue inhibitor-1 and -2 in patients presented with cerebellar arteriovenous malformations were examined.