AUTHOR=Chen Xuan , Wang Yiheng , Yu Jinlu 

TITLE=Intra- and post-operative acute hemorrhagic complications of Onyx embolization of brain arteriovenous malformations: A single-center experience

JOURNAL=Frontiers in Neurology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.974954

DOI=10.3389/fneur.2022.974954

ISSN=1664-2295

ABSTRACT=Background: The intra- and postoperative acute (within 72 hours) hemorrhagic complications of endovascular treatment (EVT) for a brain arteriovenous malformation (BAVM) are disastrous. Thus, further experiential summaries are required to fully understand them.
Materials and methods: This was a retrospective study of 25 consecutive BAVM patients who were treated via EVT with Onyx embolization and suffered intra- and postoperative acute hemorrhage. The clinical and imaging data of the patients were recorded, analyzed, and discussed.
Result: The 25 patients were aged 11 to 70 years (mean, 37.2 ±16.1 years), of whom 12 were female (48%, 12/25). Of the 25 hemorrhagic complications, 17 (68%, 17/25) were intraoperative, and 8 (32%, 8/25) were postoperative and occurred between 1 and 12 hours after EVT. Of 17 intraoperative hemorrhages, 13 (76.5%, 13/17) were due to high-pressure Onyx casting. Of 8 postoperative hemorrhages, 6 (75%, 6/8) were attributed to normal perfusion pressure breakthrough. The degree of nidus Onyx embolization was more than 2/3 or complete in 7 (87.5%, 7/8) BAVMs. Draining vein occlusion was observed in 8 (32%, 8/25) of 25 BAVMs. After hemorrhage, conservative treatment was administered in 12 (48%, 12/25) cases, and surgical management was performed in other cases. There were 8 cases of mortality; the remaining 17 patients had follow-up data. Among them, 15 patients had good outcomes, with Glasgow Outcome Scale scores of 5 and 4, accounting for 60% (15/25).
Conclusion: In EVT for BAVMs, intra- and postoperative acute hemorrhagic complications are disastrous; only 60% of patients have a good outcome. Therefore, high-pressure Onyx casting or casting too much Onyx at one time to pursue a high degree of nidus embolization should be performed cautiously, and primary draining vein occlusion should be avoided. In short, EVT needs to be performed carefully.