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Spetzler-Martin Score

Spetzler-Martin score is used for the evaluation of surgical risk in patient suffering for AVMs. 


Graded Feature
Size of AVM Small (<3 cm) 1
  Medium (3 cm - 6 cm) 2
  Large (>6 cm) 3
Eloquence of adjacent brain Non-eloquent 0
  Eloquent 1
Pattern of venous drainage Superficial 0
  Deep 1


% No Deficits
% Minor Deficits
% Major Deficits
1 100 0 0
2 95 5 0
3 84 12 4
4 73 20 7
5 69 19 12

Spetzler-Ponce Classification

Spetzler-Ponce classification concerns treatment and prognosis of AVMs and it is based on the Spetzler-Martin score.


Spetzler-Martin Grade
A 1-2 Resection
B 3 Multimodal
C 4-5 No Treatment


Note that in class C the treatment is admitted in presence of:

    • Recurrent hemorrhage
    • Progressive neurological deficits
    • Steal-related symptoms
    • AVM-related aneurysms


Yasargil's Classification

Yasargil classification is used for the evaluation of Vein of Galen malformations (VOGMS).



Pure cisternal fistula between pericallosal arteries, PCA and the vein of Galen

2 Fistoulous connections between the thalamoperforators (basilar and P1) and the vein of Galen
3 Mixed form (type 1 and type 2 features)

Plexiform with one or more intrinsic niduses within the mesencephalon or thalamus with draining veins emptying into the vein of Galen:

a. Pure Plexiform

b. Plexiform combined with Type 1 (fistoulous cisterna nidus)

Cognard Classification

Cognard classification assess venous drainage patterns of dural arterovenous fistulas and prognosis through angiographic methods.


1 Anterograde drainage into sinus arteries, PCA and the vein of Galen

a. Drainage into main sinus with reflux into a secondary sinus

b. Drainage into main sinus with reflux into cortical veins

c. Mixed type (2a and 2b)

3 Direct cortical venous drainage without ectasia
4 Direct cortical venous drainage with ectasia (>5 mm or 3x larger than diameter of draining vein)
5 Drainage into the spinal perimedullary veins



A proposed grading system for arteriovenous malformations. Robert F.Spetzler, M.D Journal of Neurosurg 65:476-483, 1986

A 3-tier classi cation of cerebral arteriovenous malformations. RobeRt F. Spetzler, M.D., and FRanciSco a. ponce, M.D. Journal of Neurosurg 114:842–849, 2011

The prospective application of a grading system for arteriovenous malformations. Hamilton MG, Spetzler RF. Neurosurgery 34: 2-7, 1994

How safe is arteriovenous malformation surgery? A prospective, observational study for surgery as first line treatment for bran arteriovenous maformations. Davidson AS, Morgan MK. Neurosurgery 66: 498-505, 2010






Federico Nicolosi, MD

University of Milan
"Spedali Civili" Hospital Brescia (Italy)
Scientific Team - UpSurgeOn

Giorgio Saraceno, MS

Medical Student
University of Brescia (Italy) 
Scientific Team UpSurgeOn