Dural arteriovenous shunt classifications
| Borden (1995) | 1 Direct sinus drainage | 2 Sinus drainage+CVR | 3 CVR only | ||||||
| Cognard (1995) | 1 Antegrade sinus drainage | 2 | 3 CVR only | 4 CVR+venous ectasia | 5 Spinal perimedullary drainage | ||||
| 2a Retrograde sinus drainage | 2b Antegrade sinus drainage+CVR | 2a+b Retrograde sinus drainage+CVR | |||||||
| Zipfel (2009) | 1 Dural sinus drainage | 2 Dural sinus drainage+CVR* | 3 CVR* only | ||||||
| 2+Asympt | 2+Sympt | 3+Asympt | 3+Sympt | ||||||
| Baltsavias (2014) | D-E-S: Borden 3/Cognard 3 or 4, D-E-nS: Borden 3/Cognard 3, D-nE-S: Borden 2/Cognard 2b D-nE-nS: Borden 2/Cognard 2b, nD-E-S: Borden 3/Cognard 4, nD-E-nS: Borden 3/Cognard 2b or 3 nD-nE-S: Borden 2/Cognard 2b or 2a+b, nD-nE-nS: Borden 2/Cognard 2b or 2a+b | ||||||||
| SNIS S&G (2015) | 1 No CVR | 2 CVR | |||||||
| 1a Asympt | 1b Sympt | 2a Asympt | 2b Sympt | ||||||
Asympt, asymptomatic presentation; CVR, cortical venous reflux; CVR*, original description was cortical venous drainage; D-E-S system, D (directness of leptomeningeal venous drainage), E (exclusivity of leptomeningeal venous drainage) and S (venous strain); n (non or no); SNIS S&G: Society of Neurointerventional Surgery Standard and Guideline Committee; Sympt, symptomatic presentation.