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 I