Fluorescence Guidance Reduces Operative Time for Sentinel Lymph Node Biopsy in the Head and Neck

ABSTRACT Objective Prior studies have demonstrated the feasibility of fluorescently labeled tilmanocept for sentinel lymph node biopsy (SLNB) in the oral cavity. We evaluated the added value of fluorescently labeled tilmanocept in sentinel lymph node biopsy (SLNB) of the oral cavity compared to gamma probe. Methods Healthy male New Zealand white rabbits received oral cavity injections of radioactive (Technetium 99m) and fluorescently (IRDye800) conjugated tilmanocept followed by either fluorescence guided ( n = 14) or gamma probe guided ( n = 14) SLNB performed 1 h, 48 h, or 5 days postinjection. Duration of the SLNB performed by two individuals was measured and compared using the two methods. Results Fluorescence guidance resulted in a 1.8‐fold reduction in time of SLN removal (median 104 vs. 191 s, p = 0.05). For the fluorescence guided SLNB, 7.1% (1 of 14) had nonsentinel node tissue removed prior to the correct identification of the SLN, whereas gamma probe/radioactivity guided SLNB had 28.6% (4 of 14). When comparing operation time between attending and resident surgeon, time to identification of first SLN was not significantly different for fluorescence guided surgery (82 vs. 107 s, respectively) or with gamma probe (158 vs. 204 s); however, median times using the gamma probe were nearly double for both operators. We additionally show the durability of fluorescence signal up to 5 days and clear visualization of proposed tracer with commercially available intraoperative imagers. Conclusion The use of fluorescent labeled tilmanocept decreases operative time needed for SLNB as well as reduces the amount of nonsentinel tissue removed. Level of Evidence N/A.