Fig. 4. Indocyanine green angiography (ICGA) for toe gangrene. (A) Gangrene of the right second toe is shown (arrow). (B) An ICGA grayscale image after bypass surgery shows no perfusion in the right second toe and adequate perfusion in the surrounding tissue. (C) The objective numbers are shown in an ICGA grayscale image. (D) An ICGA heat-map image shows adequate perfusion in the right foot after bypass surgery.