A systematic review on imaging and diagnostic modalities for the detection, evaluation, and surgical planning of...

The purpose of this systematic review was to evaluate imaging and diagnostic modalities for their roles in (1) diagnosing upper and lower extremity lymphedema, (2) detecting subclinical disease through prospective surveillance, (3) providing anatomical assessment of the lymphatic system, and (4) guiding surgical treatment planning.

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The search included PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus from January 2010 to April 2026. Four reviewers screened 2847 articles using Covidence software. The inclusion criteria were studies that reported original data on one or more imaging modalities and presented diagnostic accuracy, reliability, staging parameters, or impact on surgical planning.

A total of 28 studies were included, comprising four randomized controlled trials, 12 prospective diagnostic studies, six cohort studies, one observational study, and five systematic reviews or meta-analyses. In upper extremity studies, predominantly composed of breast cancer-related lymphedema (BCRL), bioimpedance spectroscopy (BIS) demonstrated a sensitivity of up to 100% and a specificity of 98% for early detection, with the PREVENT trial showing a 59% relative risk reduction in chronic BCRL through BIS-triggered surveillance. Indocyanine green (ICG) lymphography achieved 100% diagnostic accuracy vs 62% for lymphoscintigraphy in early disease, and ultra-high-frequency ultrasound imaging at 70 MHz achieved 94.9% sensitivity for vessel detection. In the lower extremity, magnetic resonance lymphangiography (MRL) at 3.0 T achieved 100% sensitivity for lymph vessel abnormalities vs 79% for lymphoscintigraphy (κ = 0.93 for delayed drainage). Ultrasound imaging achieved 95.5% sensitivity and 92.9% specificity for vessel detection. Two validated ICG-based classifications, saphenous calf thigh and Shinaoka, enabled lower extremity-specific severity staging.

This systematic review identified important differences in the evidence supporting imaging and diagnostic modalities across the four clinical domains evaluated. For diagnosis and subclinical detection, BIS-triggered prospective surveillance for upper extremity lymphedema is supported by randomized controlled trial evidence demonstrating significant reduction in chronic BCRL progression. However, comparable trial data for the lower extremity remains absent. For anatomical assessment, region-specific ICG classification systems (saphenous calf thigh and Shinaoka) address the unique drainage patterns of the lower extremity, while MRL provides comprehensive deep and superficial system visualization across both regions. For surgical planning, the combined use of near-infrared fluorescence lymphangiography and MRL offers complementary information to guide microsurgical interventions.