Giuseppe Quero, MD1, Alfonso Lapergola, MD2, Vincent Agnus, PhD2, Paola Saccomandi, PhD1, Ludovica Guerriero, MD1, Didier Mutter, MD, PhD, FACS2, Jacques Marescaux, MD, FACS, HonFRCS, HonFJSES2, Michele Diana, MD2. 1IHU-Strasbourg, Institute of Image-Guided Surgery, Strasbourg, France, 2IRCAD, Research Institute against Cancer of the Digestive System, Strasbourg, France
Background: The aim of this experimental study was to evaluate the ability of a software-based analysis of the fluorescence signal to identify the patterns of different forms of bowel ischemia.
Methods: Twelve pigs were included. Through a minimally-invasive approach, the sigmoid was exposed and the inferior mesenteric artery (IMA; group A: n=4) or the vein (IMV; group V: n=4) or both (group A-V: n=4) were clipped using two clips on each vessel, 5 cm apart. The sigmoid was divided in 3 areas: P= proximal to the first clip; C= central, between the two clips; D= distal to the second clip. Indocyanine Green (ICG) was injected intravenously (0.2mg/Kg). The Near-Infrared optimized laparoscope (D-Light P, Karl Storz), was switched to near-infrared mode to capture the fluorescence signal. The time-to-peak (seconds) and the maximum fluorescence intensity were recorded within the first 60 seconds after the injection, using ad hoc software (ER PERFUSION). A normalized fluorescence intensity unit (NFIU: 0-to-1) was attributed, pixel-by-pixel as a ratio of the maximal. The over-time variation of the NFIU was evaluated every 10 minutes during 50 minutes, using the same software. Capillary lactates were sampled after puncturing the sigmoid serosa at the 3 zones.
Results: In the group A, the time-to-peak was significantly shorter (8.9±4.1) at the P area vs. C (25.8±11.8; p=0.005) and D (23.04±16; p=0.03). Similarly, in the group A-V, time-to-peak was shorter at the P side (6.7±2.4) vs. C (17.4±7.52; p=0.02) and D (23±10.46; p=0.02). In the group V, the time-to-peak was significantly shorter at the P (7.6±2.7) vs. D (9.04±3.13; p=0.02). Among the groups, there was no difference of time-to-peak at the P side. At the C, it was longer in the group A (25.8±11.8) when compared to the group V (9.14±3.85; p=0.01) and A-V (17.4±7.32; p=0.02). The evolution of the signal, was significantly different among the groups at the various areas. A clinically relevant finding was that in the group A and AV, the fluorescence intensity in the C area, remains stable after the first 10 minutes (p=0.13 and 0.32 respectively), when compared to the maximal, while it decreases significantly in the group V (p=0.006).
Conclusions: The computer-assisted dynamic analysis of the fluorescence signal enables the discrimination between different bowel ischemia models. A machine-learning approach is ongoing to improve the software and enable the conversion of the identified patterns into real-time images.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 87640
Program Number: S054
Presentation Session: Instrumentation / Devices / Technologies Session
Presentation Type: Podium