Comparison of enhanced laparoscopic imaging techniques in endometriosis surgery: a diagnostic accuracy study

The Role of Indocyanine Green With Near-Infrared Imaging for the Intraoperative Detection and Enhancement of Endometriosis Lesions: A Narrative Review

Background: There is a clinical need for improved intraoperative detection of endometriosis, and the use of Indocyanine Green with Near-Infrared Imaging (NIR-ICG) is a novel technique for this purpose. The aim of this review is to determine whether NIR-ICG is an effective tool for endometriosis detection and establish an evidence-based methodology for its use.Methods: This review searches Ovid MEDLINE and Embase through July 2023 and considers primary literature published in English describing the use of NIR-ICG to detect endometriosis intraoperatively. Case studies, video demonstrations and articles describing NIR-ICG used for other surgical roles were not considered. Identified studies were screened independently by two authors, and data was extracted by a single author.Results: NIR-ICG was found to enhance the detection of endometriosis in six out of the nine included studies with additional lesion identification, and to have an unchanged or reduced efficacy compared to current standards in the remaining three. Across all studies there were lesions missed by NIR-ICG which were detected by conventional imaging. A greater duration of time between dye administration and visualisation of lesions was found to be more effective for detection. The ideal ICG protocol proposed from this review is a fixed amount of dye proportional to patient weight prior to surgery (0.25-0.3 mg/kg) followed by a longer waiting time before imaging (10-30 min).Conclusion: NIR-ICG has a possible role to enhance the identification of endometriosis intraoperatively as an adjunct to conventional white light imaging, particularly deeper infiltrating disease. However, substantial further research is required in this field.

Targeted Imaging of Endometriosis and Image-Guided Resection of Lesions Using Gonadotropin-Releasing Hormone Analogue-Modified Indocyanine Green

Objective

In this study, we utilized gonadotropin-releasing hormone analogue-modified indocyanine green (GnRHa-ICG) to improve the accuracy of intraoperative recognition and resection of endometriotic lesions.

Methods

Gonadotropin-releasing hormone receptor (GnRHR) expression was detected in endometriosis tissues and cell lines via immunohistochemistry and western blotting. The in vitro binding capacities of GnRHa, GnRHa-ICG, and ICG were determined using fluorescence microscopy and flow cytometry. In vivo imaging was performed in mouse models of endometriosis using a near-infrared fluorescence (NIRF) imaging system and fluorescence navigation system. The ex vivo binding capacity was determined using confocal fluorescence microscopy.

Results

GnRHa-ICG exhibited a significantly stronger binding capacity to endometriotic cells and tissues than ICG. In mice with endometriosis, GnRHa-ICG specifically imaged endometriotic tissues (EMTs) after intraperitoneal administration, whereas ICG exhibited signals in the intestine. GnRHa-ICG showed the highest fluorescence signals in the EMTs at 2 h and a good signal-to-noise ratio at 48 h postadministration. Compared with traditional surgery under white light, targeted NIRF imaging-guided surgery completely resected endometriotic lesions with a sensitivity of 97.3% and specificity of 77.8%. No obvious toxicity was observed in routine blood tests, serum biochemicals, or histopathology in mice.

Conclusions

GnRHa-ICG specifically recognized and localized endometriotic lesions and guided complete resection of lesions with high accuracy.

Surgical polarimetric endoscopy for the detection of laryngeal cancer

The standard-of-care for the detection of laryngeal pathologies involves distinguishing suspicious lesions from surrounding healthy tissue via contrasts in colour and texture captured by white-light endoscopy. However, the technique is insufficiently sensitive and thus leads to unsatisfactory rates of false negatives. Here we show that laryngeal lesions can be better detected in real time by taking advantage of differences in the light-polarization properties of cancer and healthy tissues. By measuring differences in polarized-light retardance and depolarization, the technique, which we named 'surgical polarimetric endoscopy' (SPE), generates about one-order-of-magnitude greater contrast than white-light endoscopy, and hence allows for the better discrimination of cancerous lesions, as we show with patients diagnosed with squamous cell carcinoma. Polarimetric imaging of excised and stained slices of laryngeal tissue indicated that changes in the retardance of polarized light can be largely attributed to architectural features of the tissue. We also assessed SPE to aid routine transoral laser surgery for the removal of a cancerous lesion, indicating that SPE can complement white-light endoscopy for the detection of laryngeal cancer.

Early stage gastric adenocarcinoma: clinical and molecular landscapes

Gastric adenocarcinoma, even when diagnosed at an early (localized) disease stage, poses a major health-care burden with cure rates that remain unsatisfactorily low, particularly in Western countries. This lack of progress reflects, among other aspects, the impracticality of early diagnosis, considerable variations in therapeutic approaches that is partly based on regional preferences, and the ingrained heterogeneity of gastric adenocarcinoma cells and their associated tumour microenvironment (TME). Clinical trials have long applied empirical interventions with the assumption that all early stage gastric adenocarcinomas are alike. Despite certain successes, the shortcomings of these approaches can potentially be overcome by targeting the specific molecular subsets of gastric adenocarcinomas identified by genomic and/or multi-omics analyses, including microsatellite instability-high, Epstein-Barr virus-induced, DNA damage repair-deficient, HER2-positive and PD-L1-high subtypes. Future approaches, including the availability of sophisticated vaccines, novel antibody technologies, agents targeting TME components (including fibroblasts, macrophages, cytokines or chemokines, and T cells) and novel immune checkpoint inhibitors, supported by improved tissue-based and blood-based diagnostic assays, seem promising. In this Review, we highlight current knowledge of the molecular and cellular biology of gastric adenocarcinomas, summarize the current approaches to clinical management of the disease, and consider the role of novel management and/or treatment strategies.

European Association for Endoscopic Surgery (EAES) consensus on Indocyanine Green (ICG) fluorescence-guided surgery

BACKGROUND

In recent years, the use of Indocyanine Green (ICG) fluorescence-guided surgery during open and laparoscopic procedures has exponentially expanded across various clinical settings. The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on this topic with the aim of creating evidence-based statements and recommendations for the surgical community.

METHODS

An expert panel of surgeons has been selected and invited to participate to this project. Systematic reviews of the PubMed, Embase and Cochrane libraries were performed to identify evidence on potential benefits of ICG fluorescence-guided surgery on clinical practice and patient outcomes. Statements and recommendations were prepared and unanimously agreed by the panel; they were then submitted to all EAES members through a two-rounds online survey and results presented at the EAES annual congress, Barcelona, November 2021.

RESULTS

A total of 18,273 abstracts were screened with 117 articles included. 22 statements and 16 recommendations were generated and approved. In some areas, such as the use of ICG fluorescence-guided surgery during laparoscopic cholecystectomy, the perfusion assessment in colorectal surgery and the search for the sentinel lymph nodes in gynaecological malignancies, the large number of evidences in literature has allowed us to strongly recommend the use of ICG for a better anatomical definition and a reduction in post-operative complications.

CONCLUSIONS

Overall, from the systematic literature review performed by the experts panel and the survey extended to all EAES members, ICG fluorescence-guided surgery could be considered a safe and effective technology. Future robust clinical research is required to specifically validate multiple organ-specific applications and the potential benefits of this technique on clinical outcomes.

Intraoperative dyes, fluorescence and enhanced imaging in benign gynaecologic surgery

PURPOSE OF REVIEW

We review the literature regarding the use of dyes and fluorescence-guided visualization techniques in gynaecological surgery. We also discuss advances in imaging that may enhance surgery by incorporating real-time visual feedback through augmented reality and preoperative planning with patient-specific, three-dimensional printed surgical fields.

RECENT FINDINGS

Methylene blue is one of the most commonly used dyes, while indocyanine green is the most used agent in fluorescence-guided surgery. Augmented reality and three-dimensional printing are also being increasingly used in gynaecology.

SUMMARY

Dyes and fluorescence-based surgeries are commonly utilized to improve anatomic identification, preservation of healthy tissue and excision of disease. In addition, we explore how augmented reality and three-dimensional printing are used in gynaecology.

The Use of near Infra-Red Radiation Imaging after Injection of Indocyanine Green (NIR-ICG) during Laparoscopic Treatment of Benign Gynecologic Conditions: Towards Minimalized Surgery. A Systematic Review of Literature

Background and Objectives: To assess the use of near infrared radiation imaging after injection of indocyanine green (NIR-ICG) during laparoscopic treatment of benign gynecologic conditions. Materials and Methods: A systematic review of the literature was performed searching 7 electronic databases from their inception to March 2022 for all studies which assessed the use of NIR-ICG during laparoscopic treatment of benign gynecological conditions. Results: 16 studies (1 randomized within subject clinical trial and 15 observational studies) with 416 women were included. Thirteen studies assessed patients with endometriosis, and 3 studies assessed non-endometriosis patients. In endometriosis patients, NIR-ICG use appeared to be a safe tool for improving the visualization of endometriotic lesions and ureters, the surgical decision-making process with the assessment of ureteral perfusion after conservative surgery and the intraoperative assessment of bowel perfusion during recto-sigmoid endometriosis nodule surgery. In non-endometriosis patients, NIR-ICG use appeared to be a safe tool for evaluating vascular perfusion of the vaginal cuff during total laparoscopic hysterectomy (TLH) and robotic-assisted total laparoscopic hysterectomy (RATLH), and intraoperative assessment of ovarian perfusion in adnexal torsion. Conclusions: NIR-ICG appeared to be a useful tool for enhancing laparoscopic treatment of some benign gynecologic conditions and for moving from minimally invasive surgery to minimalized surgery. In particular, it might improve treatment of endometriosis (with particular regard to deep infiltrating endometriosis), benign diseases requiring TLH and RATLH and adnexal torsion. However, although preliminary findings appear promising, further investigation with well-designed larger studies is needed.

Near-Infrared Fluorescence Imaging for the Intraoperative Detection of Endometriosis: A Pilot Study

Introduction: Endometriosis surgery is associated with a high risk of reoperation due to an insufficient recognition of endometriotic lesions. Our aim was to explore the role of near-infrared fluorescence (NIRF) imaging for the visualization and identification of endometriotic lesions next to conventional white light (WL) laparoscopy. Materials and methods: Fifteen women scheduled for diagnostic laparoscopy in whom peritoneal endometriosis was suspected were included. Peritoneal exploration was performed in WL, followed by NIRF imaging after ICG administration. Biopsies of all the suspected lesions were taken for histological examination. Subjective evaluations of the equipment and NIRF imaging were also performed. Results: Only 61% (44) of the biopsied lesions contained endometriosis. The positive predictive value (PPV) for the lesions found in WL was 64%. The PPV for the lesions found under NIRF was 69% and the PPV for the lesions found in both modes was 61%. The mean satisfaction of surgeons regarding the surgical procedure and equipment using both imaging modalities was 6.5 (p > 0.05) on a 10 item Likert scale and the mean satisfaction with the quality of the NIRF imaging was 7.4 (p > 0.05). Conclusion: In this study, the additional value of NIRF imaging, although feasible, was found to be limited for the intraoperative detection of endometriotic lesions.

Improving tissue characterization, differentiation and diagnosis in gynecology with the narrow-band imaging technique: A systematic review

Narrow-band imaging (NBI), an on-demand, real-time endoscopic imaging technique, was developed to enhance visualization of the mucosal vascular network and surface texture. The present article provides a systematic review of studies that assessed the use of NBI in gynecological endoscopy. The following electronic databases were searched: PubMed (1950-2020), Google Scholar (2004-2020) and Cochrane Library (2010-2020). In the initial search, 3,836 entries were identified, of which 31 were finally included in the systematic review. Of the selected studies, 10 (32%) were case reports, 19 (61.2%) were prospective studies and 2 (6.4%) were randomized controlled trials with control groups. The selected studies reported on the use of NBI in hysteroscopy, laparoscopy and colposcopy. It was revealed that NBI utilization in hysteroscopy increased the accuracy, sensitivity and specificity in detecting malignant and premalignant lesions. NBI improved the specificity and sensitivity in the detection of endometriotic lesions and cervical lesions. Conventional white light endoscopy in gynecology may be significantly improved by the use of NBI. Further studies with larger cohorts and improved design are required to achieve more reliable results. It is of special interest that utilization of this method requires apparatus which is expensive; concerns are the long training and experience of staff required and the long learning curve.

Comprehensive Review of Fluorescence Applications in Gynecology

Since the introduction of indocyanine green (ICG) as a fluorophore in near-infrared imaging, fluorescence visualization has become an essential tool in many fields of surgery. In the field of gynecology, recent new applications have been proposed and found their place in clinical practice. Different applications in gynecology were investigated, subcategorized, and overviewed concerning surgical applications and available dyes. Specific applications in which fluorescence-guided surgery was implemented in gynecology are described in this manuscript—namely, sentinel node biopsy, mesometrium visualization, angiography of different organs, safety issues in pregnant women, ureters visualization, detection of peritoneal metastases, targeted fluorophores for cancer detection, fluorescent contamination hysterectomy, lymphography for lower limb lymphedema prevention, tumor margin detection, endometriosis, and metastases mapping. With evolving technology, further innovative research on the new applications of fluorescence visualization in cancer surgery may help to establish these techniques as standards of high-quality surgery in gynecology. However, more investigations are necessary in order to assess if these innovative tools can also be effective to improve patient outcomes and quality of life in different gynecologic malignancies.

Clinical use of indocyanine green during nerve-sparing surgery for deep endometriosis

OBJECTIVE

To describe the anatomic and technical highlights of a novel nerve-sparing surgery in deep endometriosis (DE) using near-infrared (NIR) fluorescence technology and indocyanine green (ICG).

DESIGN

Stepwise demonstration of this method with narrated video footage.

SETTING

An urban general hospital.

PATIENT(S)

A 48-year-old woman was referred for severe chronic pelvic pain, dysmenorrhea, and pain on defecation, all of which were resistant to medication therapy. Magnetic resonance imaging revealed uterine adenomyosis and left ovarian endometrioma with DE involving the uterosacral ligament, posterior cervix, and surface of the rectum, with complete cul-de-sac obliteration.

INTERVENTION(S)

An intravenous injection of 0.25 mg/kg body weight of ICG for intraoperative NIR fluorescence imaging. Ethics approval was obtained from the institutional review board at our hospital (IRB No.: 985).

MAIN OUTCOME MEASURE(S)

Evaluation of blood perfusion of DE nodule and achieving better visualization of anatomic relationship to the pelvic autonomic nerves.

RESULT(S)

The procedure was performed using the following eight steps with the da Vinci Xi surgical platform: Step 0, observing peritoneal endometriotic lesions; Step 1, adhesiolysis and adnexal surgery; Step 2, separation of the nerve plane; Step 3, dissection of the ureter; Step 4, reopening of the pouch of Douglas; Step 5, complete removal of DE lesions while avoiding injury to the nerve plane; Step 6, hysterectomy (if the patient desires nonfertility-sparing surgery); Step 7, checking for rectal injury using air leakage test and tissue perfusion; and Step 8, barrier agents for adhesion prevention. During surgery, we could easily identify ischemic nodules, which included DE and fibrosis under NIR fluorescence imaging, beyond the limits of macroscopic disease. Endometriosis or fibrosis was confirmed pathologically from all resected tissues, and resection margins of these tissues were negative for the disease. These results suggest that this technique might be feasible for objectively identifying the border between DE lesions and healthy tissue. Furthermore, the hypogastric nerve and inferior hypogastric plexus were strongly highlighted by ICG and objectively preserved with the assessment of perfusion. The patient developed no perioperative complications, including postoperative bladder or rectal dysfunction after surgery.

CONCLUSION(S)

To our knowledge, this is the first reported use of ICG during nerve-sparing surgery for gynecologic disease. Application of ICG with NIR fluorescence appears potentially useful, not only to remove DE, but also to improve nerve-sparing.

Surgical management of endometriotic women with pregnancy intention in France: A national snapshot of centers performing a high volume of endometriosis procedures

OBJECTIVE

To provide a snapshot of the surgical management of endometriosis in French high-volume activity centers.

METHODS

Analysis of prospectively collected data between November 2015 and May 2017 in 21 centers with a high volume of endometriosis surgery in France. Each facility could include up to 40 patients undergoing laparoscopy for endometriosis. Data were collected before and two months after surgery.

RESULTS

361 patients were enrolled in the study. Twenty-seven patients (7.48%) were lost to follow-up at the month 2 visit. Endometriosis stage was I-II in 33.70% of patients and III-IV in 66.30%. Uterosacral ligament resection was the most frequently performed procedure (50.97%) followed by rectal surgery (31.58%), ovarian procedures for endometrioma, procedures for ureters (21.33%) and the bladder (11.91%). Antiadhesion agents were employed in 215/361 (59.56%) patients. The median length of hospital stay after surgery was 2 (IQR 1 - 4) days. Post-operative complications were recorded in 9.34% of patients. Rectovaginal fistulae occurred in 8 patients (2.41%), pelvic abscess in 4 (1.20%) and bladder atony in 3 (0.90%). 17 patients (5.14%) required a second surgical procedure after a median time of 31 days (IQR 9 - 81). Two months after surgery, 95.09% of patients reported being satisfied or very satisfied with the surgery.

CONCLUSION

Our study shows that surgical management of endometriosis in centers with a high volume of endometriosis surgery, mainly concerns women presenting with severe disease and deep localizations, with an overall risk of major complications inferior to 10% and a high rate of patient satisfaction.

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

INTRODUCTION

Endometriosis is a very common disease that affects up to 10% of the female population. The use of indocyanine green (ICG) dye has been proposed to allow the proper localization of endometriotic lesions during surgery. Our purpose is to offer an overview of near-infrared (NIR)-ICG in the surgical treatment of superficial peritoneal endometriosis and deep infiltrating endometriosis.

MATERIAL AND METHODS

Electronic databases were searched, including MEDLINE, Embase, Web of Science, Scopus, ClinicalTrial.gov, OVID and Cochrane Library. The studies were identified with the use of a mesh combination of the following keywords: "indocyanine green", "endometriosis", "deep endometriosis", "robotic surgery", "laparoscopy", "ureter", "rectosigmoid" from 2000 to May 2020. All articles describing the use of ICG applied to endometriosis surgery were considered for review. Only original papers that reported specific experience data on the topic were included. Moreover, video-articles were included in the analysis. Quality and risk of bias were evaluated by two authors, respectively.

RESULTS

Fifty-three studies were reviewed and reviews or comment articles not reporting original data and original articles lacking specific data on the application of ICG in patients affected by endometriosis were excluded. The quality of the 17 studies included was assessed. Eight studies suggested the usefulness of NIR-ICG as a tool in the detection of endometriosis during surgery, and one randomized controlled trial and one prospective study did not confirm the advantage of its use. Eight studies found that NIR-ICG was useful for the evaluation of vascularization in intestinal anastomoses and ureterolysis after surgery for deep infiltrating endometriosis.

CONCLUSIONS

NIR-ICG appears useful in the evaluation of vascularization in intestinal anastomoses after segmental resection, confirming its role even after ureterolysis for parametrial deep infiltrating endometriosis. However, its usefulness as a tool in the detection of endometriosis during surgery is inconsistent.