Indocyanine Green Fluorescence Lymphography: A New Technique to Perform Lymphatic Sparing Laparoscopic Palomo Varicocelectomy in Children

Utilization of Indocyanine Green (ICG) Fluorescence in Patients with Pediatric Colorectal Diseases: The Current Applications and Reported Outcomes

In pediatric colorectal surgery, achieving and visualizing adequate perfusion during complex reconstructive procedures are paramount to ensure postoperative success. However, intraoperative identification of proper perfusion remains a challeng. This review synthesizes findings from the literature spanning from January 2010 to March 2024, sourced from Medline/PubMed, EMBASE, and other databases, to evaluate the role of indocyanine green (ICG) fluorescence imaging in enhancing surgical outcomes. Specifically, it explores the use of ICG in surgeries related to Hirschsprung disease, anorectal malformations, cloacal reconstructions, vaginal agenesis, bladder augmentation, and the construction of antegrade continence channels. Preliminary evidence suggests that ICG fluorescence significantly aids in intraoperative decision-making by improving the visualization of vascular networks and assessing tissue perfusion. Despite the limited number of studies, initial findings indicate that ICG may offer advantages over traditional clinical assessments for intestinal perfusion. Its application has demonstrated a promising safety profile in pediatric patients, underscoring the need for larger, prospective studies to validate these observations, quantify benefits, and further assess its impact on clinical outcomes. The potential of ICG to enhance pediatric colorectal surgery by providing real-time, accurate perfusion data could significantly improve surgical precision and patient recovery.

Robotic-assisted versus conventional laparoscopic ICG-fluorescence lymphatic-sparing palomo varicocelectomy: a comparative retrospective study of techniques and outcomes

PURPOSE

This study aimed to compare techniques and outcomes of robotic-assisted varicocelectomy (RAV) and laparoscopic varicocelectomy (LV).

METHODS

The medical records of 40 patients, who received RAV and LV over a 2-year period, were retrospectively analyzed. Palomo lymphatic-sparing varicocelectomy using ICG fluorescence was adopted in all cases. Three 5-mm trocars were placed in LV, whereas four ports, three 8-mm and one 5-mm, were placed in RAV. The spermatic vessels were ligated using clips in LV and ligatures in RAV. The two groups were compared regarding patient baseline and operative outcomes.

RESULTS

All patients, with median age of 14 years (range 11-17), had left grade 3 varicocele according to Dubin-Amelar. All were symptomatic and 33/40 (82.5%) presented left testicular hypotrophy. All procedures were completed without conversion. The average operative time was significantly shorter in LV [20 min (range 11-30)] than in RAV [34.5 min (range 30-46)] (p = 0.001). No significant differences regarding analgesic requirement and hospitalization were observed (p = 0.55). At long-term follow-up (30 months), no complications occurred in both groups. The cosmetic outcome was significantly better in LV than RAV at 6-month and 12-month evaluations (p = 0.001). The total cost was significantly lower in LV (1.587,07 €) compared to RAV (5.650,31 €) (p = 0.001).

CONCLUSION

RAV can be safely and effectively performed in pediatric patients, with the same excellent outcomes as conventional laparoscopic procedure. Laparoscopy has the advantages of faster surgery, smaller instruments, better cosmesis and lower cost than robotics. To date, laparoscopy remains preferable to robotics to treat pediatric varicocele.

Indocyanine green (ICG)-GUIDED lymphatic sparing laparoscopic varicocelectomy in children and adolescents. Is intratesticular injection of the dye safe? A mid-term follow-up study

BACKGROUND

Laparoscopic Palomo varicocelectomy using indocyanine green (ICG) fluorescent lymphography (FL) is standardized technique to perform lymphatic sparing and avoid post-operative hydrocele. No data regarding the safety of intratesticular injection of ICG are currently available.

OBJECTIVE

The study aimed to assess the safety and efficacy of this procedure at mid-term follow-up.

STUDY DESIGN

Seventy-two patients (median age 14.5 years) undergoing laparoscopic Palomo varicocelectomy using ICG-FL from January 2019 to July 2022, were enrolled. Operative indication was high-grade varicocele in all patients, associated symptoms in 30/72 (41.7 %) and left testicular hypotrophy in 42/72 (58.3 %). Follow-up included clinical examination at 1, 6, 12 months and scrotal Doppler ultrasonography (US) at 12 months postoperatively to assess varicocele persistence, hydrocele, and injections-related complications.

RESULTS

Lymphatic sparing was achieved using ICG-FL in all cases. No intra-operative complications or adverse reactions secondary to ICG occurred. The median follow-up was 22.8 months (range 11-49). Self-limited scrotal hematoma at the injection site occurred in 1/72 (1.4 %). Intratesticular hypoechoic millimetric area was detected at the injection site in 3/72 (4.2 %) on US. This finding disappeared after 1-year observation in 2/3 cases (66.7 %) (Figure). Persistent grade II varicocele was observed in 4/72 (5.5 %), not requiring re-intervention. No hydrocele occurred and 14/22 (63.6 %) with pre-operative hypotrophy showed catch-up growth.

DISCUSSION

ICG-FL was clinically safe, with no allergy or systemic adverse reactions to the dye reported in this series. No injury directly related to the injection of the dye was clinically observed, except for self-limiting scrotal hematoma in one patient. A millimetric hypoechoic and avascular area in the body of the left testicle at the injection site was found on scrotal US at 1-year follow-up in 3 patients of our series. This finding does not seem to be clinically relevant as patients were asymptomatic and serum tumor markers were normal in all cases. Furthermore, the hypoechoic area with calcifications resolved 1 year later in 2/3 patients. The absence of evolution of this finding seems to exclude the heteroplastic nature. We hypothesized that this finding may be linked to elevated volume and/or pressure of intratesticular injection. Future prospective study with larger series and longer follow-up is needed to assess long-term testicular outcomes.

CONCLUSION

Laparoscopic Palomo varicocelectomy using ICG-FL reported excellent outcomes with low incidence of varicocele persistence and no post-operative hydrocele. These preliminary data also confirmed safety of intratesticular injection of ICG at mid-term follow-up, without specific risks for both testis and patient.

Evaluating the Development Status of Fluorescence-Guided Surgery (FGS) in Pediatric Surgery Using the Idea, Development, Exploration, Assessment, and Long-Term Study (IDEAL) Framework

Fluorescence-guided surgery (FGS) is used in many pediatric subspecialties but there are currently no standard guidelines or outcome data. We aimed to assess the current status of FGS in pediatrics using the Idea, Development, Exploration, Assessment, and Long-term study (IDEAL) framework. Clinical papers on FGS in children published from January 2000 to December 2022 were systematically reviewed. The stage of research development was measured considering seven fields of application: biliary tree imaging, vascular perfusion for gastrointestinal procedures, lymphatic flow imaging, tumor resection, urogenital surgery, plastic surgery, and miscellaneous procedures. Fifty-nine articles were selected. For each field of application, the overall IDEAL stage was determined to be 2a for biliary tree imaging (10 publications, 102 cases), 1 for vascular perfusion for gastrointestinal procedures (8 publications, 28 cases), 1 for lymphatic flow imaging (12 publications, 33 cases), 2a for tumor resection (20 publications, 238 cases), 2a for urogenital surgery (9 publications, 197 cases), and 1-2a for plastic surgery (4 publications, 26 cases). One report did not belong to any categories. FGS in children is still in an early phase of adoption and development. We recommend using the IDEAL framework as a guide and suggest developing multicenter studies to define the standard guidelines, effectiveness, and outcomes.

Applications of Indocyanine Green-Guided Near-Infrared Fluorescence Imaging in Pediatric Minimally Invasive Surgery Urology: A Narrative Review

Background: Indocyanine green (ICG) is a fluorescent dye used for several indications in adult surgery, and, more recently, adopted also in the pediatric patients. This study aimed to review the literature published on the use of ICG near-infrared fluorescence (NIRF) in pediatric urology, to address its shortcomings and disadvantages and to detect the future perspectives. Materials and Methods: An electronic literature search of PubMed on all studies reporting use of ICG-NIRF in pediatrics was performed. We included only studies reporting ICG-NIRF application in minimally invasive surgery (MIS) for pediatric urology indications. Results: Forty-two articles reporting MIS procedures performed using ICG-NIRF in children were obtained, but only 15 studies that focused on urological applications of ICG-NIRF in children were included in this review. The included studies described use of ICG-NIRF for kidney malformations such as duplex system, kidney tumors, renal cysts, ureteral pathology, bladder malformations, varicocele, and lymph node sampling in tumors. The pediatric urological applications in which ICG-NIRF provided significant advantages included partial nephrectomy, lymphatics sparing varicocele repair, and oncological procedures. The ICG-NIRF use was clinically safe, without reported adverse systemic reactions in all pediatric series. The main drawback of this technology is the need of specific laparoscopic equipment such as camera system, light sources, and telescopes or the da Vinci Xi Robot, with the software for ICG-NIRF, Firefly^®, already integrated within. Conclusions: ICG-enhanced fluorescence-guided surgery is gaining growing popularity among pediatric surgeons due to the excellent results that have been published until now. ICG-NIRF technology has proven to be safe, easy to use, not time-consuming, cheap, and very effective to improve intraoperative view and surgical ability. Nonetheless, further evidence, including larger series, longer follow-up, and more specific assessments, is necessary to confirm the preliminary results and enlarge the applications.

Long lasting effect on testes following methylene blue injection in laparoscopic lymphatic sparing varicocelectomy

OBJECTIVE

Injection of methylene blue to testis has been shown to have adverse effect in animal studies but it is still being used frequently as lymphatic mapping agent during lymphatic sparing varicocelectomy in adolescent varicoceles. We aim to report postoperative ultrasound changes after subaortic injection of methylene blue in human testes.

STUDY DESIGN

A retrospective observational study of consecutive patients under 18 years old undergoing laparoscopic varicocelectomy from August 2017 to August 2021 was performed. Demographics such as age, symptoms, pre-operative testicular volume was collected. Primary outcome was change on testicular ultrasound at 3, 6, 12 months after the operation. Secondary outcome was testicular volume difference between affected and unaffected testes, and growth rate of affected testis at 1 year after the operation.

RESULTS

Fifty-eight patients were included, with median age of 15 years old (IQR 11-18 years). Thirty-one patients had non-lymphatic sparing varicocelectomy (Group A) and 27 patients had lymphatic sparing varicocelectomy (Group B). There was no statistical difference between the mean testicular volume difference between the two groups, but hydrocele rate was significantly higher in Group A (16% vs 0%, p = 0.03). In group B, 6 patients (22.2%, p = 0.005) developed testicular change detectable by ultrasound. No statistical difference could be demonstrated for median testicular size difference (between affected and unaffected testes) at 1 year between group with and without ultrasound change (-23% vs 0%, p = 0.36). Median follow up time was 20.4 months (IQR 5-32 months).

DISCUSSION

Varicocele treatments improve testicular volume and increase total sperm concentration and lymphatic sparing surgery significantly decreased post-operative hydrocele rates [2]. Different agents have been used to delineate lymphatic vessels and one commonly used agent is methylene blue [10,15-16]. However it has been shown in other animal studies that intraparenchymal injection of methylene blue to rat testis result in degenerative changes [18]. Our study is the first to describe post-operative changes of human testes on imaging after lymphatic sparing varicocelectomy with subdartoic injection of methylene blue. Six patients (22.2%) demonstrated new onset testicular changes on post-operative ultrasound. Although no statistically significant testicular volume reduction was seen in the group with change on imaging, these observations may serve as a surrogate marker for testicular injury or reduced testicular function. It will be desirable for future studies if we can investigate it further with hormonal markers or semen analysis after puberty has been reached.

CONCLUSION

Lymphatic sparing procedure reduced post-operative hydrocele in adolescent varicocele, however long-lasting effect on testis is evident with subdartoic injection of methylene blue. This agent must be used with caution and long term follow up of these patients are needed.

Fluorescence-Guided Surgery and Novel Innovative Technologies for Improved Visualization in Pediatric Urology

Fluorescence-guided surgery (FGS), three-dimensional (3D) imaging technologies, and other innovative devices are rapidly revolutionizing the field of urology, providing surgeons with powerful tools for a more complete understanding of patient-specific anatomy. Today, several new intraoperative imaging technologies and cutting-edge devices are available in adult urology to assist surgeons in delivering personalized interventions. Their applications are also gradually growing in general pediatric surgery, where the detailed visualization of normal and pathological structures has the potential to significantly minimize perioperative complications and improve surgical outcomes. In the field of pediatric urology, FGS, 3D reconstructions and printing technologies, augmented reality (AR) devices, contrast-enhanced ultrasound (CEUS), and intraoperative magnetic resonance imaging (iMRI) have been increasingly adopted for a more realistic understanding of the normal and abnormal anatomy, providing a valuable insight to deliver customized treatments in real time. This narrative review aims to illustrate the main applications of these new technologies and imaging devices in the clinical setting of pediatric urology by selecting, with a strict methodology, the most promising articles published in the international scientific literature on this topic. The purpose is to favor early adoption and stimulate more research on this topic for the benefit of children.

Intraoperative uses of near-infrared fluorescence spectroscopy in pediatric surgery: A systematic review

BACKGROUND

The application of near infrared spectroscopy (NIRS) imaging in surgery is growing. This study aimed to systematically review the literature to summarize the intraoperative uses of NIRS in pediatric surgery.

METHODS

A PRISMA-compliant literature search was conducted in PubMed, Embase, Scopus, and Web of Science from inception to February 2020. Title/abstract and then full-text screening were performed. The Oxford centre for Evidence Based Medicine tool (OCEBM) was used to evaluate the level of evidence of included studies.

RESULTS

Reviewers identified 53 articles. Of which, 34 studies (64.2%) were case-series and 11 (20.8%) were case reports. Most of the studies (n = 45, 84.9%) were level 4 on the OCEBM tool. The most common uses of NIRS were to visualize the biliary tree and to identify primary and metastatic malignant tissues. Other applications include assessment of perfusion of tissues including bowel anastomoses, and lymphatic surgery. Several advantages of the introduction of NIRS in pediatric surgery exist including having the potential to reduce operative time and intra/post-operative complications. Moreover, NIRS helps in detecting malignant tissues that can be missed by conventional imaging. However, NIRS has important limitations such as difficulty in identification of the biliary tree in obese patients or inflamed gallbladder, detection of small deeply localized malignant tissues, as well as the high cost.

CONCLUSIONS

NIRS is a promising modality that can be used intraoperatively to augment different pediatric surgical procedures. NIRS has important advantages and limitations compared to conventional surgery, however, more studies are required to evaluate its outcomes and cost-effectiveness.

LEVEL OF EVIDENCE

IV.

Indocyanine green fluorescent lymphography during open inguinal hernia repair in a patient who developed postoperative ultrasonic hydrocele: A case report

BACKGROUND

To our knowledge, no reports of indocyanine green (ICG) fluorescent lymphography during inguinal hernia repair currently exist. We report the case of a patient who underwent ICG fluorescent lymphography during open inguinal hernia repair.

CASE PRESENTATION

A 63-year-old man was referred to our department for treatment of a right inguinal hernia, during which an ICG lymphography was performed. The patient had a history of robot-assisted radical prostatectomy for prostate cancer. Following induction of general anesthesia, 0.25 mg of ICG was injected into the right testicle and the scrotum was gently massaged, after which an open inguinal hernia repair was performed. During the operation, fluorescence from the ICG was observed in two lymphatic vessels in the spermatic cord. The ICG fluorescent vessels were resected due to the strong adhesion between the lymphatic vessels and the hernia sac. ICG leakage was observed in the resected vessels. An open tension-free technique was performed using an open mesh plug. The patient was discharged one day postoperatively. The histological diagnosis of the resected vessel was a lymphatic vessel. He had a slight postoperative hydrocele that was detected at the follow-up clinic 10 days postoperatively during ultrasonic examination (ultrasonic hydrocele).

CONCLUSION

We report the use of ICG fluorescent lymphography during open inguinal hernia repair in a patient who developed postoperative ultrasonic hydrocele. This case may indicate a relationship between lymphatic vessel injury and hydrocele.

Image-guided surgery and novel intraoperative devices for enhanced visualisation in general and paediatric surgery: a review

Fluorescence guided surgery, augmented reality, and intra-operative imaging devices are rapidly pervading the field of surgical interventions, equipping the surgeon with powerful tools capable of enhancing the surgical visualisation of anatomical normal and pathological structures. There is a wide range of possibilities in the adult population to use these novel technologies and devices in the guidance for surgical procedures and minimally invasive surgeries. Their applications and their use have also been increasingly growing in the field of paediatric surgery, where the detailed visualisation of small anatomical structures could reduce procedure time, minimising surgical complications and ultimately improve the outcome of surgery. This review aims to illustrate the mechanisms underlying these innovations and their main applications in the clinical setting.

Management of adolescent varicocele

Varicocele is defined as an abnormal dilation and tortuosity of the internal spermatic veins found within the pampiniform plexus. It is a common finding in adolescents and adult men alike, however its diagnosis in the adolescent population poses different dilemmas in regard to indications for treatment than in adults. Failed Paternity is a clear-cut indication for repair in adult men attempting to father children. In adolescents, the physicians, family and patients must consider potential for future fertility problems which may or may not actually become of concern. Assessing the degree of negative effect of the varicocele on an adolescent's testicular health can also be difficult as teenagers typically are not asked to provide semen for analysis and thus surrogate markers for testicular health such as testicular size differentials must be used. Treatment options for the adolescent varicocele are similar to options in adult populations. While risks and benefits of various techniques can be considered, the gold standard for varicocele repair in adolescents has not been clearly defined. We aim to discuss diagnosis of varicocele, considerations for initiating treatment of varicocele in the adolescent, and techniques for management.

Technical standardization of ICG near-infrared fluorescence (NIRF) laparoscopic partial nephrectomy for duplex kidney in pediatric patients

Purpose

This study aimed to standardize the operative technique of indocyanine green (ICG) near-infrared fluorescence (NIRF) laparoscopic partial nephrectomy (LPN) and compare it with the standard technique.

Methods

In the last 4 years, we performed 22 LPN (14 right-sided, 8 left-sided) in children with non-functioning moiety of duplex kidney. Patients included 12 girls and 10 boys with a median age of 3.9 years (range 1–10). Patients were grouped according to the use of ICG-NIRF: G1 included 12 patients operated using ICG-NIRF and G2 included 10 patients receiving the standard technique. We standardized the technique of injection of ICG in three different steps.

Results

The median operative time was significantly lower in G1 [87 min (range 68–110)] compared with G2 [140 min (range 70–220)] (p = 0.001). One intra-operative complication occurred in G2. At post-operative ultrasound (US), the residual moiety was normal in all patients. An asymptomatic renal cyst related to the site of surgery was visualized at US in 8/22 (36%), with a significantly higher incidence in G2 (6/10, 60%) compared with G1 (2/12, 16.6%) (p = 0.001). Renogram demonstrated no loss of function of residual moiety. No allergic reactions to ICG occurred.

Conclusion

ICG-NIRF LPN is technically easier, quicker, and safer compared with the standard technique. The main advantages of using ICG-NIRF during LPN are the clear identification of normal ureter, vasculature of non-functioning pole, and demarcation line between the avascular and the perfused pole. The main limitation of ICG technology remains the need for specific laparoscopic equipment that is not always available.

Fluorescence imaging in pediatric surgery: State-of-the-art and future perspectives

BACKGROUND

The employment of fluorescence imaging has gained popularity in many fields of adult surgery where it has demonstrated great potentials to improve both surgical and oncological outcomes while minimizing anesthetic time and lowering health-care costs. However, the clinical application of fluorescence-guided surgery (FGS) in pediatrics is just at the initial phase.

MATERIAL AND METHODS

A systematic review of current clinical uses of FGS in pediatric surgery was performed along with a discussion on its advantages, limitations and future developments.

RESULTS

21 studies were included: 9 retrospective and 1 prospective study, 8 case reports, 2 case series and a review article reporting authors' institutional experience. Great emphasis was given to surgical resection of hepatoblastoma and its metastasis (n = 6), real-time imaging of the biliary tree (n = 3) and urogenital system (n = 2). Other current uses concern the assessment of blood perfusion (intestine, n = 3; myocutaneous flap, n = 1; transplanted liver, n = 1) and lymphatic flow imaging (n = 4).

CONCLUSION

Despite a paucity of clinical studies evaluating its role in pediatric surgery, FGS has shown promising results in helping guide tumor resection and improving the accuracy of anatomical delineation.

TYPE OF STUDY

Review article.

LEVEL OF CONFIDENCE

Level IV.

The Use of Indocyanine Green Fluorescence Angiography in Pediatric Surgery: A Systematic Review and Narrative Analysis

Purpose: Indocyanine green fluorescence angiography (ICG-FA) is a validated non-invasive imaging technique used to assess tissue vascularization and guide intraoperative decisions in many surgical fields including plastic surgery, neurosurgery, and general surgery. While this technology is well-established in adult surgery, it remains sparsely used in pediatric surgery. Our aim was to systematically review and provide an overview of all available evidence on the perioperative use of indocyanine green fluorescence angiography in pediatric surgical patients. Methods: We conducted a systematic review with narrative synthesis in conformity with the PRISMA guidelines using PubMed, Medline, All EBM Reviews, EMBASE, PsycINFO, and CINAHL COMPLETE databases to identify articles describing the perioperative use of ICG-FA in pediatric patients. Two independent authors screened all included articles for eligibility and inclusion criteria. We extracted data on study design, demographics, surgical indications, indocyanine green dose, and perioperative outcomes. We developed a risk of bias assessment tool to evaluate the methodological quality of included studies. Results: Of 1,031 articles retrieved, a total of 64 articles published between 2003 and 2020 were included reporting on 664 pediatric patients. Most articles were case reports and case series (n = 36; 56%). No adverse events related to ICG-FA were reported in the included articles. Risk of bias was high. We did not conduct a meta-analysis given the heterogeneous nature of the populations, interventions, and outcome measures. A narrative synthesis is presented. Conclusion: Indocyanine green fluorescence angiography is a safe imaging technology and its use is increasing rapidly in pediatric surgical specialties. However, the quality of evidence supporting this trend currently appears low. Case-control and randomized trials are needed to determine the adequate pediatric dose and to confirm the potential benefits of ICG-FA in pediatric surgical patients. Systematic Review Registration: This study was registered on Prospero a priori, identifier: CRD42020151981.

Near-Infrared fluorescence imaging using indocyanine green (ICG): Emerging applications in pediatric urology

BACKGROUND

Near-infrared fluorescence (NIRF) imaging with indocyanine green (ICG) has been recently adopted in pediatric minimally invasive surgery (MIS) in order to improve intra-operative visualization of anatomic structures and facilitate surgery.

OBJECTIVE

This study aimed to report our preliminary experience using ICG technology in pediatric urology using laparoscopy and robotics.

STUDY DESIGN

ICG technology was adopted in 57 laparoscopic or robotic urological procedures performed in our unit over a 24-month period: 41 (38 laparoscopic - 3 robotic) left varicocele repairs with intra-operative lymphography and 16 renal procedures (12 laparoscopic - 4 robotic) including 9 partial nephrectomies, 3 nephrectomies and 4 renal cyst deroofings.

RESULTS

The ICG solution was injected intravenously in renal procedures or into the testis body in case of varicocele repair. Regarding the timing of the administration, the ICG injection was performed intra-operatively in all cases and allowed the visualization of the anatomic structures in a matter of 30-60 s. The dosage of ICG was 0.3 mg/mL/kg in all indications. All procedures were completed laparoscopically or robotically without conversions. No adverse and allergic reactions to ICG and other complications occurred postoperatively.

DISCUSSION

This paper describes for the first time in pediatric urology that ICG-guided NIRF imaging may be helpful in laparoscopic and robotic procedures. In case of varicocele repair, ICG-enhanced fluorescence allowed to perform a lymphatic-sparing procedure and avoid the risk of postoperative hydrocele. In case of partial nephrectomy, ICG-guided NIRF was helpful to visualize the vascularization of the non-functioning moiety, identify the dissection plane between the two moieties (Fig. 1) and check the perfusion of the residual parenchyma after resection of the non-functioning pole. In case of renal cyst deroofing, ICG-guided NIRF aided to identify the avascular cyst dome and to guide its resection. No real benefits of using ICG-enhanced fluorescence were observed during nephrectomy.

CONCLUSION

Our preliminary experience confirmed the safety and efficacy of ICG technology in pediatric urology and highlighted its potential advantages as adjunctive surgical technology in patients undergoing laparoscopic or robotic urological procedures. Use of NIRF was also cost-effective as no added costs were required except for the ICG dye (cost 40 eur per bottle). The most common and useful applications in pediatric urology included varicocele repair, partial nephrectomy ad renal cyst deroofing. The main limitation is the specific equipment needed in laparoscopy, that is not available in all centers whereas the robot is equipped with the Firefly® software for NIRF.

Robotic-assisted laparoscopic artery-sparing varicocelectomy using indocyanine green fluorescence angiography: Initial experience

We reported our initial experience of robotic-assisted laparoscopic artery-sparing varicocelectomy using indocyanine green (ICG) fluorescence angiography in treatment of varicocele. A total of 45 varicocelectomies in 27 patients were performed. The mean operation time was 49.1 ± 8.5 min for unilateral and 65.6 ± 8.3 min for bilateral repair. 47.2 s after ICG injection, testicular artery (TA) was visualised. After an interval of 31.3 s, fluorescent veins were identified. Of all the 45 spermatic cords, 68.9% had a solitary artery, while 31.1% had 2 arteries. The mean hospital stay was 1.6 ± 0.9 days. Semen concentration and motility were significantly improved 6 months after surgery, no recurrence, hydrocele or testicular atrophy was observed. Our study demonstrated that robotic-assisted laparoscopic artery-sparing varicocelectomy using ICG fluorescence angiography is a safe, effective and promising technique in treatment of varicocele.

Fluorescence Imaging Using Indocyanine Green Dye in the Pediatric Population

OBJECTIVES

Fluorescence imaging using indocyanine green (ICG) allows for the intraoperative mapping of the vascular supply of various tissue beds. Although generally safe and effective, rare adverse effects have been reported including anaphylactoid reactions. The current study retrospectively reviewed our experience the intraoperative administration of ICG to pediatric patients.

METHODS

The anesthetic records of patients who received ICG over a 2-year time period were retrospectively reviewed and demographic, surgical, and medication data retrieved. Objective intraoperative data before and after the administration of ICG were also recorded. These included heart rate, systolic and diastolic blood pressures, oxygen saturation, and peak inflating pressure.

RESULTS

The study cohort included 100 patients with a median age of 12 years (9.5 ± 7.4 years) and the median weight being 44.5 kg (45.9 ± 36.9 kg). ICG was administered intravenously to all patients. In all cases, 2.5 mg/mL ICG solution was used, with a median dose of 1.1 mL (1.79 ± 1.8 mL). Eight patients received more than 1 dose of ICG, with no adverse respiratory or hemodynamic effects related to its use.

CONCLUSIONS

ICG fluorescence is an important imaging modality that can be safely used as an intraoperative adjunct to various surgical procedures in the pediatric population.

Laparoscopic or Robotic Deroofing Guided by Indocyanine Green Fluorescence and Perirenal Fat Tissue Wadding Technique of Pediatric Simple Renal Cysts

Purpose: To present the outcomes of the laparoscopic and robotic treatment of pediatric simple renal cysts with two novel modifications: the indocyanine green (ICG) fluorescence and the perirenal fat tissue wadding technique. Methods: Between 2012 and 2019, 13 patients with solitary renal cysts were treated through minimally invasive approach. Preoperative work-up included ultrasonography and computed tomography or magnetic resonance. A cyst deroofing was performed in all cases. In the last 3 cases, the ICG fluorescence technique enabled a clear identification and safe puncture of the cyst dome. Five cysts were filled with perirenal fat tissue after deroofing. Results: Thirteen patients (9 boys) were treated through laparoscopic (6 patients), retroperitoneoscopic (3 patients), or robotic approach (4 patients). Median age was 8 years (5-15 years). The median cyst size was 70 mm (42-160 mm). Eight cysts were located in the right kidney. All cysts were progressive and symptomatic. Thirteen cysts (100%) were graded as type II according to the Bosniak classification. No conversion was recorded. The median operative time for laparoscopy was 50 minutes (35-90 minutes) and 85 minutes for robotics (65-120 minutes) including surgical and docking time. No intraoperative complications occurred. The median hospital stay was 2 days (36-96 hours). No residual liquid was detected on follow-up after deroofing and fat tissue wadding technique. Conclusions: Cyst deroofing is an effective and durable treatment for symptomatic simple renal cysts. Robotics enables excellent tissue dissection and ergonomics. The perirenal fat tissue wadding of the cyst seems to reduce the recurrence rate. The ICG fluorescence technique allows for better identification of the cyst and safer surgical procedure.

Image-Guided Pediatric Surgery Using Indocyanine Green (ICG) Fluorescence in Laparoscopic and Robotic Surgery

Background: Indocyanine green (ICG)-guided near-infrared fluorescence (NIRF) has been recently adopted in pediatric minimally invasive surgery (MIS). This study aimed to report our experience with ICG-guided NIRF in pediatric laparoscopy and robotics and evaluate its usefulness and technique of application in different pediatric pathologies. Methods: ICG technology was adopted in 76 laparoscopic and/or robotic procedures accomplished in a single division of pediatric surgery over a 24-month period (January 2018-2020): 40 (37 laparoscopic, three robotic) left varicocelectomies with intra-operative lymphography; 13 (10 laparoscopic, three robotic) renal procedures: seven partial nephrectomies, three nephrectomies, and three renal cyst deroofings; 12 laparoscopic cholecystectomies; five robotic tumor excisions; three laparoscopic abdominal lymphoma excisions; three thoracoscopic procedures: two lobectomies and one lymph node biopsy for suspected lymphoma. The ICG solution was administered into a peripheral vein in all indications except for varicocele and lymphoma in which it was, respectively, injected into the testis body or the target organ. Regarding the timing of the administration, the ICG solution was administered intra-operatively in all indications except for cholecystectomy in which the ICG injection was performed 15-18 h before surgery. Results: No conversions to open or laparoscopy occurred. No adverse and allergic reactions to ICG or other postoperative complications were reported. Conclusions: Based upon our 2 year experience, we believe that ICG-guided NIRF is a very useful tool in pediatric MIS to perform a true imaged-guided surgery, allowing an easier identification of anatomic structures and an easier surgical performance in difficult cases. The most common applications in pediatric surgery include varicocele repair, difficult cholecystectomy, partial nephrectomy, lymphoma, and tumors excision but further indications will be soon discovered. ICG-enhanced fluorescence was technically easy to apply and safe for the patient reporting no adverse reactions to the product. The main limitation is represented by the specific equipment needed to apply ICG-guided NIRF in laparoscopic procedures, that is not available in all centers whereas the ICG system Firefly® is already integrated into the robotic platform.

Clinical application and technical standardization of indocyanine green (ICG) fluorescence imaging in pediatric minimally invasive surgery

PURPOSE

We reported our preliminary experience using ICG fluorescence in pediatric minimally invasive surgery (MIS) with the aim to standardize indications, dose, timing, and modality of administration of ICG according to different organs.

METHODS

ICG technology was adopted in 46 MIS procedures performed in our unit over the last 18 months: 30 left varicocele repairs; 5 cholecystectomies in obese adolescents; 3 tumor excisions; 3 nephrectomies; 2 partial nephrectomies; 3 lymphoma excisions. ICG solution was injected intravenously in all cases except for varicocelectomy in which it was injected into the testis. The ICG injection was performed intra-operatively in all cases except for cholecystectomy in which it was injected 18 h prior to the procedure.

RESULTS

All procedures were completed laparoscopically without conversions or intra-operative complications. No adverse or allergic reactions to ICG were reported.

CONCLUSION

Our preliminary experience showed that ICG fluorescence is a safe, useful, and versatile technique to adopt in pediatric MIS to achieve a better identification of anatomy and an easier surgical dissection or resection in challenging cases. Currently, the main indications are varicocelectomy, difficult cholecystectomy, tumor excision, nephrectomy, and partial nephrectomy. The main limitation is the needing of a special equipment to use ICG technology.

Application of indocyanine green in pediatric surgery

The use of near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) has gained popularity in many fields in adult surgery, such as sentinel lymph node mapping, intra-operative solid tumor identification, and organ perfusion assessment. However, the clinical application of ICG in pediatric surgery is just at the beginning. This review paper presents the advantages, current applications and potential developments of NIR fluorescence imaging with ICG in our field.