The use of near infrared fluorescence imaging with indocyanine green for vascular visualization in caudal auricular flaps in two cats

Abstract

Objectives: To describe the use of near infrared fluorescence (NIRF) imaging with indocyanine green (ICG) for vascular visualization in two caudal auricular axial pattern flaps (APF). Animals: Two client-owned cats with upper eyelid masses. Study design: Clinical case report. Methods: Wide surgical excision with enucleation was performed by using a caudal auricular APF for closure. Flap margins and perforating artery location were approximated with anatomical landmarks. The caudal auricular artery origin was then visualized percutaneously by using an exoscope with NIRF camera and light source after a single 2.5-mg dose of IV ICG. Margins were adjusted as required. The flaps were routinely elevated with continued intraoperative visualization of the artery and rotated to complete closure. Results: After IV ICG administration, fluorescence was initially visualized after 15 to 18 seconds and remained visible for up to 26 minutes. The achieved visualization led to flap margin adjustments in cat 1. Both cats recovered with minimal flap congestion, excellent hair regrowth, and no long-term complications (>186 days). Cat 1 experienced 100% flap survival. Cat 2 experienced 10% partial thickness flap necrosis, but revision was not required, and the flap was healed at recheck 85 days postoperatively. Conclusion: The use of ICG for APF vessel visualization prior to and during flap elevation resulted in transcutaneous visualization of the perforating vessel and improved awareness of vessel location intraoperatively. These two cats experienced excellent flap survival without major complications. This report highlights the potential benefits of ICG NIRF in APF for animals undergoing reconstructive surgery.

Case Report: Indocyanine Green-Based Angiography for Real-Time Assessment of Superficial Brachialis Axial Pattern Flap Vascularization in Two Dogs

“…Same limitations were also described by Quinlan et al ( 12 ) in using the VITOM II ICG exoscope on two auricularis oris flaps in cats. Inability to operate under ambient light is challenging for a surgeon, because anatomical structures are not clearly seen while performing (ICG-Angiography), compromising the safety and accuracy of the procedure.…”

“…NIRA performed with either system resulted in clear delineation and identification of the vessel during surgery. The recorded time for clearing the delineation of the vessel was 75 and 93 s, which was slightly longer than the time recorded by Quinlan et al ( 12 ) for NIRA in visualization of auricularis flaps in cats (35 and 52 s). This might be due to species differences, including weight and heart rate at the time of injection.…”

“…In veterinary medicine, NIRA using ICG in skin reconstructive surgery has only been described in two cats for visualization of auricular oris pattern flaps ( 12 ). The authors found the technique useful, and flap outcome was excellent in both cases.…”

Indocyanine-based near-infrared lymphography for real-time detection of lymphatics in a cat with multiple mast cell tumours

“… 20 In addition, a recent case report described IV application of ICG at a dose of 2.5 mg per cat for visualisation of the caudal auricular artery in two cats undergoing reconstruction after tumour resections. 15 …”

“…13,14 So far, the application of ICG-based NIR fluorescence has only been reported for visualisation of the vasculature during reconstructive surgery in two cats. 15 The present report describes the first application of ICG NIR-L in a cat with MCT.…”