Divergent vascular courses in the submental lymph node flap revealed by cadaveric study

Vascularized submental lymph node (VSLN) flap transfer is a promising treatment for lymphedema, yet its venous anatomy remains underexplored. This study investigated variations of the submental artery and vein and the courses of hilar arteries and veins connecting lymph nodes in 40 VSLN flaps from 20 Thai cadavers. Colored latex was injected in both sides of the internal carotid arteries, external carotid arteries, internal jugular veins, and external jugular veins of each cadaver. The mandibles were removed en-bloc and then sliced coronally for investigation under stereomicroscopy. The submental artery and vein followed a parallel course in 80% (n = 32) of flaps, predominantly deep to the anterior belly of the digastric muscle (ABDM). In contrast, hilar arteries and veins exhibited divergent courses, with 13.7% (n = 21) of nodes draining into the anterior jugular vein, 30.1% (n = 46) into the facial vein, and 49.7% (n = 76) into the submental vein. These findings highlight the previously underrecognized role of the anterior jugular vein and confirm the critical contribution of the facial vein. Dissection techniques for VSLN flap have been recommended to increase treatment efficacy and decrease risk of venous congestion: (1) include ABDM in the flap if the flap area superimposed this muscle; (2) include the facial artery and vein in continuity with submental vessels; and (3) may include the anterior jugular vein as an additional venous pedicle.