Combined treatment approach to cerebral arteriovenous malformation in pediatric patients: stereotactic radiosurgery to partially Onyx-embolized AVM

• Published in: Child's nervous system 2018-11, Vol.34 (11), p.2269-2274
• Main Authors: Umansky, Daniel, Corn, Benjamin W., Strauss, Ido, Shtraus, Natan, Constantini, Shlomi, Frolov, Vladimir, Maimon, Shimon, Kanner, Andrew A.
• Format: Article
• Language: English
• Subjects: Medicine; Medicine & Public Health; Neurosciences; Neurosurgery; Original Paper
• ISSN: 0256-7040; 1433-0350
• DOI: 10.1007/s00381-018-3854-2

Purpose Treatment of cerebral arteriovenous malformations (AVM)—the most common cause of stroke in the pediatric population—can be challenging due to the complexity of size, morphology, and location. There is a significant risk in comparison to AVM treatment among adults. Thus, AVM treatment in the pediatric population imposes unique challenges. Recent improvements include optimized catheter techniques and better embolization materials, such as Onyx, a non-adhesive liquid embolic agent used in the adult population. These improvements have increased the success rate of total and near-total obliteration of cerebral AVM. However, the use of Onyx causes significant distortion of the MR and CT images, which must be accounted for in any radiation treatment planning predicated on CT and MRI. These image distortions impact on the actual delivered dose to the nidus and behoove heterogeneity correction. Our group has previously shared a solution for heterogeneity correction in the adult population. The purpose of this study is to show our experience in this unique group of pediatric patients. Methods This is a retrospective review of pediatric patients, who were undergoing combined endovascular embolization followed by SRS. The cohort consists of 14 patients undergoing SRS treatment in our institute between November 2006 and December 2012 with a mean follow-up of 49.9 months. Within this cohort, we retrospectively reviewed 12 consecutive pediatric patients who underwent a combined endovascular and SRS approach with a mean follow-up of 52.1 months and two patients receiving SRS-only treatment were excluded. Results In our cohort of 14 patients, 7 (50%) were male, with a mean age of 17.3 years (12.0–22.9) at the time of radiosurgery treatment. Mean age of beginning the combined modality treatment was 15.3 years (8.4–20). The median time from diagnosis to SRS was 24.3 months (11.1–64.4 months) in the complete cohort and 25.6 months (11.1–64.4) in the multimodality group. The overall median follow-up period was 49.9 months (range 12.8–118.8 months) in the complete cohort and 52.1 months (range 12.8–118.8 months) in the multimodality group. Eleven (78.6%) patients had at least one episode of hemorrhage prior to treatment. Spezler-Martin grades at baseline ranged from 2 to 5 (mean 3.2). Fifty percent had grade IV and V. Patients underwent a median of 2 (range 1–5) embolization procedures. The radiosurgical treatment dose to the margin of the angiography-based nidus: media