Near infrared fluorescence imaging system for laparoscopic partial nephrectomy

Recently, the use of indocyanine green (ICG) with near infrared fluorescence (NIRF) imaging has emerged as an alternative technique for the real-time delineation of resection margins during partial nephrectomy (PN). We aimed to assess the feasibility of using NIRF imaging with ICG during laparoscopic partial nephrectomy (LPN) to delineate the margin between normal renal parenchyma and renal cortical tumors.

A retrospective comparison of real-time tumor margin identification and operative outcomes was conducted for 83 patients who underwent LPN with NIRF imaging (IMAGE1 system) and 74 patients who did not.

Tumor margins were identified in 82% of cases in the NIRF group, with a rate of 79% for the clear cell renal carcinoma cases only. Volume of blood loss was higher for the NIRF than normal imaging group (p = 0.015), while the warm ischemia time was significantly shorter (p < 0.01) for the NIRF group. There was no significant difference in the pre to postoperative change in estimated glomerular filtration rate (p = 0.38) or rate of severe complications (Clavien grade ≥ 3; p = 0.88). The rate of positive surgical margins was comparable between the groups (3%; p = 0.91).

NIRF imaging with ICG during LPN was safe and feasible, although the surgical outcomes with NIRF alone was not significantly superior to the ones with conventional methods.