Brain Arteriovenous Malformations Treated with Linear Accelerator-based Stereotactic Radiosurgery: A Latin American Experience

Abstract

Background Stereotactic radiosurgery (SRS) is a reasonable treatment for brain arteriovenous malformations (bAVMs) not suitable for microsurgery. However, limited data exists on linear accelerator (LINAC)-based SRS, a key option in low- and middle-income countries where access to technologies like Gamma Knife or Cyber Knife is restricted. This study aimed to determine the obliteration rate and outcomes of bAVMs treated with LINAC-based SRS guided by triple fusion imaging at a quaternary care institution in Latin America. Methods We conducted a retrospective observational study including patients with bAVMs treated with LINAC-based SRS between 2011 and 2017 at a hospital in Bogota, Colombia. Data was collected from medical records and telephone interviews. The primary outcome was 3-year obliteration rate. Secondary outcomes included intracranial bleeding, headaches, epilepsy, and neurological deficits before and after radiosurgery. Data analysis involved descriptive statistics, central tendency measures, and logistic regression. Results The study included 82 patients, 51.2% were female, with a third residing outside of Bogota. Ruptured bAVMs were present in 44% of patients, 74.4% were located in eloquent brain areas and most were Spetzler Martin grade III. Prior embolization was performed in 57.3% of patients, and the median radiosurgery dose was 20 Gy (SD 1.6). Satisfactory 3-year follow-up was possible in 59 participants with a complete obliteration rate of 57.4%. The most common post-SRS symptom was headache (53.8%), followed by focal neurological deficits (33.3%). Two deaths due to bAVM rupture were reported post-SRS. The radiosurgery dose was significantly associated with bAVM obliteration (OR 1.65, 95% CI 1.05–2.61, p-value = 0.030). Conclusions Linear accelerator-based SRS with triple fusion imaging offers a viable option for managing bAVMs in settings with limited access to cutting-edge technologies. However, there is a compelling need for improving patient follow-up in future research, which will contribute to a more accurate assessment of obliteration rates and other treatment outcomes.