High‐Frequency Ultrasonography for Classifying Lymphatic Sclerosis Types in Patients With Lymphedema

BACKGROUND: To identify predictive ultrasonic factors and establish cutoff values for assessing sclerosis severity and selecting appropriate lymphatic vessels for lymphovenous anastomosis (LVA). METHODS: We enrolled 22 patients with extremity lymphedema undergoing LVA (53 lymphatic vessels). Sclerosis severity was determined preoperatively by ultrasonography and intraoperatively using a surgical microscope; the findings were stratified by NECST (normal, ectasis, contraction, and sclerosis type) classification. Demographic and ultrasonographic data, including lymphatic vessel inner and outer diameters (Id and Od, respectively), Id/Od ratio, and wall thickness, were analyzed. RESULTS: Although NECST classifications for ultrasonographic and surgical observations exhibited discrepancies, ultrasound findings showed high overall accuracy (71.7%), with strong correlation (r = 0.652) and moderate agreement (k = 0.554) with intraoperative results. For ultrasound-based classification, Id and Id/Od ratio of 0.43 mm and 34.1% were the suggestive values for predicting ectasis type, with the area under the curve (AUC) values of 0.843 and 0.842, respectively. For surgical evaluation-based classification, Id and Id/Od ratio of 0.269 mm and 41% were the suggestive values for predicting ectasis type, with both AUC values > 0.8. These results were significant (p < 0.05). CONCLUSION: Ultrasonographic parameters could help identify ectasis type of lymphatic vessels in patients with extremity lymphedema.