Volume-staged versus dose-staged radiosurgery outcomes for large intracranial arteriovenous malformations.
OBJECT
The aim in this paper was to compare the outcomes of dose-staged and volume-staged stereotactic radio-surgery (SRS) in the treatment of large (> 10 cm(3)) arteriovenous malformations (AVMs).


METHODS
A systematic literature review was performed using PubMed. Studies written in the English language with at least 5 patients harboring large (> 10 cm(3)) AVMs treated with dose- or volume-staged SRS that reported post-treatment outcomes data were selected for review. Demographic information, radiosurgical treatment parameters, and post-SRS outcomes and complications were analyzed for each of these studies.


RESULTS
The mean complete obliteration rates for the dose- and volume-staged groups were 22.8% and 47.5%, respectively. Complete obliteration was demonstrated in 30 of 161 (18.6%) and 59 of 120 (49.2%) patients in the dose- and volume-staged groups, respectively. The mean rates of symptomatic radiation-induced changes were 13.5% and 13.6% in dose- and volume-staged groups, respectively. The mean rates of cumulative post-SRS latency period hemorrhage were 12.3% and 17.8% in the dose- and volume-staged groups, respectively. The mean rates of post-SRS mortality were 3.2% and 4.6% in dose- and volume-staged groups, respectively.


CONCLUSIONS
Volume-staged SRS affords higher obliteration rates and similar complication rates compared with dose-staged SRS. Thus, volume-staged SRS may be a superior approach for large AVMs that are not amenable to single-session SRS. Staged radiosurgery should be considered as an efficacious component of multimodality AVM management.