Background: Functional lymphatic vessels (LVs) are essential for supermicrosurgical lymphaticovenous anastomosis (LVA). Theoretically, the larger the LV, the better the flow. However, large LVs are not readily available. Since the introduction of LVA, no guidelines have been set as to how small a LV is still worthwhile for anastomosis.
Methods: In this longitudinal cohort study, unilateral lower limb lymphedema patients who underwent LVA between March 2016 and January 2019 were included. Demographic data and intraoperative findings including the number and size of LVs were recorded. The cutoff size was determined by receiver operating characteristic (ROC) curve analysis, based on the functional properties of LVs. Clinical correlation was made with post-LVA volume measured by magnetic resonance (MR) volumetry.
Results: A total of 141 consecutive patients (124 females/17 males), with a median age of 60.0 years (56.7 - 61.2) were included. The cutoff size for a functional LV was determined to be 0.50mm (LV0.5) from a total of 1048 LVs. Significant differences were found between the number of LV0.5 anastomosed (0-1, 2-3, and ≧4 LV0.5), the median post-LVA volume reduction (mL) (p < 0.001), and median percentage volume reduction (%) (p = 0.012).
Conclusion: LV0.5 can be a valuable reference for LVA. Post-LVA outcomes can be enhanced with the use of LV0.5 for anastomoses.