The impact of Geometric mean Renography Assessment for INcreased accuracy – A comparative study with standard diuretic renography (GRAIN study)

Certificate Output Instructions

For best output, select "Paper Size" as "A4" and "Margin" as "0" or "None".

To save or print to PDF, please select Print Destination > Save as PDF, enable Background Graphics under "More Settings", then click "Save".

Presented the abstract " "
(Abstract co-author(s): )

Back

E-Poster Presentation

During the congress, E-Posters will be accessible to all participants on the congress website 24/7, as well as in the E-poster stations in the congress center.

Preparing your E-Poster

Please review the E-Poster format requirements carefully when preparing your E-Poster. Should your E-Poster not meet the mentioned requirements, it may not be displayed as described above.

E-Poster Submission Deadline

Please prepare and upload your E-Poster no later than March 14, 2026 11.59PM CET. After this date, you will no longer be able to prepare and upload your E-poster and it will not be displayed and accessible on the congress website.

E-Poster Format Requirements

PDF file
Layout: Portrait (vertical orientation)
One page only (Dim A4: 210 x 297mm or PPT)
E-Poster can be prepared in PowerPoint (one (1) PowerPoint slide) but must be saved and submitted as PDF file.
File Size: Maximum file size is 2 Megabytes (2 MB)
No hyperlinks, animated images, animations, and slide transitions
Language: English
Include your abstract number
E-posters can include QR codes, tables and photos

E-Poster

https://storage.unitedwebnetwork.com/files/1099/ff86d0a899b2bbee2d0b540ed8683fc9.pdf

Abstract Title *

The impact of Geometric mean Renography Assessment for INcreased accuracy – A comparative study with standard diuretic renography (GRAIN study)

Please follow the instructions below to input your abstract title.

Abstract titles should be brief and reflect the content of the abstract.

The title will not be accepted if it exceeds 25 words.
Type in CAPITAL LETTERS.
Lowercase may be used for abbreviations only, for example, mRNA.

Co-author 1

Sadollah Abedini sadollah.abedini@siv.no Vestfold Hospital Trust Kidney disease Tønsberg Norway *

Co-author 2

Erling Halvorsen erling.halvorsen@siv.no Vestfold Hospital Trust Nuclear Medicine Tønsberg Norway -

Co-author 3

Co-author 4

Co-author 5

Co-author 6

Co-author 7

Co-author 8

Co-author 9

Co-author 10

Co-author 11

Co-author 12

Co-author 13

Co-author 14

Co-author 15

Introduction

Posterior-only diuretic renography can misestimate split renal function (SRF) when kidney depths differ. The geometric mean (GM) of simultaneous anterior/posterior views corrects depth-related attenuation but is not routine in adult practice. We quantified the clinical impact of GM versus the posterior approach.

Methods

In 71 adults (35 female, 36 male) undergoing diuretic renography, SRF was computed three ways: posterior-only, manual GM, and automated GM. Manual GM used tight parenchymal contours with a sector-based curved background band and area-normalized background subtraction; GM was computed per frame from background-corrected anterior/posterior counts. Clinically relevant reclassification thresholds were pre-specified as >5 and >10 percentage points (pp) between manual GM and posterior SRF. Non-parametric comparisons used the Wilcoxon signed-rank test.

Results

Versus posterior-only, manual GM shifted SRF by +3.0 pp (right) and −3.0 pp (left) (both p<0.001). Differences >10 pp occurred in 19% (right) and 16% (left); >5 pp in 33% and 28%, respectively. Bland–Altman plots showed a consistent bias (GM higher for right, lower for left) with wide limits of agreement reflecting inter-patient variability. Automated GM mirrored manual GM trends.

Conclusion

Method choice materially alters adult SRF estimates. GM correction reduces depth-related bias and reclassifies a clinically important subset, with implications for side selection and surgical decision-making. Given accuracy, speed, and reproducibility, automated GM should replace posterior-only analysis as the default in adult diuretic renography, with manual GM reserved for quality control in flagged cases.

Kewords