Usefulness of fluorescence imaging and real-time tissue elastography to overcome pitfalls of laparoscopic liver resection

Objective: Magnified view is one of advantages during laparoscopic liver resection (LLR). However, LLR lacks global hepatic overview and tactile feedback. We, herein, demonstrate usefulness of fluorescence imaging and real-time tissue elastography (RTE) during LLR to overcome pitfalls of magnified view and lack of tactile feedback.Method: (1) Visualization of liver tumor and bile duct were evaluated in 6 patients (13 lesions) and 24 patients, respectively, using laparoscopic fluorescence system (Olympus Medical Systems). (2) Tumor visualization ability and virtual tactile sensibility of RTE (Hitachi-Aloka Medical) were evaluated for 17 lesions in 14 patients. Elasticity images were scaled by colors: red, blue, and green for softest, hardest, and average strain components, respectively. Results: (1) Indocyanine green-fluorescence imaging visualized 61.5% of the tumors, including a chemotherpay-related vanishing tumor and post-ablation local recurrence which are hard to identify. It visualized bile duct for all 24 patients and guided hepatic vessel dissection which can be misidentified because of lacking hepatic overview. (2) RTE examination allowed visualization of all 17 lesions by depicting elasticity in different colors, while 6 lesions (35.3%) were iso-echoic and ill-defined in B-mode. RTE provided virtual tactile sensibility by visualizing heterogeneous tumor elasticity. Conclusion: Fluorescence imaging guided hepatic vessel identification, and RTE provides virtual tactile sensibility. These modalities are expected to complement pitfalls of magnified view and lack of tactile feedback during LLR.