Indocyanine green (ICG) fluorescence angiography imaging is useful for visualizing lymph and blood flows. It can be applied in microsurgical reconstruction. In this study, we retrospectively analyzed 8 cases of the usage of ICG fluorescence for intraoperative blood circulation evaluation and discuss 3 typical cases to illustrate its usefulness. In the first case, ICG fluorescence was used following the surgical resection of finger arteriovenous malformation (AVM) to effectively confirm complete AVM resection and circulation of the finger. As a result, the finger was successfully preserved. In the second case, jejunum circulation failure developed after free jejunum transfer. ICG fluorescence revealed limited blood flow to the graft and jejunum; therefore, reanastomosis was performed and the jejunum was preserved. In the third case, unexplainable renal circulation failure developed after kidney transplantation. ICG fluorescence demonstrated the cause of failure to be arterial thrombosis; therefore, arterial reanastomosis with vein grafting was performed and the transplanted kidney survived. ICG fluorescence can be used to directly visualize blood flow, which makes it advantageous over other visualization methods. It is especially useful to clarify the moving circulation dynamics, small color difference between flaps, and causes of circulation failure.
