Assessing the Feasibility of Using Methylene Blue in Identifying Ureters During Colorectal Surgery

What Was Tested

This registered phase 4 trial tested Methylene blue (non-peptide stack partner).

This study will assess whether methylene blue fluorescence imaging can help surgeons identify the ureters during colorectal surgery.

Methylene blue, given through a vein during the operation, is taken up and excreted by the kidneys, allowing the ureters to appear under a special fluorescence camera system.

The study will include adults undergoing open, laparoscopic, or robotic colorectal surgery at Prince of Wales Hospital.

It had 1 arm (groups): Methylene Blue Fluorescence Imaging Arm (experimental).

Intravenous Methylene Blue with Fluorescence Imaging for Ureter Identification.

The registry classes the interventions as device and drug.

Who Took Part

20 planned participants were the target.

It was open to people of any sex aged from 18 years with no upper age limit.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Aged ≥18 years. Scheduled to undergo open, laparoscopic or robotic colorectal surgery, including right colectomy, extended right colectomy, left colectomy, high anterior resection, low anterior resection, abdominoperineal resection, subtotal colectomy and total colectomy.

The full record lists 2 inclusion and 7 exclusion criteria; among the exclusions: unable to understand the aims and objectives of this study and unable to give consent for participation; known allergy to methylene blue; taking selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, or tricyclic antidepressants (risk of serotonin syndrome).

How the Study Was Run

The set-up was single-group and open-label.

Everyone knew when Methylene blue (non-peptide stack partner) was being given (open label), which is simpler to run but leaves more room for expectations to affect what is reported.

Everyone received the same intervention, so there was no separate comparison group inside the trial.

It started in 2026-10-01 with completion listed for 2027-10-01.

Its stated primary purpose is device feasibility.

What Was Measured

The main thing measured (primary outcome): Proportion of cases in which fluorescence imaging with methylene blue is deemed helpful for identifying the index ureter.

What This Means in Plain Language

Put simply, this is a phase 4 trial of Methylene blue (non-peptide stack partner) in 20 people.

Its size is small, so on its own it can only give an early look.

Its status is not yet recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Methylene blue (non-peptide stack partner) compound page, all human trials.