The factors associated with obliteration following stereotactic radiosurgery in patients with brain arteriovenous malformations: a meta‐analysis

• Published in: ANZ journal of surgery Vol. 92; no. 5; pp. 970 - 979
• Main Authors: Li, Weiyan, Wang, Yuqiang, Lu, Lantao, Zhang, Yi
• Format: Journal Article
• Language: English
• Published: Melbourne John Wiley & Sons Australia, Ltd 01.05.2022; Blackwell Publishing Ltd
• Subjects: arteriovenous malformations; Brain; Brain surgery; Confidence intervals; Embolization; Estimates; Follow-Up Studies; Gender; Hemorrhage; Humans; Intracranial Arteriovenous Malformations - complications; Intracranial Arteriovenous Malformations - radiotherapy; Meta-analysis; obliteration; Patients; Radiation; Radiation dosage; Radiology; Radiosurgery; Radiosurgery - adverse effects; Regression analysis; Retrospective Studies; Statistical analysis; stereotactic radiosurgery; Surgery; Treatment Outcome; vascular disorders; meta-analysis; arteriovenous malformations; vascular disorders; obliteration; stereotactic radiosurgery
• ISSN: 1445-1433; 1445-2197; 1445-2197
• DOI: 10.1111/ans.17299

Background Various factors have been reported to affect the obliteration of brain arteriovenous malformations (AVM) following stereotactic radiosurgery (SRS). This meta‐analysis was conducted to identify the factors potentially associated with AVM obliteration after SRS. Methods We comprehensively searched databases and included studies that evaluated predictors of AVM obliteration after SRS using Cox proportional hazard regression analysis. Hazard ratios (HRs) with 95% confidence intervals (CIs) were utilized as effect estimates. Results Twelve studies, involving 4415 AVM cases, were included. According to combined estimates on univariate (UV) and multivariate (MV) analysis, age, gender and prior haemorrhage did not affect the closure probability. The following factors showed a significant and independent association with increased AVM obliteration: smaller AVMs maximal diameter (MV, HR: 1.32), smaller AVM volume (MV, HR: 1.05), AVM volume <10–15 cc (MV, HR: 1.55), higher margin dose (MV, HR: 1.05), margin dose ≥17–18 Gy (MV, HR: 3.71) and early treatment period (MV, HR: 1.78). Previous embolization and deep‐seated AVM were independently negative predictors of obliteration whereas deep venous drainage was a positive predictor. Prior surgery, compactness of nidus, lower grading scores and higher SRS maximum dose were associated factors subject to confounding factors. Conclusion Multiple factors associated with obliteration should be taken into consideration for selection of candidates with AVMs for SRS. AVM volume and radiation dose are the most prominent factor in assessing obliteration after SRS. Age, gender and prior haemorrhage may not affect the consideration of SRS treatment. Cautious use of SRS is needed for previously embolized AVM patients. The present analysis collected findings across studies that analyzed possible variables related to obliteration of AVM after treatment of stereotactic radiosurgery using univariate and/or multivariate analysis under Cox proportional models.