Disease in the femoral triangle: sonographic appearance.

Twenty-nine patients had sonographic evaluation of the femoral triangle because of pain or swelling. The entities diagnosed by sonography were abscesses (seven), cellulitis (three), hematoma (five), nodal enlargement (four), aneurysm of the femoral artery (three), and thrombophlebitis of the femoral vein (seven). Both abscesses and hematomas were poorly defined primarily anechoic masses. Soft-tissue swelling but no distinct masses were present in cellulitis, and all cases of adenopathy were well defined anechoic masses. Aneurysms were also primarily well defined, pulsatile, anechoic masses except mycotic aneurysm, which may present as a primarily solid mass. The sonographic features of thrombophlebitis which has received scant attention in the sonographic literature are stressed. Findings suggest a dilated anechoic vein is characteristic of this entity. Although the sonographic findings or clinical data of many of these entities may be nonspecific, when used in combination, the correct diagnosis can usually be obtained.