The Relationship Between Clinical and Indocyanine Green Staging in Lymphedema

Background: Multiple staging systems for classifying the severity of lymphedema exist. The International Society of Lymphology (ISL) stage is considered standard for clinical reporting, but the relationship between clinical and functional/imaging stage remains poorly defined. Materials and Methods: We reviewed the prospectively collected data of all patients who underwent physiologic lymphedema surgery for a 3-year period by the senior author. Patients who underwent preoperative clinical staging with limb volume calculations and intraoperative indocyanine green (ICG) staging were included. Correlations were examined between ISL stage, ICG stage, and preoperative volume difference. Results: A total of 212 patients met inclusion criteria. ISL stage and preoperative volume difference had a Pearson correlation coefficient of 0.579 [p < 0.001, 95% confidence intervals, CIs (0.479-0.664)]; ICG stage and preoperative volume difference had a Pearson correlation coefficient of 0.338 [p < 0.001, 95% CIs (0.204-0.460)]; and ISL stage and ICG stage had a Pearson correlation coefficient of 0.254 [p < 0.001, 95% CIs (0.114-0.383)]. Conclusion: Clinical ISL stage does not correlate well with ICG stage in patients undergoing physiologic lymphedema surgery.