The appropriate management of unruptured intracranial arteriovenous malformations (AVMs) remains controversial. In the present study, the authors evaluate the radiographic and clinical outcomes of radiosurgery for a large cohort of patients with unruptured AVMs.
From a prospective database of 1204 cases of AVMs involving patients treated with radiosurgery at their institution, the authors identified 444 patients without evidence of rupture prior to radiosurgery. The patients' mean age was 36.9 years, and 50% were male. The mean AVM nidus volume was 4.2 cm3, 13.5% of the AVMs were in a deep location, and 44.4% were at least Spetzler-Martin Grade III. The median radiosurgical prescription dose was 20 Gy. Univariate and multivariate Cox regression analyses were used to determine risk factors associated with obliteration, postradiosurgery hemorrhage, radiation-induced changes, and postradiosurgery cyst formation. The mean duration of radiological and clinical follow-up was 76 months and 86 months, respectively.
The cumulative AVM obliteration rate was 62%, and the postradiosurgery annual hemorrhage rate was 1.6%. Radiation-induced changes were symptomatic in 13.7% and permanent in 2.0% of patients. The statistically significant independent positive predictors of obliteration were no preradiosurgery embolization (p < 0.001), increased prescription dose (p < 0.001), single draining vein (p < 0.001), radiological presence of radiation-induced changes (p = 0.004), and lower Spetzler-Martin grade (p = 0.016). Increased volume and higher Pittsburgh radiosurgery-based AVM score were predictors of postradiosurgery hemorrhage in the univariate analysis only. Clinical deterioration occurred in 30 patients (6.8%), more commonly in patients with postradiosurgery hemorrhage (p = 0.018).
Radiosurgery afforded a reasonable chance of obliteration of unruptured AVMs with relatively low rates of clinical and radiological complications.
Abbreviations used in this paper:ARUBA = A Randomized Trial of Unruptured Brain Arteriovenous Malformations; AVM = arteriovenous malformation; DSA = digital subtraction angiography; HR = hazard ratio; RIC = radiation-induced change.
Al-ShahiRBhattacharyaJJCurrieDGPapanastassiouVRitchieVRobertsRC: Prospective, population-based detection of intracranial vascular malformations in adults: the Scottish Intracranial Vascular Malformation Study (SIVMS). Stroke34:1163–11692003
FlickingerJCKondziolkaDLunsfordLDKassamAPhuongLKLiscakR: Development of a model to predict permanent symptomatic postradiosurgery injury for arteriovenous malformation patients. Int J Radiat Oncol Biol Phys46:1143–11482000
JessurunGAKamphuisDJvan der ZandeFHNossentJC: Cerebral arteriovenous malformations in The Netherlands Antilles. High prevalence of hereditary hemorrhagic telangiectasia-related single and multiple cerebral arteriovenous malformations. Clin Neurol Neurosurg95:193–1981993
PollockBEKondziolkaDFlickingerJCPatelAKBissonetteDJLunsfordLD: Magnetic resonance imaging: an accurate method to evaluate arteriovenous malformations after stereotactic radiosurgery. J Neurosurg85:1044–10491996
SirinSKondziolkaDNiranjanAFlickingerJCMaitzAHLunsfordLD: Prospective staged volume radiosurgery for large arteriovenous malformations: indications and outcomes in otherwise untreatable patients. Neurosurgery58:17–272006
WedderburnCJvan BeijnumJBhattacharyaJJCounsellCEPapanastassiouVRitchieV: Outcome after interventional or conservative management of unruptured brain arteriovenous malformations: a prospective, population-based cohort study. Lancet Neurol7:223–2302008
WegnerREOysulKPollockBESirinSKondziolkaDNiranjanA: A modified radiosurgery-based arteriovenous malformation grading scale and its correlation with outcomes. Int J Radiat Oncol Biol Phys79:1147–11502011