الفهرس 
AnatomyOnly 14 pages are availabe for public view
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Abstract
Popliteal artery aneurysm (PAA) is defined as having a minimal vessel diameter of 1.2 cm and is at least 1.5 times the diameter of the proximal arterial segment. PAAs can be classified according to location in relation to the knee joint (eg, above, behind, below) (Pittathankal AA et al., 2004).
Popliteal aneurysms (PAAs) are the most common peripheral aneurysms and occur almost exclusively in men. Males outnumber females by 20:1. The majority of these aneurysms are degenerative in nature. They are seen more commonly in older men with established cardiovascular disease and are associated with contralateral PA in 64.1% and abdominal aneurysm in 41% (Aulivola B et al., 2004).
Analysis of recent studies has suggested that 25% to 80% of PAs are asymptomatic at the time of operation (Galland RB et al., 2005).
Symptoms include intermittent claudication, rest pain, thrombosis, distal embolization, and, rarely, rupture and pressure symptoms in cases of large aneurysms compressing the medial popliteal, distal sciatic, and common peroneal nerves which presenting as foot drop, which is seen in less than 5% of cases. Popliteal vein compression presents as or mimics D.V.T., rare case of vein rupture has also been reported (Rossi FH et al., 2004).
Acute limb ischemia is present in approximately one third of patients whose PA requires repair (Galland RB et al., 2005).
Surgical treatment is indicated for all symptomatic or complicated PAAs; surgical management is the treatment of choice for asymptomatic PAAs for preventing the ischemic complications from aneurysm embolism or thrombosis and have achieved good surgical results in terms of graft patency and limb salvage rate. The goals of surgical treatment of PAAs are isolation of the aneurysm, preventing distal embolization, and effective revascularization.
Five-year patency rates after surgical repair are _90% for asymptomatic aneurysms and _75% in patients with symptoms. (Aulivola B et al., 2004).
Treatment of popliteal aneurysms with proximal and distal ligation and intervening bypass produces excellent long-term patency and exclusion of the popliteal aneurysm (Box B et al., 2007).
Management of popliteal aneurysms remains controversial. Debate continues as to when an asymptomatic popliteal aneurysm should be treated and, with concerns regarding the fate of a bypassed popliteal aneurysm and the advent of intravascular stents, what procedure is best? (Galland RB et al., 2008).
Surgical treatment of acute presentation of PAA continues to carry elevated mortality and cardiac morbidity. Although preoperative thrombolysis appears to improve results, the 8% early and 15% late amputation rates with acute presentation remains ominous. Asymptomatic PAAs with thrombus or those with evidence of distal embolization should be considered for repair. PAAs _2 cm should be repaired even without mural thrombus. Early elective repair is recommended to good risk patients with PAAs because operation in this group can be performed with no surgical mortality. A low rate of complications, and no limb loss for asymptomatic patients at 5 years. Endoaneurysmorrhaphy continues to be the gold standard for open repair of PAA (Huang Y et al., 2007).
During recent years, endovascular surgery has become a valid alternative to open repair. Particularly significant progress has been observed in the endovascular treatment of arterial aneurysms, especially of the abdominal aorta. Potentially, PAAs are also treatable by an endovascular approach. Moreover, compared with conventional surgical treatment, the percutaneous endoluminal exclusion of lower-extremity aneurysms as a minimally invasive procedure offers some advantages, including lower blood loss, quicker recovery, and shorter hospital stay (Nagarajan M et al., 2000).
Midterm results with Viabahn endovascular stent-graft exclusion of asymptomatic popliteal artery aneurysms are promising with few complications and continue to match historical results with surgical arterial reconstruction (Rajasinghe HA et al., 2009).
Tielliu et al., reported a series of 57 cases in which endo-vascular popliteal artery aneurysm treatment was performed using Viabahn stent grafts. Technical success was 100%. Primary and secondary patency rates at 2 years were 77% and 87%. Acute ischemia was the indication for PAA repair in five (8.8%) of 57, and only one third of patients received postprocedural antiplatelet or anticoagulation therapy. The only variable found to be associated with success was treatment with clopidogrel (Tielliu IFJ et al., 2005).
3D multilayer stent the most recent device in the endovascular correction of popliteal aneurysm, 3D multilayer stent design reduces the flow velocity within the aneurysm vortex causing thrombus to form & the aneurysm to close so exclude the aneurysm & preserve the circulation (Henry M et al., 2009).