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Updated: Mar 27, 2026

Engineered Vascularized Muscle Flap
Published on: January 11, 2016
Proposed pathway and mechanism of vascularized lymph node flaps
Ran Ito1, Jonathan Zelken2, Chin-Yu Yang3
1Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taoyuan, Taiwan, ROC; Department of Plastic and Reconstructive Surgery, Kyoto University, Kyoto, Japan.
Objective:
To investigate the pump mechanism and pathway of lymph transit in vascularized lymph node flaps.
Background:
Microsurgical treatment of lymphedema with vascularized lymph node transfer can improve signs and symptoms of disease, but the pathways and mechanisms of these flaps warrant further exploration.
Methods:
(Animal model) 72 flaps were raised in 18 rats: 36 groin flaps contained lymph nodes (LN), 36 deep inferior epigastric artery perforator flaps did not (non-LN). Indocyanine green (ICG) was added into normal saline (NS), 1%, 3%, 5%, 7% and 10% albumin. Three rats were assigned to each group. LN and non-LN flaps were submerged in solution and surveyed for venous fluorescence. In the 7% albumin and NS groups, volumetric change of solution was measured. (Human model) A similar experiment was performed in humans using five submental LN flaps.
Results:
(Animal model) Fluorescence was detected in the venous pedicle of LN flaps submerged in 5%, 7% and 10% albumin, and half of flaps submerged in 3% albumin. Fluorescence was not detected in LN node flaps submerged in ICG-containing NS or 1% albumin solution. Fluorescence was not detected in non-LN flaps. There was greater volume reduction with LN flaps than non-LN flaps (p<0.001). (Human model) Fluorescence was detected in the venous pedicle of all flaps immersed in lymph.
Conclusions:
ICG fluorescence was detected in the venous pedicle of rat and human LN flaps submerged in lymph or albumin when the concentration was greater than 3%. Based on these results, a pathway for lymphatic uptake is presented.
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