Prospective Evaluation of Near-infrared Fluorescence Imaging Use as a Supportive Tool in Deep Infiltrating Endometriosis Surgery

Overview

The aim of the study is to establish a new and more accurate method to visualize the peritoneal changes caused by endometriosis using Indocyanine Green mediated fluorescence imaging. The hypothesis is that Indocyanine Green, a fluorescent dye that has wide applications throughout medicine in identifying vascularity of tissues and neo-vascularization, could facilitate the localization and excision of endometriotic lesions exploiting the hypervascularization due to the chronic inflammation. The already published Pilot Study GRE-ENDO (Cosentino F, Near-Infrared Imaging with Indocyanine Green for Detection of Endometriosis Lesions (Gre-Endo Trial): A Pilot Study.), encouraged the effort of a larger prospective trial. Based on the mini-max two-stage design by Simon \[Simon R. Optimal two stage design for phase II clinical trials\], the investigators tested the null hypothesis that the true rate of pathologically assessed endometriosis would improve from 87% to the clinically relevant alternative of 100.0%, as assessed by NIR-ICG laparoscopy.

Patients were recruited within the clinical routine after indication for laparoscopy under consideration of the inclusion and exclusion criteria. The sample size was calculated according to the study design by Simon (Simon R. Optimal two stage design for phase II clinical trials), using an α-error of 0.01 (two-sided) and a β-error of 0.90. Considering a patient dropout of approximately 10%, the study was planned to enrol at least 47 women. The first abdominal and pelvi's inspection was made using direct laparoscope visualization under white light conditions. All areas suspected of peritoneal endometriosis was classified as white, black and red lesions and recorded together with their anatomic location in the surgical record for the purposes of subsequent extirpation. After the first visual inspection the patient was administered with 0.05 - 0.25 mg /(kg BW) Indocyanine Green intravenously. The Indocyanine Green imaging mode of the Olympus Indocyanine Green Imaging System was activated and suspected areas in Indocyanine Green imaging mode were recorded with them corresponding appearance in white light mode. If suspected areas were visible either in white light or Indocyanine Green imaging mode, specific sample has been taken from these areas. In addition, control biopsy specimens from inconspicuous peritoneum has been taken.