Quantification of indocyanine green near-infrared fluorescence bowel perfusion assessment in colorectal surgery

Abstract

Background Indocyanine green near-infrared fluorescence bowel perfusion assessment has shown its potential benefit in preventing anastomotic leakage. However, the surgeon's subjective visual interpretation of the fluorescence signal limits the validity and reproducibility of the technique. Therefore, this study aimed to identify objective quantified bowel perfusion patterns in patients undergoing colorectal surgery using a standardized imaging protocol. Method A standardized fluorescence video was recorded. Postoperatively, the fluorescence videos were quantified by drawing contiguous region of interests (ROIs) on the bowel. For each ROI, a time-intensity curve was plotted from which perfusion parameters (n = 10) were derived and analyzed. Furthermore, the inter-observer agreement of the surgeon’s subjective interpretation of the fluorescence signal was assessed. Results Twenty patients who underwent colorectal surgery were included in the study. Based on the quantified time-intensity curves, three different perfusion patterns were identified. Similar for both the ileum and colon, perfusion pattern 1 had a steep inflow that reached its peak fluorescence intensity rapidly, followed by a steep outflow. Perfusion pattern 2 had a relatively flat outflow slope immediately followed by its plateau phase. Perfusion pattern 3 only reached its peak fluorescence intensity after 3 min with a slow inflow gradient preceding it. The inter-observer agreement was poor-moderate (Intraclass Correlation Coefficient (ICC): 0.378, 95% CI 0.210–0.579). Conclusion This study showed that quantification of bowel perfusion is a feasible method to differentiate between different perfusion patterns. In addition, the poor-moderate inter-observer agreement of the subjective interpretation of the fluorescence signal between surgeons emphasizes the need for objective quantification.

Quantitative analysis of intestinal perfusion with indocyanine green (ICG) and methylene blue (MB) using a single clinically approved fluorescence imaging system: a demonstration in a porcine model

“…Previous studies were conducted to establish and gather validity evidence for a method of quantifying fluorescence angiography [ 20 – 24 ]. This revealed that bowel perfusion quantification is a feasible method to differentiate between different perfusion patterns, highlighting the possibility of using standardized imaging protocols [ 21 ]. According to a recent consensus paper on ICG fluorescence angiography, we concur with the authors’ standpoint that additional investigation into quantitatively evaluating fluorescence is imperative.…”

“…According to a recent consensus paper on ICG fluorescence angiography, we concur with the authors’ standpoint that additional investigation into quantitatively evaluating fluorescence is imperative. This will help to reduce the subjective variability associated with perfusion assessment [ 21 ], and make it easier to compare study outcomes with different dyes, and will improve the validity and reproducibility of such data in daily practice.…”

The Safe Values of Quantitative Perfusion Parameters of ICG Angiography Based on Tissue Oxygenation of Hyperspectral Imaging for Laparoscopic Colorectal Surgery: A Prospective Observational Study

“…This highlights the potential importance of evaluating blood flow during colorectal surgery to decrease complications [31]. Therefore, it is expected that perfusion assessment should become an essential surgical procedure for ensuring patient safety in colorectal surgery [32].…”