Spetzler-Main AVM grading scale. Graded Feature Points Assigned Size of AVM < 3 cm 3-6 cm >6 cm 1 2 3 Eloquence1 of adjacent brain Noneloquent Eloquent 0 1 Venous drainage Superficial Deep 0 1 'Eloquent areas include: visual, language, and sensorimotor coex; the thalamus and hypothalamus; the internal capsule; the brainstem; the cerebellar peduncles; and the deep cerebellar nuclei.