Magnetic resonance lymphography findings across different clinical stages of lower limb lymphedema

Objective

To investigate the findings on lower limb lymphedema using magnetic resonance lymphography (MRL).

Methods

MRL was used to record the lymphatic vessel morphology, distribution of lymphatic vessels, dermal backflow (DBF), and morphology of inguinal lymph nodes in 112 patients (175 affected limbs) with lower limb lymphedema at different clinical stages (according to the International Society of Lymphology staging criteria 2020).

Results

The lymphatic vessel morphology significantly differed at different clinical stages (X² =59.306; P = 0.000). ISL stage I is dominated by “scattered beads” and “branch-like” distribution, ISL stage Ⅱ has tree branch or “capillary-like” distribution, and ISL stage Ⅲ primarily has a capillary pattern and contrast agent accumulation in the foot. There were statistically significant differences in the distribution of lymphatic vessels and DBF in different clinical stages. Distribution of the enhanced lymphatic vessels was distal to the knee in ISL stage I, involved areas below the knee joint or the whole limb in ISL stage II, and involved the whole limb in ISL stage III (X² =44.591; P = 0.000). With the progression of edema, DBF severity increased (X² =76.416; P = 0.000).

Conclusion

MRL revealed the morphology and distribution of lymphatic vessels and detected abnormal inguinal lymph nodes in patients at different stages of lymphedema, which can be used as reference information for surgical treatment.