Yasargil classification

Vein of Galen malformations

Type 1

Pure cisternal fistula between pericallosal arteries, posterior cerebral artery and the vein of Galen.

Type 2

Fistulous connection between the thalamoperforators and the vein of Galen.

Type 3

Mixed form with characteristics of both Type 1 and Type 2 lesions.

Type 4

Plexiform AVM with one or more intrinsic niduses within the mesencephalon or thalamus with draining veins emptying into the vein of Galen.
  • Type 4a: Pure plexiform nidus in the parenchyma of mesencephalon or thalamus.
  • Type 4b: Nidus within the parenchyma combined with fistulous cisternal nidus (Type 1)

    • Reference

    Gupta and Varma. Vein of Galen malformations: review. Neurol India (2004) vol. 52 (1) pp. 43-53