Angioarchitecture of brain AVM determines the presentation with seizures: proposed scoring system

Seizures are a common presentation in patients with brain arteriovenous malformations, but the pathogenesis of seizures remains poorly understood. The purpose of our study was to analyze various morphologic and hemodynamic characteristics of unruptured BAVMs presenting primarily with seizures and, on the basis of these, to propose a scoring system to predict seizures in patients with BAVMs.

In a retrospective review of our BAVM data base from 2000 to 2009, after excluding patients with ruptured BAVMs, we classified patients into 2 groups, those with and without seizures at presentation. Clinical, angiographic, and hemodynamic characteristics on cerebral angiograms of all these patients were studied. The association between various angioarchitectural variables and seizure presentation was examined, and these results were used to guide the development of criteria to predict presentation with seizures.

Of 1299 patients in our data base, we finally analyzed 33 patients with unruptured BAVMs with seizures and 45 patients with unruptured AVMs without seizures. Location, fistulous component in the nidus, venous outflow stenosis, and the presence of a long pial course of the draining vein were identified as the strongest predictors of seizures. The proposed scoring system had good predictability of presentation with seizures.

Specific angioarchitectural characteristics of unruptured BAVMs may predict occurrence of seizures and may help in targeted treatment.