Rupture-associated angioarchitectural features and assessment of the Ruptured Arteriovenous Malformation Grading...

Children with cerebral arteriovenous malformation (AVM) have a high risk of spontaneous intracerebral hemorrhage. The identification of patients at risk for AVM rupture and accurate prediction of outcomes are critical to guide management strategies. The authors examined the angioarchitectural features of pediatric AVMs associated with hemorrhagic presentation and reviewed the utility of the Ruptured AVM Grading Scale (RAGS) for outcome prognostication in pediatric patients treated surgically at a single institution.

The authors retrospectively reviewed the records of pediatric (age ≤ 18 years) patients who underwent resection of AVMs at their institution between 1998 and 2023. Demographic factors, clinical presentation, and angioarchitectural details including nidus size, location, venous drainage, presence of flow-related aneurysm, presence of an en passage vessel, and perforator vessel supply were collected. Clinical presentation and angioarchitecture were compared in patients with ruptured and unruptured AVMs. In patients with ruptured AVMs, the area under the receiver operating characteristic curve (AUROC) was calculated based on their RAGS scores at 3 follow-up time points using dichotomous analysis of the modified Rankin Scale score as the response variable.

Of the 62 patients included in this study, 59.7% presented after rupture. Patients with ruptured AVMs had, on average, a smaller nidus (24.84 vs 38.24 mm, p < 0.001) and a higher percentage of deep venous drainage (64.9% vs 32.0%, p = 0.009). Multivariable logistic regression analysis confirmed smaller nidus diameter (OR 0.93, 95% CI 0.87-0.98, p = 0.016) and presence of deep venous drainage (OR 10.78, 95% CI 1.73-42.94, p = 0.011) as independent predictors of hemorrhagic presentation. Good clinical outcomes (modified Rankin Scale [mRS] score ≤ 2) at last follow-up were similar for the unruptured and ruptured cohorts (85.5% vs 88.0%, p = 0.230). For patients with ruptured AVMs, the AUROC values for the RAGS scoring system were 0.48 at 3 months, 0.67 at 1 year, and 0.70 at the last known follow-up.

Smaller AVM nidus size and deep venous drainage were associated with hemorrhagic presentation in children with AVMs. Although the AUROC for RAGS improved with longer follow-up periods, it did not reach the 0.8 threshold needed for clinical utility.