A new indocyanine green fluorescence lymphography protocol for diagnostic assessment of lower limb lymphoedema

Introduction: The lower limbs are a common body site affected by chronic edema. Imaging examination of the lymphatic system is useful to diagnose lymphoedema, identify structural changes in individuals, and guide interventional strategies. In this study, we used a protocol combining indocyanine green (ICG) lymphography and ICG-guided manual lymphatic drainage (MLD) for the diagnostic assessment of lower limb lymphoedema.Materials and methods: Patients with lower limb lymphoedema were divided into three groups by their medical history: primary, secondary cancer-related, or secondary non-cancer-related. ICG lymphography was conducted in three phases: initial observation, MLD to accelerate ICG dye transit and reduce imaging time, and imaging data collection. Lymphatic drainage regions were recorded, and the MD Anderson Cancer Center ICG staging was applied. We collected routine lymphoedema assessment data, including limb volume and bioimpedance spectroscopy measurements.Results: Three hundred and twenty-six lower limbs that underwent ICG lymphography were analyzed. Eight drainage regions were identified. The ipsilateral inguinal and popliteal were recognized as the original regions, and the remaining six regions were considered compen-satory regions that occur only in lymphoedema. More than half of the secondary cancer-related lower limb lymphoedema (57.6%) continued to drain to the ipsilateral inguinal region. The inci-dence of drainage to the ipsilateral inguinal region was even higher for the primary (82.8%) and secondary non-cancer-related (87.1%) groups. Significant associations were observed between cancer-related lymphoedema and the presence of compensatory drainage regions.Conclusions: We proposed a prospective ICG lymphography protocol for the diagnostic as-sessment of lower limb lymphoedema in combination with MLD. Eight drainage regions were identified, including two original and six compensatory regions.(c) 2022 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Pub-lished by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Automated summary

Using a combination of ICG lymphography and ICG-guided manual lymphatic drainage, this study conducted diagnostic assessment of lower limb lymphoedema. Eight drainage regions were identified, including two original regions and six compensatory regions. Differences in drainage patterns were observed among different types of lymphoedema.