Microsurgery Versus Embolization for Spinal Cord Arteriovenous Malformations: A Proposed Grading System

Area of Science:

• Neurosurgery
• Interventional Radiology
• Vascular Neurology

Background:

• Spinal cord arteriovenous malformations (SCAVMs) present diagnostic and therapeutic challenges due to rarity and complex angioarchitecture.
• A novel grading system was developed to stratify SCAVM complexity based on independent risk factors.

Purpose of the Study:

• To compare treatment outcomes between microsurgery and embolization for SCAVMs.
• To evaluate the efficacy of a new grading system in stratifying treatment risks and outcomes.

Main Methods:

• A cohort of 714 patients with SCAVMs was analyzed, with 308 undergoing microsurgery.
• A grading system was developed using factors: anterior sulcal artery supply, metameric manifestations, lesion diameter, and depth.
• Outcomes including complete obliteration rates, clinical deterioration, and prognosis were compared between microsurgery and embolization across different grades.

Main Results:

• Microsurgery demonstrated higher risks than embolization across all SCAVM grades.
• Microsurgery achieved superior complete obliteration rates for grades 0-2, with similar rates for grades 3-4.
• Long-term clinical deterioration was more frequent after embolization for grade 1, comparable for grades 2-4, and similar for grade 0. Microsurgery showed worse prognosis for grades 1-4.

Conclusions:

• Embolization is recommended as the primary treatment for most SCAVMs.
• Microsurgery may be considered for low-grade SCAVMs (grades 0-1) if embolization is insufficient.
• The developed grading system effectively stratifies angioarchitectural complexity and guides treatment decisions for SCAVMs.