5/9/2009 Case 2 - answer

The CT - demonstrates contrast adjacent to the iliac limb in the aneurysm sac (it changed on the delayed scan so is not a calcification).

The angiogram - demonstrates the endograft in the aorta and selective catheterization of the artery that supplies a lumbar artery that is causing an endoleak to the sac around the graft.

The answer is type II endoleak in association with an abdominal aortic endograft repair of an abdominal aortic aneurysm.

• Endoleaks are leakage of blood into the excluded aneurysm sac after endograft treatment for an aneurysm (usually AAA)
• Endoleaks are classified and the type has prognostic factors and can indicate the severity of need for treatment.
• Type I - defect in apposition of an end of the stent-graft (proximal or distal) that leads to leakage into the sac.
• - can be seen immediately after deployment due to steep angulation, incomplete expansion, or tortuosity.
• - can be seen late due to changes from shrinking of the sac
• - high pressure situation and needs to be treated urgently.
• - contrast seen centrally with extension to the affected edge of the graft; us - may show pulsation at the edge.
• Type II - most common - a branch is supplying retrograde flow into the aneurysmal sac
• - low pressure situation and may not need repair if the sac is decreasing in size
• - imaging - peripheral contrast within sac
• - if increasing in size - should treat with embolizing of branch
• - often in abdominal aorta - lumbar or IMA is source.
• - many close spontaneously
• Type III - break in body of stent graft or defect in components
• - high pressure situation requiring urgent care
• - a jet may be visible - contrast seen around graft
• - often large amount of contrast seen.
• Type IV - opacification of sac seen at time of procedure and no obvious source identified and stop on their own
• Type V - "endotension" - increasing size of sac (over studies) without sign of source - not emergent but needs treatment.

reference: http://www.ajronline.org/cgi/content/full/192/4/W178