Study selection

We selected articles reporting clinical outcomes for patients with CC-AVMs treated with any of the three treatment modalities (i.e., microsurgery, endovascular embolization, and RS). We included articles that documented patient age, clinical presentation, location of AVM, treatment rendered, and outcomes (modified Rankin Scale [mRS] or posttreatment complications). We included studies not published in English if they met the above selection criteria. We excluded articles that did not report the location of AVM, treatment modality, or outcomes as well as abstracts and letters to the editor that were not published as full reports. Disagreements between the two reviewers about the relevance of a particular study were resolved by discussion and consensus with a third reviewer (Ghaus M. Malik or Maximillian Kole).