Lymphatic Ultrasound in Longitudinal Decision-making for Lymphedema: A Narrative Review Integrating Conservative and Surgical Management.

Background: Lymphedema is a chronic and progressive condition that requires long-term reassessment and adaptation of treatment strategies. Although conservative therapy and surgical interventions such as lymphaticovenular anastomosis have advanced, imaging findings are not consistently integrated into longitudinal treatment decision-making, including treatment selection, timing, and target prioritization. Methods: This narrative review synthesizes current evidence and practice-related concepts regarding lymphatic ultrasound. Topics include lymphatic vessel characterization, differentiation from veins, subcutaneous tissue evaluation, and elastography. Particular emphasis is placed on how these findings may inform conservative management, surgical planning, and serial reassessment during the disease course. Results: Lymphatic ultrasound enables repeated, noninvasive evaluation of both lymphatic vessels and surrounding subcutaneous tissues within the same examination. When interpreted using structured approaches such as NECST (normal, ectasis, contraction, and sclerosis)-aligned vessel assessment and D-CUPS, serial ultrasound may help clinicians adjust compression strategies, identify potential windows for lymphaticovenular anastomosis, reassess treatment targets beyond the affected limb segment, and support multidisciplinary communication during follow-up. The principal conceptual contribution of this review is the integration of previously described vessel-based and tissue-based ultrasound findings into a longitudinal, practice-oriented decision framework. Conclusions: Beyond its role as a one-time diagnostic adjunct, lymphatic ultrasound may function as a practical longitudinal assessment tool in integrated lymphedema management. By linking vessel status, tissue phenotype, conservative optimization, and surgical decision-making across the disease course, this approach may support more adaptive and patient-centered care. However, broader external validation will be necessary before this framework can be considered widely generalizable.