Fluorescence Guided Surgery: Hype or Hope

Over the past decade, fluorescence-guided surgery, particularly with the use of indocyanine green (ICG), has gained significant traction. Its rise in popularity stems from its invaluable role in the intricate world of the hepatobiliary system and its adaptability to various oncological procedures, ranging from lymph node mapping in breast, gastrointestinal, gynecological, urological, to head and neck cancers. Furthermore, ICG angiography has found relevance in anastomotic perfusion studies spanning colorectal, esophagogastric surgeries, and even liver transplantation. With such diverse applications, the question arises: Is this groundbreaking technique just a fleeting trend or a beacon of hope for future surgeries?

A closer look at its application within the hepatobiliary system illustrates its profound impact. Historically, surgeons relied on lowcontrast white light visualization. Now, with the advent of ICG fluorescence, there's a remarkable enhancement in visual clarity. When ICG is administered intravenously, the liver promptly exhibits a homogeneous fluorescent pattern termed the early hepatic phase due to the dye's selective uptake by hepatocytes. Within 15 to 30 minutes,
the unchanged ICG is excreted into the bile, revealing the biliary phase—a fluorescence outline of both the intra and extrahepatic biliary tree. As time progresses, the late hepatic phase becomes evident, revealing fluorescent patterns either within or surrounding the liver nodule, contingent upon the liver's parenchymal characteristics. An interesting observation is that a cirrhotic liver continues to exhibit intense fluorescence days post-ICG administration. This property is instrumental in distinguishing liver tumors based on their unique patterns.

The merits of ICG go beyond mere visualization. When introduced intraoperatively post the isolation of hepatic pedicles within the same surgical procedure, ICG brings liver segmentation to the forefront. This sharp demarcation proves indispensable for the anatomical resection of the liver, elevating the precision and thereby the overall surgical outcomes.

Moreover, the innovation of incisionless cholangiography with ICG is a game-changer for pinpointing extrahepatic biliary structures, especially when faced with anatomical anomalies. From our experience, there was a resounding 100% success rate in visualizing the biliary tree using this technique. A detailed breakdown shows that 48% of these structures were discerned prior to dissection, with the remaining 52% identified during the cystic plate clearance and recognition of the cystic duct and common bile duct.

To brand this technique as mere "hype" would be an understatement. The strides made through fluorescence techniques, especially in hepatopancreatobiliary (HPB) surgery, solidify its place as more than a trend—it represents a new dawn in surgical procedures and should be championed as the gold standard in practice.