To explore the application of high-frequency ultrasound combined with shear wave elastography (SWE) in assessing the efficacy of lymphatic venous anastomosis (LVA) in the treatment of secondary lymphedema.

This prospective study included 34 patients with secondary lymphedema who underwent LVA at the Department of Vascular Surgery, Henan Provincial People’s Hospital between August 2023 and August 2024. Limb circumference measurement, bioelectrical impedance analysis (BIA), and high-frequency ultrasound combined with SWE were performed both before and after treatment. We analyzed and compared the dermal shear wave velocity and thickness, as well as the subcutaneous tissue shear wave velocity and thickness, at multiple limb measurement points pre- and post-treatment. Furthermore, Pearson or Spearman correlation tests were used to analyze the correlation between the improvement rates of the ultrasound-derived parameters after treatment and the improvement rates of both the percentage of excess volume (PEV) in the affected limb and the extracellular water-to-total body water ratio (ECW/TBW).

Significant differences were observed in dermal thickness and shear wave velocity (SWV) of both the dermis and subcutaneous tissue layer between the healthy and affected limbs (P<0.001). Following LVA, PEV and ECW/TBW of the affected limb significantly decreased P<0.001); dermal SWV significantly decreased at all measurement points (P<0.001); subcutaneous tissue layer SWV significantly increased (P<0.001); and dermal thickness changes were not statistically significant (P>0.05). Positive correlations were found between ΔPEV and Δ(ECW/TBW) (r>0.7, P<0.001), between the change rate of dermal SWV and ΔPEV at each measurement point (r =0.392-0.709, P<0.05), and between the change rate of dermal SWV and Δ(ECW/TBW) (r =0.346-0.687, P<0.05) Negative correlations were found between the change rate of subcutaneous tissue SWV and ΔPEV, with higher correlations observed at planes near the knee (10 cm below the superior patellar border and the superior patellar border plane) and the calf mid-point plane (r<-0.5, P<0.01), and between the change rate of subcutaneous tissue SWV and Δ(ECW/TBW), with higher correlations observed at points on the knee-related planes and calf mid-point plan than at thigh segment points (r<-0.41, P<0.05). The change rate of subcutaneous tissue thickness was positively correlated with both ΔPEV and Δ(ECW/TBW) (r =0.316-0.708, P<0.05).

Following LVA in patients with secondary lymphedema, decreased SWV in the dermis and thinning of the subcutaneous tissue layer were observed. High-frequency ultrasound combined with SWE effectively quantifies these changes across different tissue layers before and after treatment, providing valuable ultrasonographic evidence for postoperative follow-up and treatment assessment.