Abstract TP143: Early Angiographic Neovascularization Response to EDAS Surgery in Adults with Intracranial Arterial Stenosis

Abstract

Introduction: Significant neovascularization following indirect revascularization procedures, such as encephaloduroarteriosynangiosis (EDAS), has traditionally been considered to develop slowly over time. However, a recent study of angiography following indirect revascularization procedures demonstrated early signs of revascularization as early as 4 days following surgery. While we have previously published demonstration of robust revascularization at 6 months and later following surgery, here we present a subset of patients, all with non-moyamoya intracranial arterial stenosis (IAS), with earlier angiographic evaluation following EDAS. Methods: We retrospectively reviewed charts of adult patients who have undergone EDAS for non-moyamoya IAS. These early angiograms were evaluated for signs of revascularization and graded according to the scale presented by Perren et al (1, no sign of neoangiogenesis; 2, one-to-four new transcortical vessels; 3, > four new transcortical vessels). Results: Ten patients (mean age 43 years, 8 females) were found with follow-up cerebral angiography within 6 months of surgery (1 each at 1, 2 & 3 mo, 2 at 1.5 mo, 3 at 5 mo, and 4 at 6 mo). All angiograms demonstrated neovascularity, regardless of underlying diagnosis, including scores of 3 (extensive neoangiogenesis) in 80% of cases as early as 1.5 months after surgery. Two patients had grade 2 at 1 & 2 months. Clinically, all patients’ ischemic symptomatology has resolved. Six patients have had no symptoms since surgery while 4 patients had transient episodes consistent with ischemia (TIA) that all resolved by 2 weeks post-operatively (3 at 1 week and 1 at 2 weeks). No patient suffered stroke following EDAS. Conclusion: This series adds to the growing evidence that indirect revascularization procedures can lead to significant neovascularity in a shorter time frame than previously expected in adult patients, including those with non-moyamoya IAS. Further study is required to better define the time course of neoangiogenesis and to evaluate angiogenic mechanisms that contribute to the success of this procedure.