Arteriovenous malformations of the brain are congenital anomalies of the blood vessels that are derived from maldevelopment of the capillary network, allowing direct connections between cerebral arteries and veins. The most common presenting symptoms are cerebral hemorrhage and seizures. Focal neurologic deficits and headaches may develop independent of cerebral bleeding. As a result of the widespread use of brain imaging, arteriovenous malformations are increasingly being discovered incidentally.
Specific anatomical features of arteriovenous malformations form the basis of several commonly used grading scales that have been validated as predictive of the treatment outcome. The most widely used scale for this purpose, the Spetzler–Martin grading scale.
Spetzler–Martin Grading Scale for Arteriovenous Malformations of the Brain
| Lesion Characteristic | Points |
| Size | |
| Small (<3 cm) | 1 |
| Medium (3–6 cm) | 2 |
| Large (>6 cm) | 3 |
| Location | |
| Noneloquent | 0 |
| Eloquent | 1 |
| Veins | |
| Superficial | 0 |
| Deep | 1 |
The scale is used to make decisions about treatment risks while taking into account the anatomical characteristics of a cerebral arteriovenous malformation. The grade is the sum of points assigned to the size of the lesion, the location (in or not in the eloquent cortex), and the presence or absence of deep venous drainage. Lower grades (lower total points) indicate lower risk of treatment.
References:
- Solomon RA, Connolly ES Jr. Arteriovenous Malformations of the Brain. N Engl J Med. 2017 May 11;376(19):1859-1866. [Medline]
- Pollock BE, Storlie CB, Link MJ, Stafford SL, Garces YI, Foote RL. Comparative analysis of arteriovenous malformation grading scales in predicting outcomes after stereotactic radiosurgery. J Neurosurg. 2017 Mar;126(3):852-858. [Medline]
Created Sep 20, 2017.
