Dural arteriovenous fistulae (DAVF) Flashcards
DAVF
Is AVM in the dura
Acquire
Supply DAVF
ICA ,ECA, VA
For tentorium DAVF supply ➡️ Arterial feeders are derived from the meningo-hypophyseal trunk, occipital artery, ascending pharyngeal artery, and vertebral artery.
Common 📍 for DAVF
🌟 transverse/sigmoid Left
Tentorium ⛺️/ ethrmiodal 👃
Anteriorfossa/ ethmiodal 👃
Middle fossa/ Sylvian
SSs
CCF cavernous= carotid-cavernous fistula (CCF
Pahtogensis of DAVF theory
1-Venous thrombosis 💢 awake embryonic dural arteriovenous channels
2-venous hypertension/thrombosis promotes local angiogenesis and the de novo formation of DAVF47
- the DAVF may arise first and itself result in venous sinus thrombosis
Population common
Female
In peds 🧸➡️ complex, bilateral dural sinus malformations.
Presentation DAVF
MCC pulstile tinnitus ➡️ high flow fistulas in the transverse sinus/sigmoid location.
Venous HTn ➡️⬆️ ICP , ▶️ poor cerebral venous drainage ▶️ imapre arachnoid granulation ▶️ HC
Carotid - cavernous fistula ➡️ proptosis
Compression of the carotid artery may result in a ⬇️ in bruit intensity.
Common cause of morbidity and mortality in DAVF
Venous HTN and ICP
Indication for DAVF tx
⏏️ ICP
DX of DAVF
CTA
MRA
DSA ⭐️
What differencate high from low grade
Cortical venous drainage ▶️ high grade
Borden classification
Cognard ⭐️⭐️
Applicable
The Cognard classification divides dural arteriovenous fistulas into 5 types according to the following features:
5 Location of fistula 5 Presence of cortical venous drainage 5 Direction of flow 5 Presence of venous ectasia
Retrograde flow to cortical vein are high risk bleeding and IC➖HTn
Outcome
90% of beningn DAVF ( no cortical V drain ) reminds benign
aggressive ( cortical V drain ) high risk of 🩸, neurological deficit and mortality
Common 📍 for aggressiveDAFV
🏕️ tentorium➡️ middle f/ Sylvia’s ➡️ anterior F / ethmiod
Indication for intervention
- presence of cortical venous drainage
- neurologic dysfunction
- hemorrhage
- orbital venous congestion
- refractory symptoms (headache, pulsatile tinnitus)or change sx
Tx DAVF
Manual carotid self-compression ( thrmbosis rare 22% , clinic
A improvement 33% )
Endovascular ➡️ coil through vein ➡️ 1- close shunt
Surgery ▶️ , fatal hemorrhage 🩸
SRS ▶️ best replant 📍 transverse sigmoid , 1650cgy-1900cgy)
Surgical option for DAVF
- radical fistula excision
- sinus skeletonization
- disconnection of cortical venous drainage
- ligation of the fistulous point and/or outflow vein
- sinus packing
- coagulation of arterial feeders to the lesion
Most common site favorable for surgery > Endovascular
anterior fossa/ethmoidal
- tentorial DAVFs
risk factors ⬆️ hemorrhage from DAVF
cortical venous drainage, focal neurological deficits, DAVFs located in the posterior fossa, male sex, and increasing age.
DAVF antiplatelet or anticoagulant agents should avoid
to prevent interference with spontaneous thrombosis of the DAVF.
Transvenous treatment is appropriate
Cognard type IIb fistula
Syndrome with DAVF
Ehlers-Danlos syndrome, fibromuscular dysplasia, or neurofibromatosis type 1.
SSS DAVF supply
MMA
Anterior fossa DAVF presentation
SAh
Foramen magnum DAVFs present with
Mylopathy
Torcular Herophili DAVFs had
aggressive neurological symptoms.
