Utilidad de las Escalas de Gradación en el Tratamiento Quirúrgico de Malformaciones Arteriovenosas Cerebrales

INTRODUCTION: Brain arteriovenous malformations (AVM) are a complex disease responsible for up to 38% of hemorrhages in patients between 15-45 years old, carrying every bleeding episode a 25-50% risk of morbidity and a 10-20% of mortality. The therapeutic decision in a patient with an AVM needs to consider both the risks of the intervention and the risks of the natural evolution of the disease. OBJECTIVE: To assess the effectiveness of different AVM grading scales in predicting surgical risks according to our experience in a case serie. MATERIAL AND METHOD: A literature review of the AVM grading scales was made, through Pubmed including as key words “brain arteriovenous malformations” and “grading scale”. A retrospective analysis was made of patients with AVM who were operated in our institution, they were classified according to the scales and their results were compared. RESULTS: 90 patients were operated in our institution with AVM. Retrospectively, they were classified according to the Spetzler-Martin (SM), Spetzler-Ponce (SP), Lawton supplementary, and the sub-classifications in AVM grade 3, from Lawton and de Oliveira. Good outcome were considered when modified Rankin Scale (mRs) was equal or less than 2. The follow-up ranged from 12-48 months, having good outcome in 100% of AVM SM grade I, 91,7% grade II, 80% in grade III and 42,9% in grade IV. Using the SP scale, 93,7% of good outcome in grade A, 80% in grade B and 42,9% in grade C. In the sub-classification of AVM SM 3, we found 84% of good outcome in type 3A de Oliveira and 71,3% in type 3B. According to the Lawton scale, good outcome were found in 92% in type 3-, 72,1% in type 3+ and 60% in type 3. Using Lawton supplementary scale combined with SM, there were 100% of good outcome in grades II and III, 85,7% in grade IV, 87,6% in grade V, 80% in grade VI, 75% in grade VII, 66,6% in grade VIII. CONCLUSION: In our serie, we reaffirm the effectiveness to predict surgical risk of the following scales: SM, SP and the Lawton’s sub-classification of AVM grade 3. Specially, the use of the supplementary Lawton-Young scale in the surgical treatment of bleeding AVMs.