Evidence map›Paper›PMID 41891010›Full record

ArticlemedRxiv : the preprint server for health sciences2026

An intraoperative methylene blue test can guide patient selection for totally tubeless PCNL.

Jean Lee, Natalie Meyer, Dyandra Parikesit, Brian Dick, Jorge Mena, Tad Manalo, Hunter Flores, Ryan Ferreira, Mustafa Saeed, Melissa Wong and 4 more

Abstract readPreprint
In one paragraph

Article in medRxiv : the preprint server for health sciences, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors.

Jean LeeDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.ORCID 0009-0000-1715-2551
Natalie MeyerDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.ORCID 0009-0004-0756-9635
Dyandra ParikesitUrology Medical Staff Group, Universitas Indonesia Hospital, Depok, Indonesia.ORCID 0000-0001-5779-2713
Brian DickDepartment of Urology, University of California San Francisco.ORCID 0000-0002-6330-4648
Jorge MenaDepartment of Urology, University of California San Francisco.ORCID 0000-0002-7372-243X
Tad ManaloDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.ORCID 0000-0002-5189-6156
Hunter FloresDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.
Ryan FerreiraSchool of Medicine, University of California San Francisco.ORCID 0009-0005-3734-0943
Mustafa SaeedDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.ORCID 0009-0005-7158-6453
Melissa WongDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.
Marshall StollerDepartment of Urology, University of California San Francisco.ORCID 0000-0002-8298-3586
Thomas ChiDepartment of Urology, University of Alabama Birmingham.ORCID 0000-0003-2127-2673
Wilson SuiDepartment of Urology, University of Michigan.ORCID 0000-0002-1819-6596
Heiko YangDepartment of Surgery (Urology), University of Colorado Anschutz Medical Campus.ORCID 0000-0002-1278-0150

Funding

NRSA Training CoreTL1DK139565 · NIDDK · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI PHILIP A BEACHY, Chi-yuan Hsu · 2023 to 2026
$5.1M
Professional Development CoreU2CDK133488 · NIDDK · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI Marsha J Treadwell · 2023 to 2026
$4.1M
NIDDK NIH HHS TL1 DK139565NIDDK NIH HHS U2C DK133488
6 · The paper itself

Abstract

Introduction and Objective: Totally tubeless percutaneous nephrolithotomy (PCNL) has been demonstrated to be feasible and safe, particularly for mini-PCNL. Having an objective test to guide patient selection could improve confidence in this practice and facilitate broader adoption. The purpose of this study was to evaluate the utility of an intraoperative methylene blue test to determine candidacy for totally tubeless PCNL. Methods: Adult patients undergoing PCNL at four institutions were included in this study. Patients with prior reconstructive surgery, chronic pain, or requiring ureteral dilation were excluded. After stone clearance, 10 mL methylene blue (MB) dye was injected into the percutaneous access tract. A positive test ("pass") was defined as visualization of blue dye in the bladder catheter within two minutes of injection. In some standard PCNL cases, totally tubeless management was simulated by placement of a capped nephrostomy tube. Post-operative complications within 7 days were evaluated as the primary outcome. Results: The intraoperative MB test was performed in 91 PCNL cases: 60 mini-PCNLs (16 Fr access) and 31 standard PCNLs (24+ Fr access). Mini-PCNL cases were more likely to pass the MB test compared to standard PCNL cases (75% vs 38.7%, p = 0.001). Of the 45 mini-PCNL subjects who passed, 40 were left totally tubeless, resulting in two minor complications (urinary retention, obstructing ureteral stone fragment). In the standard PCNL cohort, 12 passed the MB test. Five were left totally tubeless and 3 simulated totally tubeless management with capped nephrostomy tubes; one subject had a transient postoperative creatinine elevation, and one required uncapping for steinstrasse. There were no other obstructive or infectious complications, and no surgical reintervention was required. Conclusions: An intraoperative methylene blue test is a simple test with high positive-predictive value to determine candidacy for totally tubeless PCNL in real time for both mini and standard PCNLs.

Indexed as

intraoperative decision-makingmethylene blue testmini-PCNLnephrolithiasisPercutaneous nephrolithotomytotally tubeless PCNL

Identifiers

PMID41891010
PMCPMC13015675

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.