Background
Recent years have witnessed marked increase in the implementation of near-infrared (NIR) technology with fluorescent dyes to assess vascular perfusion in microsurgery. Whether it is of also clinical importance in forming well perfused anastomoses is unclear. The aim of this study was to review clinical value of NIR indocyanine green imaging (NIR-ICG) for colorectal anastomotic safety.

Material and Methods
A Pubmed® search was undertaken using keywords “near-infrared”, “indocyanine green”, “anastomosis” and “anastomotic” in February 2014. Studies retrieved were then manually checked to assess their eligibility for inclusion. Papers clinically examining colorectal anastomotic perfusion using NIR-ICG were reviewed.

Results
The first search retrieved 38 articles, of which three investigated NIR-ICG in patients undergoing low anterior resection and hence included in the study. Of these, one was a feasibility study. Another study assessed perfusion of colonic and rectal bowel segments to determine the transection lines before the anastomosis was done. In three patients colonic transection line moved proximally after assessment by NIR-ICG. No changes of the rectal transection line occurred. The third study examined anastomotic perfusion after formation of anastomosis. Four patients were found to have unsatisfactory anastomotic perfusion, of whom two developed perianastomotic collection as detected by CT scan. Both patients were managed conservatively. There were no studies investigating perfusion of colocolic/ileocolic anastomosis using NIR-ICG.

Conclusion
NIR-ICG shows promise for the assessment of colorectal anastomotic safety in the future. However, published data on this issue is scarce and needs to be strengthened to make a clearer conclusion.