Studying Deep Inferior Epigastric Perforator Flap Perfusion Using the Isolated-perfused Human Abdominal Skin Flap

This study investigated dynamic deep inferior epigastric artery perforator flap perfusion in an ex vivo perfusion model using dynamic infrared thermography (DIRT) and indocyanine green fluorescence angiography (ICG-FA) and compared the results with static perfusion imaging using color dye injection technique and computed tomography angiography (CTA).

Individual vessels were perfused with modified Krebs-Henseleit buffer (pH 7.4) in an isolated-perfused human abdominal skin flap perfusion model. Their perfusion patterns were sequentially evaluated with all 4 imaging techniques.

Perfusion patterns of 37 vessels in 19 hemi-deep inferior epigastric perforator (DIEP) flaps and 1 cross-midline DIEP flap were examined. DIRT and ICG-FA measurements of perforators displayed similar perfusion patterns and corresponded well with the colored skin area after dye injection. CTA showed equivalent 3-dimensional images of the selected perforator. Lateral and medial perforators had variable perfusion patterns but often drained into the superficial veins; and sometimes perfused both the medial and lateral flap zones. CTA revealed true anastomosis connecting 2 different perforators, whereas the other imaging modalities showed a large overlap on the skin. DIRT showed that the venous drainage can be rerouted between the ipsilateral and contralateral superficial inferior epigastric vein when 1 superficial inferior epigastric vein is obstructed in the cross-midline DIEP flap.

DIRT and ICG-FA provided comparable and reproducible results that could easily be related to the skin perfusion area in the color dye experiments and CTA 3-dimensional reconstruction, supporting the use of DIRT and ICG-FA for evaluating and investigating DIEP flap perfusion in clinical and research settings.