The Forefront of Gamma Knife Radiosurgery for Brain Arteriovenous Malformations: Our History of Treatment Optimisation Over 30 Years and the Modern Outcomes.

Abstract

Background: Brain arteriovenous malformations (AVMs) can cause cerebral haemorrhage, associated morbidity, and mortality if left untreated. Therefore, prophylactic interventions are essential to manage these lesions. The purpose of this study was to describe our experience of incorporating new technologies into gamma knife radiosurgery (GKRS) for AVMs, aiming to improve its effectiveness and safety.

Methods: We conducted a retrospective observational study that included 1032 patients with AVMs who underwent GKRS at our institution from 1990 to 2022. We reviewed the detailed treatment techniques and updates on GKRS, including tractography-guided identification of critical white matter fibres for eloquent AVMs, GKRS with minimal targeting embolisation for high-haemorrhage risk AVMs, and rotational angiography based GKRS for all AVMs. We evaluated the GKRS outcomes for AVM obliteration, post-GKRS haemorrhage, survival, post-GKRS signal changes, and neurological preservation.

Results: We collected data from 90 patients by using the most advanced techniques. The cumulative obliteration rates were 61.0% at 3 years and 81.6% at 4 years, and the cumulative post-GKRS haemorrhage rates were 2.2% at 2 years and 3.6% at 5 years. Post-GKRS haemorrhage resulted in mortality in one patient (1.1%). Post-GKRS signal change was observed in 31 patients (34%), but only one (1.0%) developed a neurological deficit. Therefore, the cumulative neurological preservation rate was 97.8% at 5 years.

Conclusions: GKRS is a safe and effective treatment for AVMs. The continuous development and use of advanced techniques can lead to favourable outcomes for AVMs. However, further studies with larger samples and longer follow-ups, as well as an analysis of late adverse events, are necessary to better understand the efficacy and safety of GKRS for AVMs.