case_images: PMC11042812_01
case_images: (A) A computed tomographic image showing the location of the stenosis at the P1 segment of the popliteal artery. (B) A digital subtraction angiography showing the eccentric, gradually rising stenosis. (C) An intraoperative image exhibiting the opened adventitial cyst with all gelatinous contents removed.
case_images: 1806-9282-ramb-70-3-e20231482-gf01.jpg
case_images: PMC11042812_01_1806-9282-ramb-70-3-e20231482-gf01.jpg
case_images: f1
case_images: A computed tomographic (CT) angiography was performed, confirming the findings from the sonography and localized the area of obstruction to the P1 segment of the popliteal artery (Figure 1A). By using Doppler ultrasonography and antegrade digital subtraction angiography (DSA), the morphology of the stenosis was established as eccentric, gradually rising from the arterial wall, with a well-developed collateral arterial flow (Figure 1B). Afterward, the adventitial layer of the popliteal artery was incised, revealing a small cavity containing gelatinous material similar to coagulated blood, albeit browner (Figure 1C).
case_images: (A) Fibrous wall of a cystic lesion of the adventitia (hematoxylin-eosin; original magnification, 40x). (B) Alcian-positive mucoid masses diffusely permeating the wall (Alcian blue; original magnification, 40x).
case_images: 1806-9282-ramb-70-3-e20231482-gf02.jpg
case_images: PMC11042812_01_1806-9282-ramb-70-3-e20231482-gf02.jpg
case_images: f2
case_images: Microscopically, the lumen of the cystic structure was not lined with an epithelium layer but filled with mucoid contents (Figure 2A). Histochemically, the wall of the cystic structure was permeated by the mucosubstances positivity in the Alcian blue staining (Figure 2B).