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Paper text:
a 57-year - old man was referred to our department because of a recent aggravation of sensations of coldness , tingling , and pain in the right leg .
he had right calf pain for 4 months , which was exacerbated by walking a distance of 500 meters , and occasional nocturnal stabbing leg pain for 1 month .
he had a medical history of hypertension and operation for a soft tissue mass in the medial side of right knee .
physical examination revealed pallor , poikilothermia , decreased sensitivity on the pin prick test , and no palpable pulse below the popliteal artery .
he had no remarkable findings in cbc and chemistry except for an elevated ast of 78
ct angiography showed severe narrowing of the right popliteal artery , which was compressed by a multi - loculated cystic mass with a largest diameter of 3 cm ( fig .
1 ) . we decided to perform a surgical resection of the lesion because we were concerned about fracturing of the endovascular stent in the frequently bent area . under spinal anesthesia
he was positioned prone for a posterior approach . when the popliteal artery was exposed , a cystic mass filled with a jelly - like material encased the artery .
pulse was palpable in the proximal part of mass but not in the distal part . in order to facilitate the dissection and make the relationship between mass and arterial lumen clear , vertical arteriotomy was performed after applying proximal and distal vascular clamps .
2 ) . complete excision and arterial repair with autologous vein patch was done to prevent stenosis of the arteriotomy site .
pathologic findings confirmed cystic adventitial disease ( cad ) , based on the presence of multiple mucinous foci of degeneration in the vascular wall ( fig .
he was discharged on the fifth postoperative day , but continued to complain of paresthesia during outpatient follow - up . on the postoperative ct angiography ,
paresthesia gradually improved with symptomatic treatment for neuropathic pain and finally disappeared on the sixth postoperative month .
cad is so rare a disorder that less than 400 cases have been reported in the literature .
the first case of cad involved external iliac artery and was reported by atkins and keys in 1947 . because cad is commonly presented with intermittent claudication , popliteal artery entrapment syndrome , buerger 's disease , and popliteal artery aneurysm should be differentiated .
however , cad usually develops in young and middle - aged men without evidence of atherosclerosis . in some cases ,
the symptoms have a sudden onset and have a short duration of days to weeks rather than years .
the disease mainly affects popliteal arteries ( about 85% of cases ) and , more rarely , the common femoral , external iliac , radial , and ulnar arteries .
ischemic neuropathic symptoms such as burning pain , coldness , or paresthesia may be present . sustained ischemic neuropathic symptoms after revascularization were noted in this case .
if the arterial patency is confirmed by radiologic studies during postoperative follow - up , pain - relieving medication and close observation could be sufficient to address residual symptoms .
the etiology of cad remains to be elucidated , but four hypotheses have been proposed .
the ganglion theory assumes that synovial cysts , which track along vascular branches , are finally settled in the adventitia of major vessels . in the systemic disorder theory ,
lastly , the developmental theory suggests that mucin - secreting mesenchymal cells from nearby joints erroneously migrate to adjacent adventitia during the embryogenesis period .
the patient in this case study showed cysts in the ct angiography of the knee joint at the time of diagnosis in addition to a history of resection for a soft tissue mass in the nearby joint area .
treatment options for cad have been described , including percuatenous aspiration , open incision and cyst enucleation , endovascular stent insertion , excision of the cyst with autologous vein graft reconstruction , and bypass surgery .
percutaneous aspiration is not effective in most of the cases because the content of the cyst is viscous , consisting of mucoproteins and mucopolysaccharides .
endovascualr stent placement is generally not advised because cad patients are often young and stenting of the popliteal artery is not a durable therapy , due to intimal hyperplasia or stent fracture .
angioplasty   and even spontaneous resolution of cad has been reported , such experiences are limited and surgical resection is generally considered to be an acceptable treatment . in summary , we successfully treated cad with complete resection and autologous vein patch repair without any complications .
cystic adventitial disease is rare , but it is one of the well - recognized causes of non - atherosclerotic arterial stenosis or obstruction . despite one of its most common symptoms being chronic intermittent claudication , it may be misdiagnosed as arterial embolism when presented with acute ischemic symptoms . 
 surgical resection is recommended because of recurrence or a low success rate with aspiration or endovascular stent . 
 we performed resection and repair with autologous vein patch for cystic adventitial disease of the popliteal artery of a 57-year - old man presenting with pain , pallor , and paresthesia , without any postoperative complications or recurrence .