From Shadow to Light

Abstract

Background. Correct recognition of the extrahepatic bile ducts is thought to be crucial to reduce the risk of bile duct injuries during various laparoscopic procedures. Image-enhanced laparoscopy techniques, utilizing various optical modalities other than white light, may help in detecting structures “hidden” underneath connective tissue. Methods. A systematic literature search was conducted of studies describing image-enhanced laparoscopy techniques for visualization of the extrahepatic bile ducts. Results. In all, 29 articles met inclusion criteria. They describe various techniques in the animal or human setting, including autofluorescence imaging, drug-enhanced fluorescence imaging, infrared thermography, and spectral imaging. This review describes these various techniques and their results. Conclusion. Image-enhanced laparoscopy techniques for real-time visualization of extrahepatic bile ducts are still in its infancy. Out of the techniques currently described, indocyanine green–enhanced near-infrared fluorescence laparoscopy has the most mature results, but other techniques also appear promising. It can be expected that in the future, image-enhanced laparoscopy might become a routine adjunct to any white-light laparoscopic operation near the hepatic hilum.