Fluorescent indocyanine green angiography: Preliminary results in microsurgery monitoring.

Introduction: Pedicled flaps and free-tissue transfer flaps are used routinely to reconstruct hard and soft tissue defects in head and neck, limb, hand, thoracic and abdominopelvic reconstructive surgery. But failure remains a constant concern, particularly in free-tissue transfers. Usually failure is due to blood supply compromise. Indocyanine green (ICG), a fluorescent dye is a suitable tracer for vessel perfusion. The objective of this study is to evaluate the fluorescent indocyanine green angiography (FA ICG) in free flaps procedures.

Materiel And Methods: Patients who had microsurgical flap reconstruction were included during the study period in a single center. The FA ICG was used at specific times. Intra-veinous injections of 0.1mg/kg of INFRACYANINE (concentration 2.5mg/mL) were done intraoperatively. The Fluobeam device programmed on sensitivity and mapping to interpret the data, was used. These different injections allowed to checked skin paddle perforators vessels, osseous perforators vessels, arterial and venous patency after anastomosis and the cutaneous, muscular and osseous perfusion.

Results: A total of 12 patients enrolled were 10 males and 1 female. Their mean age was 54.5 years (range 25-75 years). Of the 12 flaps, 8 were free flaps with 4 fibular flaps (3 for mandibular reconstruction and one for femur reconstruction); 2 radial forearm flaps for maxillary reconstruction; one latissimus free flap for tibia skin coverage and one retroauricular fasciocutaneous free flap for thumb skin coverage. We got to modify specific steps during surgery with 8 patients by using the FA ICG to anticipate potential complications: modifying the draw of the skin paddle, recut of this paddle, modifying the osteotomies, re-doing the anastomosis or modifying the position of the pivot point.

Discussion: Evaluation of microvascular flap perfusion is still based on subjective clinical features. Clinical monitoring is observer-dependent and does not allow information sharing, test reproducibility, and consistent postoperative follow-up. The successful of salvage rate is linked to the delay between the onset of ischemia and its clinical assessment. FA ICG could be a reliable method for monitoring free-tissue transfers. This technique is objective, non invasive and facilitate a complex reconstructive procedure to augment is liability. This technique may be used such a pedagogical tool for young practitioners in their first microsurgery procedures.