Visualization of endometriosis with laparoscopy and near‐infrared optics with indocyanine green

Abstract

Introduction:Endometriosis is a common health problem, affecting 10% of women of reproductive age. Laparoscopic surgery is proven to relieve pain and to improve fertility in women with endometriosis. However, identifying peritoneal endometriosis lesions may be difficult due to their polymorphic aspects. Endometriosis lesions harbor a high degree of neovascularization. The visualization of tissue perfusion by the additional use of near infrared fluorescence imaging with indocyanine green (ICG) may improve the detection of endometriosis lesions. Material and methods:In a single-center, prospective, single-arm pilot study, patients undergoing laparoscopic surgery for suspected endometriosis and/or infertility were recruited. All patients first had white light imaging with systematical documentation of all suspicious areas. ICG was then administered intravenously at .3 mg/kg bodyweight and the near infrared imaging was activated and an identical documentation of suspected lesions was performed again. After removal, the specimen were sent to pathology. Clinical trial registration: clinicaltrials.gov NCT03850158. Results:In total, 173 suspected lesions were identified and excised, of which 150 had histologically proven endometriosis. Of the total number, 166 suspected lesions were detected using white-light and 32 with ICG. Among the 32 suspected lesions found with ICG, 22 were confirmed to be endometriosis. Seven additional lesions were identified with ICG alone, of which only one was histologically proven endometriosis. Positive predictive values were 89.8%, 68.8% and 86.7% for white-light laparoscopy alone, near-infrared (NIR)-ICG visualization alone, and the combination of white-light and NIR-ICG, respectively. ICG exposure time, previous abdominal surgery and rARSM stage showed a statistically significant impact on the ICG detection rate. In seven patients, ICG was used for the resection of deep infiltrating nodules from the rectum. In these cases, NIR fluorescence imaging with ICG was useful to define the borders between an endometriotic nodule and healthy tissue. Conclusions: The diagnostic value of NIR-ICG imaging in identifying endometriosis appears to be minimal. ICG exposure time over 20 minutes, no previous abdominal Preoperative symptoms, n (%) Pain 45 (71.4) Infertility 4 (6.3) Both 13 (20.6) Prior surgery for endometriosis, n (%) 34 (54.0) Previous abdominal surgery, n (%) 40 (63.5) Preoperative hormonal treatment, n (%) 38 (60.3) Abbreviations: n, number of patients; SD, standard deviation; rASRM, revised American Society for Reproductive Medicine.

Indocyanine green in the surgical management of endometriosis: A systematic review

“…Conversely, Siegenthaler et al 8 and Lier et al 15 showed no advantage for NIR fluorescence imaging with ICG. Indeed, in their pilot study of 63 patients, Siegenthaler et al 8 reported a sensitivity of NIR‐ICG of 14.7%, very different from that found by Cosentino 11 and Vizzielli, 12 whose sensitivity was 82%. This inhomogeneity is difficult to interpret: in the two papers, the substantial differences concern the percentage of patients with previous surgery for endometriosis, 54% for Siegenthaler 8 and 44% in Cosentino’s work 11 and the fluorescence display time, which varies for the Siegenthaler between 2 and 20 minutes and for Cosenti between 5 and 30 minutes.…”

“…Moreover, only seven additional lesions were identified with ICG, of which only one was pathologically proven to be endometriosis. About the secondary outcome, the ICG detection rate was positively affected by the exposure time over 20 minutes, with no previous abdominal surgery and with a low rASRM 8 …”

“…These 17 studies included six video‐articles (8 patients), 19‐22,26,27 one case report (1 patient), 16 one case series (6 patients), 14 two retrospective observational studies (57 patients), 12,24 seven prospective longitudinal studies, 8,11,13,15,18,23,25 one of which randomized 15 within‐subject (196 patients). When insufficient information was reported in the available papers, if necessary, we consulted the authors for further completing data; any disagreement was discussed and resolved by consensus.…”

“…Although the neoangiogenesis and increased blood vessel density typical of DIE 39,40 present a rationale for the use of NIR‐ICG technology, there are elements to consider that can influence the success of this method and that may explain the difference in sensitivity reported by various authors 8,11,12,15 . Previous retroperitoneal surgery, fibrosis and the reduction of neoangiogenesis related to the use of estrogen‐progestin or gonadotropin‐releasing hormone agonist, may be responsible for an altered microcirculation at the level of peritoneal lesions or DIE nodules 8 . The variability among the various authors, regarding the times reported between the administration of ICG and the visualization of the fluorescence, should also be considered, with times for viewing varying from a few seconds to 30 minutes 8,11,12,15,16,23,25‐27 …”

“…Although the medical therapy represents the benchmark for endometriosis, the surgical option has proven to be effective, safe and tolerable where there is serious constipation and intestinal cramping, painful bowel movements, dyschezia, prolonged diarrhea with rectal tenesmus, rectal bleeding and, in severe cases, intestinal stenosis or occlusion 6 . DIE treatment needs high surgical skill and wide experience to achieve the radicality and to preserve, as much as possible, the vascularization and the neurovegetative function of the pelvic organs 7‐9 …”