Differential Perfusion Patterns of Perforator and Random Flaps Assessed by Indocyanine Green Imaging

Area of Science:

• Plastic Surgery
• Surgical Innovation
• Medical Imaging

Background:

• Indocyanine green angiography (ICGA) is crucial for assessing flap perfusion in reconstructive surgery.
• Current ICGA protocols lack flap-type specific timing, potentially leading to misinterpretation.

Purpose of the Study:

• To compare indocyanine green angiography (ICGA) perfusion dynamics between perforator and random pattern flaps.
• To determine optimal ICGA timing for predicting flap necrosis in different flap types.

Main Methods:

• A rat model was used, with Sprague-Dawley rats randomly assigned to perforator or random flap groups.
• Indocyanine green (ICG) was administered intravenously, with fluorescence imaging at 4-minute intervals.
• Necrosis was assessed on postoperative day 7, with statistical analysis using Mann-Whitney U and log-rank tests with EMICM modeling.

Main Results:

• For perforator flaps, necrosis correlated with ICGA perfusion boundaries between 10-50 seconds, with 50 seconds being the optimal prediction time.
• For random flaps, necrosis aligned with ICGA boundaries from 30-150 seconds, with 150 seconds as the optimal prediction time (p=0.0028).

Conclusions:

• Optimal ICGA timing for flap perfusion assessment differs significantly between perforator and random flaps.
• Implementing flap-specific ICGA assessment windows can improve intraoperative interpretation and reduce false-positive findings.
• Developing tailored ICGA protocols is recommended to enhance decision-making in reconstructive surgery.