Tag Archive for: intracorporeal urinary diversion

Posts

Article of the week: Use of indocyanine green to minimise uretero‐enteric strictures after robotic radical cystectomy

Every week, the Editor-in-Chief selects an Article of the Week from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an editorial and a visual abstract written by members of the urological community, and a video produced by the authors. These are intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation. 

If you only have time to read one article this week, it should be this one.

Use of indocyanine green to minimise uretero‐enteric strictures after robotic radical cystectomy

Nariman Ahmadi, Akbar N. Ashrafi, Natalie Hartman, Aliasger Shakir, Giovanni E. Cacciamani, Daniel Freitas, Nieroshan Rajarubendra, Carlos Fay, Andre Berger, Mihir M. Desai, Inderbir S. Gill and Monish Aron

 

USC Institute of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA

 

Abstract

Objective

To evaluate the impact of indocyanine green (ICG) for assessing ureteric vascularity on the rate of uretero‐enteric stricture formation after robot‐assisted radical cystectomy (RARC) with intracorporeal urinary diversion (ICUD).

Patients and methods

We identified 179 patients undergoing RARC and ICUD between January 2014 and May 2017, and divided the patients into two groups based on the utilisation of ICG for the assessment of ureteric vascularity (non‐ICG group and ICG group). We retrospectively reviewed the medical records to identify the length of ureter excised. Demographic, perioperative outcomes (including 90‐day complications and readmissions), and the rate of uretero‐enteric stricture were compared between the two groups. The two groups were compared using the t‐test for continuous variables and the chi‐squared test for categorical variables. A P < 0.05 was considered statistically significant.

Results

A total of 132 and 47 patients were in the non‐ICG group and the ICG group, respectively. There were no differences in baseline characteristics and perioperative outcomes including operating time, estimated blood loss, and length of stay. The ICG group was associated with a greater length of ureter being excised during the uretero‐enteric anastomosis and a greater proportion of patients having long segment (>5 cm) ureteric resection. The median follow‐up was 14 and 12 months in the non‐ICG and ICG groups, respectively. The ICG group was associated with no uretero‐enteric strictures compared to a per‐patient stricture rate of 10.6% and a per‐ureter stricture rate of 6.6% in the non‐ICG group (P = 0.020 and P = 0.013, respectively).

Conclusion

The use of ICG fluorescence to assess distal ureteric vascularity during RARC and ICUD may reduce the risk of ischaemic uretero‐enteric strictures. The technique is simple, safe, and reproducible. Larger studies with longer follow‐up are needed to confirm our findings.

Editorial: Reducing the rate of uretero‐enteric strictures after robot‐assisted cystectomy: a green light for immunofluorescence?

In the current edition of the BJUI, Ahmadi et al. [1] from the University of Southern California describe their experience with the use of indocyanine green (ICG) during robot‐assisted radical cystectomy (RC); specifically, they discuss its potential utility in assessing the vascularity of distal ureteric segments ahead of anastomosis to the bowel segment during urinary diversion.

Benign postoperative ureteric strictures are thought to be largely attributable to inadequate vascularization of the distal ureter on account of its segmental blood supply. Despite meticulous dissection technique and avoidance of traction or anastamotic tension, many series still report a stricture rate in the order of 10% in both open and minimally invasive surgery. Conventionally, the left ureter is associated with a higher risk because of its more extensive mobilization and longer trajectory behind the recto‐sigmoid.

Notably, there were early indications in the 1990s that minimally invasive surgery had the potential to increase the risk of ureteric complications, and this was highlighted by various authors pioneering the introduction of laparoscopic live donor nephrectomy [2,3,4]. Surgeons at that time cited magnification as a potential culprit, with intra‐operative views suggesting a well‐preserved peri‐ureteric tissue bundle but an ex vivo ureter that appeared more denuded when examined with the ‘naked eye’.

In the present study, the theoretical construct applied was that the use of ICG could potentially remove the subjectivity of the surgeon’s assessment of distal ureteric vascularity and replace it with a more objective visual guide through the use of immunofluorescence after administration of ICG. The study design was an interrupted time series rather than a randomized trial, but was set in the context of a unit where all surgeons reported over a decade of experience each in performing robot‐assisted RC in a high‐volume setting.

Indocyanine green is a fluorescent, non‐toxic tracer that can be visualized with an infra‐red camera but remains non‐visible in conventional white light. It established its initial position within the robotic theatre by being popularized for the assessment of vascularity of renal tumours, particularly during nephron‐sparing surgery [5]. Once injected, there is an initial arterial phase followed by a later tissue perfusion phase where the tissue itself can be seen to fluoresce if vascularized adequately. The initial arterial phase is rapid (30 s), followed several minutes later by the perfusion phase.

After its introduction at the USC Institute of Urology, surgeons used the infra‐red findings of ICG administration to guide the length of distal ureteric resection in preparation for the uretero‐enteric anastomosis. Ureteric stricture rates were assessed at 12–14 months postoperatively based on clinical or radiological suspicion of stricturing. Confirmatory tests included a loopogram or cystogram and functional nuclear imaging. In some cases, nephrostomy and antegrade studies were performed.

The study found a marked reduction in stricture rate, from 10.6% in the non‐ICG group to an undetectable rate in the ICG group at this stage of follow‐up. This was associated with a greater length of resected ureteric segment in the ICG group compared to the non‐ICG group.

If viewed in the context of a single‐centre feasibility study, then the findings suggest a technique that is safe, is reproducible and has the potential to markedly reduce a challenging and not insignificant postoperative complication of RC. The findings would also support the authors’ theoretical construct that ischaemia and fibrosis are the key drivers of ureteric stricturing following RC.

It is of course acknowledged in the paper that further studies across multiple centres are needed for validation, but the findings so far would indicate that extending its further evaluation is warranted. It will also be of interest to see whether surgeons experienced in this technique would eventually develop the expertise to identify a poorly perfused ureter without the need for ICG based on pattern recognition and or greater confidence in excising longer ureteric segments.

References

  1. Ahmadi NAshrafi ANHartman N et al. Use of indocyanine green to minimise uretero‐enteric strictures after robotic radical cystectomy. BJU Int 2019124302– 7
  2. Ratner LECisek LJMoore RGCigarroa FGKaufman HSKavoussi LRLaparoscopic live donor nephrectomy. Transplantation 1995601047– 9
  3. Philosophe BKuo PCSchweitzer EJ et al. Laparoscopic vs open donor nephrectomy: comparing ureteral complications in the recipients and improving the laparoscopic technique. Transplantation 199968497– 502
  4. Kavoussi LRLaparoscopic donor nephrectomy. Kidney Int 2000572175– 86
  5. Tobis SKnopf JKSilvers CR et al. Near infrared fluorescence imaging after intravenous indocyanine green: initial clinical experience with open partial nephrectomy for renal cortical tumors. Urology 201279958– 64

 

© 2019 BJU International. All Rights Reserved.