Spetzler-Martin AVM Grade (+ Lawton-Young)
Spetzler-Martin brain-AVM grade (1986) with the Lawton-Young supplementary score: surgical-risk grade for a cerebral arteriovenous malformation.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Nidus size
- > 6 cm (3)
- Eloquent cortex
- Yes
- Deep venous drainage
- Yes
- Age band (supplementary)
- > 40 years (3)
- Unruptured
- No
- Diffuse nidus
- No
Result: Spetzler-Martin grade V (core sum 5); supplemented Spetzler-Martin–Lawton-Young total 8.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Core I–V
- size (<3 cm 1, 3-6 cm 2, >6 cm 3) + eloquent (1) + deep venous (1). Lower grades carry lower combined surgical morbidity per the source.
- Supplemented
- core + age (<20 1, 20-40 2, >40 3) + unruptured (1) + diffuse (1), total 2-10; refines surgical selection.
What you enter
- Nidus size (<3 cm / 3-6 cm / >6 cm)
- Eloquent cortex
- Deep venous drainage
- Age band (supplementary): <20 / 20-40 / >40
- Unruptured (supplementary)
- Diffuse nidus (supplementary)
How this is calculated
Spetzler RF, Martin NA. A proposed grading system for arteriovenous malformations. J Neurosurg. 1986;65(4):476-483; Lawton MT, et al. A supplementary grading scale for selecting patients with brain AVMs for surgery. Neurosurgery. 2010;66(4):702-713. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.