Inter-observer reproducibility in reporting on renal drainage in children with hydronephrosis: a large collaborative...

Area of Science:

• Nuclear Medicine
• Pediatric Nephrology
• Radiology

Background:

• Technetium-99m mercaptoacetyltriglycine (99mTc MAG3) renography is a key imaging modality for assessing renal drainage in children.
• Evaluating drainage quality is crucial for diagnosis and management, but subjective interpretation can lead to variability.

Purpose of the Study:

• To assess the inter-observer reproducibility of reporting renal drainage in pediatric 99mTc MAG3 renography.
• To identify factors contributing to discrepancies in drainage assessment among nuclear medicine specialists.

Main Methods:

• Fifty-seven observers from five continents evaluated 23 pediatric 99mTc MAG3 renograms with varying drainage patterns.
• Data included images, curves, and quantitative parameters, with observers classifying drainage as good, partial, or poor.

Main Results:

• Significant inter-observer bias was observed, with a tendency for some to over-report good drainage and others to over-report poor drainage.
• Reproducibility was poor, with less than 80% agreement among observers for over half of the kidneys assessed.
• Discrepancies arose from unclear definitions between drainage categories, inconsistent inclusion of micturition/positional effects, and challenges with flat curves or small kidneys.

Conclusions:

• There is a critical need for standardized guidelines in evaluating and reporting renal drainage quality during pediatric 99mTc MAG3 renography.
• Standardization will enhance diagnostic accuracy and improve consistency in patient management.