Investigation of lymphatic pathway remodeling in the supraumbilical region after abdominoplasty

Background: Abdominoplasty is a surgical procedure that reshapes the anterior abdominal wall both aesthetically and functionally and involves extensive skin–subcutaneous tissue dissection. The wide flap elevation and skin–subcutaneous dissection performed during abdominoplasty may disrupt the continuity of lymphatic flow in this region and lead to alterations in drainage patterns. In the superficial lymphatic drainage of the anterior abdominal wall, the level of the umbilicus is considered a theoretical watershed between the axillary and superficial inguinal nodal basins. In this study, we aimed to evaluate the lymphatic drainage of the supraumbilical skin flap in patients undergoing classical lipoabdominoplasty in the preoperative and postoperative periods using dynamic lymphoscintigraphy and SPECT/CT, and to demonstrate the patterns of lymphatic remodeling. Materials and Method: This prospective clinical study was conducted in 15 female patients scheduled for classic lipoabdominoplasty. Preoperatively, the abdominal skin was divided into four quadrants (right upper, left upper, right lower, left lower). Intradermal Tc-99m nanocolloid was injected into each quadrant; drainage pathways were assessed with dynamic lymphoscintigraphy, followed by evaluation of axillary and inguinal lymph node uptake using SPECT/CT. At postoperative month 6, the same protocol was repeated with injections performed in a manner corresponding to the supraumbilical skin flap proximal to the incision line. Pre- and postoperative lymphatic drainage patterns were compared, and potential associations with reduction mammoplasty history and other clinical variables were analyzed. Results: The median age of the patients was 37 years (Q1–Q3: 34–40), and all were female. In the preoperative period, 93.3% of upper quadrant injections drained as expected to the axillary lymph nodes bilaterally, while all lower quadrant injections (100%) drained to the inguinal lymph nodes. At postoperative month 6, lymphatic drainage from the supraumbilical region continued to the axilla in 73.3% of cases on both sides, whereas in 26.7% variant patterns such as dual drainage (axillary + inguinal), delayed transit, collateral deep drainage, or complete redirection to the inguinal basin were observed. However, in dichotomous normal/abnormal classification, the McNemar test did not reach statistical significance (p=0.248; OR=0.143; 95% CI: 0.077–1.000). The association between a history of reduction mammaplasty and the presence of abnormal/alternative drainage patterns was statistically significant (Haldane OR: 34.2; p=0.011). No significant relationship was found between lymphatic drainage changes and other surgical or clinical variables. Conclusion: After classic lipoabdominoplasty, axillary drainage of the supraumbilical skin flap is preserved in most patients; however, a clinically relevant subgroup develops new drainage patterns (dual drainage, collateralization, delayed transit, and inguinal redirection). These findings demonstrate the remodeling capacity of the lymphatic system after abdominoplasty and indicate that truncal lymphatic drainage is a dynamic structure sensitive to surgical intervention. In addition, individualized lymphatic mapping with lymphoscintigraphy and/or SPECT/CT may be clinically useful when planning sentinel lymph node mapping and staging for abdominal wall malignancies in patients with a history of abdominoplasty. In contemporary oncology, the increasing adoption of sentinel lymph node biopsy (SLNB)–based nodal staging and surveillance, along with the shift of completion lymph node dissections to more selected indications due to their morbidity, enhances the clinical value of accurate lymphatic mapping in patients with a history of abdominoplasty. Keywords: Abdominoplasty; lymphoscintigraphy; lymphatic drainage; lymphatic remodeling