Membranous obstruction of the inferior vena cava.
D000328:Adult; D000792:Angiography; D001401:Azygos Vein / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D014463:Ultrasonography; D014652:Vascular Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging*