India Ink Tattooing of Ureteroenteric Anastomoses

Round 1

Reviewer 1 Report

This is a prospective single center study of patients undergoing open ileal conduit urinary diversion randomized to India Ink injections vs saline near the ureteroileal anastomosis site to assess anastomosis identification rate and safety. They found a non-significant higher rate of identification in the Ink group but also higher than expected rate of stricture so the trial was closed early. Other complication events appear similar between groups.

Overall, this is a well-designed study that ended early due to safety concerns, with a thoughtful discussion by the authors. Since there is a lack of prior data in this area I believe these results should be published, and can serve as initial protocol for future reference.

Major comments:

-       While the difference in anastomosis detection rate is not different, was time to identification measured? Sometimes while the anastomosis is found eventually it can take a while, and if Ink allowed faster identification that would be worth reporting.

-       Methods, line 76: please specify the type of anastomosis: did every surgeon use Bricker type?

-       Methods, line 81: is the gravity loopogram and looposcopy standard post-op protocol or only done as part of this study to increase event detection rate?

-       As part of the discussion, please comment on since the primary endpoint was not significantly different and there were safety concerns, do the authors think this technique should be abandoned or modified and re-attempted?

Minor comments:

-       Abstract, line 18: define UEAS prior to using abbreviation

-       Results, line 156: the infection rate is higher than average for literature. Please consider discussing potential reasons. Could it be due to more conduit manipulation for study purposes?

Author Response

     While the difference in anastomosis detection rate is not different, was time to identification measured? Sometimes while the anastomosis is found eventually it can take a while, and if Ink allowed faster identification that would be worth reporting.
Those performing the looposcopy did feel that it was faster to find the orifice in the patients with the India ink tattoo as they had a starting place to for their search.  However, the time to orifice identification was not recorded in this study.

Methods, line 76: please specify the type of anastomosis: did every surgeon use Bricker type?

Yes, all anastomoses were done in Bricker fashion. (Line 80)

Methods, line 81: is the gravity loopogram and looposcopy standard post-op protocol or only done as part of this study to increase event detection rate?

We clarified in the manuscript that gravity loopogram is part of our standard protocol to assess for structures postoperatively, looposcopy was used the study to assess for the presence of India ink post-operatively in addition to being employed in the event no reflux was seen on loopogram. (lines 83-88).

As part of the discussion, please comment on since the primary endpoint was not significantly different and there were safety concerns, do the authors think this technique should be abandoned or modified and re-attempted?

We added to the manuscript while we would be unlikely to reattempt using India Ink, it would not be unreasonable to attempt with a smaller gauge needle and a smaller single dot of ink. (line 241-245)

Abstract, line 18: define UEAS prior to using abbreviation

Added "ureteroenteric anastomotic stricture". (line 18)

Results, line 156: the infection rate is higher than average for literature. Please consider discussing potential reasons. Could it be due to more conduit manipulation for study purposes?

In this study, 1 patient (10%) from the ink cohort had a post operative infection compared to 0 from the control group.  While this is higher than rates frequently reported in the literature, we did not feel that we could draw conclusions based on a single patient.  Undergoing an extra endoscopic procedure compared to standard post-operative protocol does certainly increase infection; however, the present study did not allow us to extrapolate on this finding.

Reviewer 2 Report

Overall, this article presents the findings of the study in a clear and concise manner. However, the following suggestions could be made to improve the quality.

1. Provide more context and background information on why India ink is used.

2. Consider providing recommendations for future research or clinical practice, such as the need for alternative visualization methods.

3. The conclusion could also include the potential consequences of not using India ink in urinary diversions.

Author Response

Provide more context and background information on why India ink is used.

We included additional context and background on the use of India ink in the urinary track and gastrointestinal tract as well as the application of India ink the the urinary tract in the introduction. (line 32-44 and 67-85)

Consider providing recommendations for future research or clinical practice, such as the need for alternative visualization methods.

We added to the manuscript while we would be unlikely to reattempt using India Ink, it would not be unreasonable to attempt with a smaller gauge needle and a smaller single dot of ink. (line 241-245)

The conclusion could also include the potential consequences of not using India ink in urinary diversions.

Without using a method, such as India ink, to improve ureteral anastomotic visualization, surgeons are left practicing as they are now.  While it can be difficult and time-consuming to locate an ureteral anastomosis endoscopically, using open procedures to address upper tract pathology is still a viable and widely-used option.  The development of a means to increase identification of the ureteral anastomotic site endoscopically has the potential to reduce procedure time and improve patient outcomes; however, this should not come with an added risk to patients on account of the technique used. (line 248-256)

Reviewer 3 Report

First of all, I wanted to congratulate the authors for the honesty of the article and for its methodology. I think that works like this should be published, even though the results are not positive for what the group is looking for, although the identification of the anastomosis was effective.

Methodologically, I consider that it is well designed, it is an interesting study for groups that perform cystectomies and, despite its limitations, such as the sample size, I consider that it is of great help to continue with similar lines of research.

I encourage the authors to continue researching in this field.

Author Response

Thank you!

Author Response File: Author Response.pdf