Vascular malformations

 

1)     AVM

Spetzler-Martin AVM Grading Scale		Points
Size (cm)	0-3	1
	3-6	2
	>6	3
Location	Non-eloquent	0
	Eloquent	1
Deep venous drainage	(-)	0
	(+)	1
AVM total score		1-5

l  The lower the score, the better the outcome

l  Eloquent locations : areas of sensorimotor, language, visual, thalamus, hypothalamus, internal capsule, brain stem, cerebellar peduncles, and deep cerebellar nuclei

l  Size:  largest diameter of nidus on non-magnified angiogram

l  Considered superficial if all drainage is through cortical venous system / Considered deep if any or all is through deep vein (internal cerebral vein, basal veins, precentral cerebellar vein)

 

2)     AVF (Arteriovenous fistula)

 

Classification of dural AVF

By venous drainage pattern

: Cortical venous reflux 존재 여부가 hemorrhage risk & nonhemorrhagic neurologic deficit risk.

 

 

Borden classification

site of venous drainage

presence or absence of CVD(cortical venous drainage)

 

• Borden type I

- direct communication of meningeal arteries with a meningeal vein or dural venous sinus + normal antegrade flow

 

• Borden Type II

- meningeal arteries with a meningeal vein or dural venous sinus  + retrograde flow(to subarachnoid veins -> venous hypertension)

 

• Borden Type III

-meningeal arteries with a subarachnoid vein or isolated sinus segment

-Subclassify: single-hole (a) multiple-hole (b)

 

Borden classification
Type I		Anterograde drainage into dural sinus/meningeal vein
Type II		Anterograde drainage into dural sinus + retrograde cortical venous drainage
Type III		Isolated retrograde cortical venous drainage
Cognard classification
Type I		Anterograde drainage into the main sinus
Type II	a	Drainage into the main sinus with reflux into other sinus(es)
	b	Drainage into the main sinus with reflux into cortical veins
	a+b	Drainage into the main sinus with reflux into other sinuses + cortical veins
Type III		Direct cortical venous drainage without venous ectasia
Type IV		Direct cortical venous drainage with venous ectasia (>5mm and 3 times larger than the diameter of the draining vein)
Type V		Drainage into spinal perimedullary veins

 

Cognard classification

dural sinus drainage 방향

presence or absence of CVD(cortical venous drainage)

venous outflow architecture

• Type I : dural venous sinus + no CVD
• Type IIa : retrogradely to dural venous sinus + no CVD
• Type IIb : antegradely to dural venous sinus + CVD
• Type IIa+b : retrogradely to dural venous sinus + CVD
• Type III : CVD + cortical venous  drainage (no dural venous drainage )
• Type  IV : CVD + cortical venous  drainage + Ectasia
• Type V : CVD + cortical venous  drainage with spinal perimedullary drainage