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Sir:FigureWe appreciate the letter from Drs. Azuma, Yamamoto, and Koshima regarding indocyanine green lymphography for donor evaluation. Dr. Koshima's team has done remarkable pioneer work not only in lymphedema microsurgery but also in development of functional indocyanine green imaging of lymphedema.1,2 We are honored to receive such an important commentary. Dr. Azuma et al. have earlier reported that lower extremity lymphedema could be detected by the dermal backflow pattern of indocyanine green lymphography even in asymptomatic limbs.1–3 They compared indocyanine green lymphography and lymphoscintigraphy for early detection of lymph flow dysfunction, and reported that the sensitivity of indocyanine green lymphography is 100 percent compared with 62 percent for lymphoscintigraphy.4 However, to improve the accuracy of lymphoscintigraphic findings in our study, we have used a semiquantitative analysis of the dynamic lymphoscintigraphy (transport index), the sensitivity of which is 97.4 percent and the specificity of which is 90.3 percent according to earlier studies.5 Abnormal patterns on indocyanine green lymphography seem to correlate with histologic findings of the tissue already in the asymptomatic state of lymphedema,4 which clearly may indicate the increased risk of developing clinical lymphedema postoperatively. However, a correlation of the progression of lymphedema with imaging findings has not been established and therefore long-term follow-up studies are needed. Indocyanine green lymphography is a fairly new and infrequently used technique in Europe and in Finland, and we have had only a few experiences using it so far. However, it would definitely offer valuable information concerning donor-site morbidity after lymph node transfer and should be used in combination with other imaging techniques. We are honored that our study about the risks of the new promising surgical technique is considered interesting and has raised such an important discussion. Tiina P. Viitanen, M.D. Erkki A. Suominen, M.D., Ph.D. Anne M. Saaristo, M.D., Ph.D. Plastic Surgery, Turku University Hospital, Turku, Finland DISCLOSURE The authors have no financial interest to declare in relation to the contend of this communication.