a 67-year - old male , having a history of diabetes mellitus and classified as a heavy smoker ( 50 pack - years ) , presented with left thigh pain that had been aggravated in sitting or squatting positions for the previous four months .
the patient felt tenderness on the mass - like lesion on the left thigh , which was large and pulsatile .
a computerized tomography angiography image revealed a giant aneurysm of the left popliteal artery and mild atherosclerotic aneurysmal change of the right popliteal artery ( fig .
there were mild atherosclerotic calcifications in the lower abdominal aorta and iliofemoral arteries without significant aneurysmal changes .
surgery was performed separately from upper and lower medial approaches to allow for a direct view of the aneurysm under spinal anesthesia .
the line of the incision ran from four fingerbreadths above the adductor , opening downwards and backwards to a little behind the medial femoral condyle and avoiding the greater saphenous vein .
the deep fascia was incised , and the anterior border of the sartorius muscle was identified .
the muscle was displaced backwards to reveal the thicker aponeurosis of the adductor canal running into the tendon of the adductor opening .
a lower medial approach was made along the posterior tibial border from the lower aspect of the medial condyle , avoiding the greater saphenous vein .
the deep fascia was incised and the medial head of the gastrocnemius muscle was displaced backwards .
the loose popliteal fat was dissected free from the vascular bundle to reveal the vein with the popliteal artery .
since the aneurysm was too large and long ( 66 cm ) to dissect between the adductor opening and the sartorius muscle , we could not clamp the distal and proximal end of the aneurysm ( fig .
we performed a bypass from the common femoral artery ( end - to - side ) to the distal popliteal artery ( end - to - side ) below the knee , using the autologous greater saphenous vein ( fig .
an exclusion of the aneurysm by double ligation back and forth using black silks was performed at the sites of anastomoses ( the proximal superficial femoral artery and the distal popliteal artery ) following the identification of the distal pulse . while the patient obtained good pulsation of the posterior tibial artery and the dorsalis pedis artery postoperatively , the popliteal artery aneurysm lost pulsatile movement immediately .
the patient could walk five days after the operation because of severe postoperative wound pain .
however , an immediate follow - up angiography showed a patent vein graft and a completely thrombosed aneurysm ( fig .
the patient was discharged 19 days after the operation , and was able to walk without ambulatory equipment at that time .
in addition , scanty delayed bleeding from the dissected medial gastrocnemius muscle occurred two months after the operation , and we performed a hematoma evacuation and a primary closure . at three months ' follow - up ,
the previously palpable aneurysm had reduced in size and the tenderness on the aneurysm had disappeared .
popliteal artery aneurysms ( paas ) are rare , with a prevalence of < 0.01% reported in hospitalized patients .
it was recently estimated that < 0.1% of the overall population suffers from paa and the percentage is increased to 1% for the 65- to 80-year age bracket .
these aneurysms are the most frequently diagnosed and account for up to 70% of all the peripheral arterial aneurysms .
the normal diameter of the popliteal artery is influenced by the patient 's gender , age , and body surface , and is 6.00.7 mm for women and 6.80.8 mm for men .
paa is defined as a widening of the popliteal artery by > 50% of the original diameter .
a giant paa , however , has not been defined by size criteria and has been reported only sporadically .
paas are most commonly caused by atherosclerosis , but there are some other causes , particularly in younger patients .
some of these include entrapment syndrome with pre- or post - stenotic arterial enlargements and pseudoaneurysms ( iatrogenic or post - traumatic ) , mycotic aneurysms , and inflammatory arteritis ( collagenoses or rheumatic diseases ) .
two case reports of paa in korea have been published : a case of bilateral popliteal artery entrapment syndrome   and one of traumatic popliteal artery pseudoaneurysm , developed during a soccer game .
the main complications of paa include distal embolization , local compression increasing the risk for popliteal vein thrombosis , and thrombotic obstruction leading to a high risk of limb loss .
rupture is an uncommon complication affecting less than 2% of paa . for these reasons ,
elective surgical management of asymptomatic aneurysms larger than 20 mm has been advocated by several authors .
indications for interventions are well defined for patients who present with acute ischemia and for most of those who have chronic ischemic symptoms .
patients with severe claudication , resting pain , and tissue loss are considered for elective repair , as are patients who have symptoms of local compression .
indications for asymptomatic patients and for those with mild - to - moderate claudication are less well defined .
factors affecting the decision on surgery include the rate of development of symptoms , aneurysm size , mural thrombus , evidence of previous thromboembolism , risk from surgical repair , and long - term surgical outcome .
the most commonly performed surgical technique for paa repair is aneurysm exclusion and autologous venous or polytetrafluoroethylene bypass grafting , and this technique remains the gold standard .
open surgical repair is composed of a medial approach with ligation and resection of the aneurysm , along with above - knee to below - knee bypass , and a posterior approach with direct visualization and resection of the aneurysm and reconstruction with interposition of a vein or prosthetic graft .
endovascular repair with a stent graft is a minimally invasive alternative approach to that of conventional repair .
potential long - term problems , such as stent - graft migration and stent fracture with occlusion , are possible . a major concern when using this technique for the popliteal artery is that a flexion joint is crossed . the great mobility of the popliteal artery , along with the risk of device rotation , twisting , and kinking , remain a problem .
the various devices employed for the stent - graft are relatively stiff and not ideally designed to be used in a small artery , which is subject to repetitive flexion and extension . the hemobanhn / viabahn graft ( wl gore & associates inc . , flagstaff , az , usa ) offers good flexibility and radial stiffness , minimizing the risk of kinking during knee joint flexion , and it is the most used graft for endovascular paa repair . in korea , the endovascular stent - graft has been used since february 2012 .
they suggest the following : 1 ) early repair , before ischemic symptoms , yields better results ; 2 ) the greater saphenous vein seems to have better durability than that of a prosthetic graft ; and 3 ) early and mid - term patency of the popliteal artery treated by open surgery and endovascular repair has similar results , but the endovascular repair needs frequent re - interventions during the early period .
an endovascular procedure using a stent - graft has recently come into use , and is thought to be a reasonable option for treating paa . in the case of giant paa , however , there is no established standard for treatment .
we report the first case of successful treatment of a giant paa through open surgical repair , using the saphenous vein graft .
 while popliteal artery aneurysm is the most common form of peripheral artery aneurysm , it is a rare condition in the general population . 
 furthermore , a giant popliteal artery aneurysm has not previously been reported in korea . a 67-year - old male presented with left thigh pain that had begun 
 4 months earlier and was aggravated when in a sitting position . 
 we found a giant aneurysm on the left popliteal artery and performed a bypass from the common femoral artery to the distal popliteal artery below the knee , using the autologous greater saphenous vein , and excluded the aneurysm at the sites of anastomoses . 
CASE REPORT
DISCUSSION