Stereotactic radiosurgery has durable outcomes in arteriovenous malformations

A new study published in Stroke Journal suggests that in arteriovenous malformations (AVM) patients treated with stereotactic radiosurgery (SRS) there is an annual risk of less than 1% for intracranial bleeding and recurrent arteriovenous shunting.

Although total nidal complete annihilation of brain arteriovenous malformations is commonly thought to constitute a long-term treatment, post-obliteration bleeding and AVM recurrence are becoming more common. As a result, Ching-Jen Chen and colleagues conducted this research to determine the risks of hemorrhage and nidal recurrence in obliterated AVMs treated with stereotactic radiosurgery.

The International Radiosurgery Research Foundation conducted a retrospective cohort study of AVM patients treated between 1987 and 2020. AVM obliteration on digital subtraction angiography (DSA) was included in the study. Hemorrhage and AVM recurrence were the two outcomes. The duration of follow-up started when the AVM was obliterated and ended when there was a further hemorrhage, AVM recurrence, additional AVM therapy, or loss to follow-up. Risk and survival assessments were done on an annualized basis. For post-obliteration hemorrhage, a sensitivity study of patients with AVM obliteration on magnetic resonance imaging or DSA was also done.

The key findings of this study were as follow:

1. A total of 1632 SRS-treated patients with AVM obliteration on DSA were included in the study.

2. Pediatric patients made up 15% of the group, and 42% of the AVMs had previously burst.

3. After AVM obliteration, the average imaging follow-up was 22 months.

4. Over 2223 patient-years of follow-up (0.72 percent /y), 16 hemorrhages (1.0 percent) occurred among 1607 patients with DSA-confirmed AVM obliteration.

5. Over the 2071 patient-years of follow-up (0.24 percent /y), 5 AVM recurrences (0.32 percent) occurred among the 1543 patients with DSA-confirmed AVM obliteration.

6. AVM recurrence was found in two of the 16 patients who had post-obliteration bleeding (12.5 percent ).

7. In the sensitivity analysis, 16 hemorrhages (0.83 percent) occurred over 2560 patient-years of follow-up (0.63 percent /y) in 1939 patients with post-SRS AVM obliteration on MRI or DSA.

In conclusion, while routine post-obliteration digital subtraction angiography (DSA) is not suggested for SRS-treated AVM patients, long-term neuroimaging may well be beneficial.

Reference:

Chen, C.-J., Ding, D., Kumar, J. S., Kearns, K. N., Ironside, N., Yang, H.-C., Ogino, A., Kano, H., Liscak, R., May, J., Williams, B. J., Gigliotti, M. J., Cockroft, K., McInerney, J., Simon, S., Lee, C.-C., & Sheehan, J. P. (2022). Hemorrhage and Recurrence of Obliterated Brain Arteriovenous Malformations Treated With Stereotactic Radiosurgery. In Stroke. Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1161/strokeaha.122.039213