Dynamic lymph flow imaging in patients with oedema of the lower limb for evaluation of the functional outcome after autologous lymph vessel transplantation: an 8-year follow-up study

The purpose of this study was to monitor the functional outcome of microsurgical intervention on lymph drainage by means of non-invasive, readily available lymphoscintigraphy. Eight patients with primary or secondary lymphoedema of the lower limb were investigated before and for 8 years after autologous lymph vessel transplantation. For scintigraphy, technetium-99m labelled nanocolloid was subcutaneously injected into the first interdigital space of the affected limb. Sequential images were acquired up to 6 h p.i.; for semiquantitative evaluation a numerical transport index was established by assigning scores of up to 9 on each of five criteria: lymphatic transport kinetics, distribution pattern of the radiopharmaceutical, time to appearance of lymph nodes, visualisation of lymph nodes and visualisation of lymph vessels/grafts. Ti values <10 were considered normal. In all eight patients, lymphatic function significantly (P≤0.01) improved after microsurgical treatment. Permanent function of vessel grafts was indicated by persistently low Ti values during the entire observation period, impressively demonstrating the success of this complex microsurgical technique. Patients with scintigraphic visualisation of the vessel graft (n=2/8) showed a substantially better postoperative outcome than those without visualisation of the vessel graft. The findings indicate that lymph vessel transplantation significantly improves lymph drainage in patients with primary or secondary lymphoedema of the lower limb. Thus, lymphoscintigraphy is helpful not only in planning microsurgical treatment but also in monitoring the postoperative outcome. (orig.)