"Type I leaks (above, below, or between graft components) are generally treated as soon as they are detected. Extension cuffs or covered stents can be inserted at the leaking graft end to improve the seal, or the leak site can be embolised with glue or coils. Rarely, if detected intraoperatively during EVAR, conversion to an open procedure may be required if endovascular sealing of the leak is unsuccessful."
"Endoleak may become evident intra-operatively, years down the track, or anywhere in between. Therefore, lifelong imaging surveillance is necessary. This is usually performed with CT angiography."
"Type I"
"Type II"
"Type IV"
"Type V"
"Type II endoleaks are the most common after abdominal aortic repair, accounting for 80% of cases 5. Retrograde flow through branch vessels continues to fill the aneurysm sac. The most common culprit vessels are lumbar arteries, inferior mesenteric artery or internal iliac artery. This type of leak has been reported in up to 25% of cases. It usually resolves spontaneously over time and requires no treatment. Embolisation of the branch vessel is indicated if the aneurysm sac continues to expand in size."
"Contrast may be seen as a focal region of increased density or a more generalised increase in sac density, in cases where most of the sac has not thrombosed. This may require placing an ROI to measure density."
Expected headings
"Classification"
"Type I"
"Type II"
"Type III"
"Type IV"
"Type V"
"Endoleaks are often asymptomatic as flow within the aneurysm sac is at systemic or near-systemic pressure; if untreated, the aneurysm may expand and is at risk of rupture. As such, aneurysm expansion following EVAR always warrants investigation for endoleak."
"Type II leaks (retrograde flow through a branch) usually spontaneously thrombose. As such, at many institutions, these leaks are not treated immediately; watchful waiting is employed, and if the leak persists, it is treated by embolising the branch vessel with glue or coils. Pre-emptive embolisation of potential sources of collateral flow is sometimes performed prior to stent-graft insertion, particularly the internal iliac artery in select cases. Pre-emptive embolisation of other branch vessels is controversial."
"There are several causes of endoleak, which can be classified into five types as follows:"
"Type III endoleaks are caused by mechanical failure of the stent-graft. There may be a fracture of the stent-graft, hole or defect on the graft fabric, or junctional separation of the modular components. Causes may include defective device material, extreme segment angulation predisposing to fracture, or improper overlap of modular components during insertion."