Does indocyanine green fluorescence angiography allow earlier detection of vascular compromise in free flaps?

Abstract

Free flaps require close postoperative monitoring to detect vascular thrombosis at an early stage, which is the main cause of failure. Although clinical examination remains the benchmark, it is subjective. Indocyanine green, a fluorescent dye, is a reliable tracer for assessing tissue perfusion. The aim of this study was to assess the contribution of indocyanine green fluorescence angiography in the early detection of vascular compromise in free flaps and to determine whether it enables quicker surgical revision compared to clinical assessment. Data were collected and analyzed retrospectively from patients who underwent free flap reconstruction and indocyanine green angiography monitoring between March 2019 and December 2024, in a single center. Emergency surgical revision was performed only in cases of abnormal clinical monitoring. The study involved 93 free flap reconstructions performed on 87 patients. Eighteen free flaps required revision surgery owing to signs of vascular compromise (revision rate of 19.35%). In 52% of cases, indocyanine green angiography revealed vascular compromise before the appearance of clinical signs. An average delay of 8 h was observed between diagnosis by indocyanine green angiography and the onset of the first clinical signs. Indocyanine green angiography is a reliable method for early detection of microvascular complications, providing a diagnostic advantage of several hours compared to clinical assessment. However, prospective studies are needed to assess the impact of systematic use of indocyanine green angiography in surgical decision-making, surgical revision time, and salvage rate.