ICG for Visualization of the Ureters in DIE

Endometriosis is a common condition with an incidence of approximately 10% of all women in the fertile phase. Deep infiltrating endometriosis (DIE) has been shown to be associated with high morbidity. A retrospective study of 700 patients has shown lower urinary tract involvement in up to 52.6% of cases with DIE. In most studies, the bladder is cited as the most common site of DIE in the urinary tract, with the ureter being the second most common lesion site. In cases of ureteral endometriosis, a procedure called ureterolysis is essential because complete resection of the endometriosis is necessary to resolve or prevent renal obstruction. In addition, ureterolysis is obligatory in the context of dissection of endometriosis involving the rectovaginal septum, sacrouterine ligaments, or rectum. Ureterolysis is the process of freeing the ureter from both endometriotic nodules as a therapeutic procedure and from physiologic surrounding tissue and structures for complete visualization. Because ureterolysis is a high-risk procedure for ureteral lesions, alternatives are desirable. ICG is a fluorescent dye that has been used for decades for various indications, including retinal angiography, determination of tissue viability, and testing of cardiac and liver function. It has gained an important role in intraoperative visualization of tissue perfusion as well as sentinel lymph nodes in tumor surgery. ICG has also been used and described for ureteral imageability. However, these studies included small populations of 10-30 patients. None of the aforementioned studies have investigated the imageability of the ureters in endometriosis and with regard to a possible reduction in the need for ureteral dissection. The investigators perform a cystoscopy with a retrograde injection of ICG in both ureters. ICG and thus the ureters are visualized during laparoscopy by near-infrared light contained in our camera systems. The additional use of fluorescence imaging of the ureters with ICG injected into the ureters during laparoscopic resection of deep infiltrating endometriosis is intended to improve visualization of the ureters and thus may prevent complete ureterolysis, which is considered a high-risk procedure. It is a safe procedure as ICG has been shown to have an excellent safety profile. The aim of the study is to prove the feasibility of ureteral visualization using intraureteral ICG in 2D laparoscopy for women with deep infiltrating endometriosis by means of near-infrared fluorescence imaging of the ureters. In our secondary endpoints the investigators want to describe the duration time of ICG injection, the duration until visualization of the ureters, the detection rate of fluorescing ureters after ICG-injection, the duration until maximum fluorescence is achieved, the duration until the ureters can no longer be displayed, the length of performed ureterolysis in centimeters and the safety of intraureteral ICG injection.

Inclusion Criteria: * Informed Consent as documented by signature * Age 18 or older * Premenopausal status (menopause is defined as amenorrhea lasting one year or longer) * Proven (by laparoscopy or MRI) or highly suspected (ultrasound or clinically) deep infiltrating endometriosis Exclusion Criteria: * No DIE detectable intraoperatively * Known or suspected allergy to iodine, shellfish, or ICG dye * Hyperthyroid metabolic state (excluding treated hyperthyroidism with euthyroid metabolic state) * Severe renal insufficiency (GFR \< 30ml/min) * Simultaneous therapy with beta-blockers * Pregnant (positive human chorionic gonadotropin in the blood) or breastfeeding women * Intention to become pregnant during the course of the study * Inability to follow the procedures of the study (due to language problems, psychological disorders, dementia) * Previous history of radiation therapy of the pelvis * Presence of medical conditions contraindicating general anesthesia or standard laparoscopic surgery * Active, non treated urinary tract infection * Active pyelonephritis * Women having undergone surgery for reimplantation of the ureters (UCNS) or nephrostomy