# Discrepancies between primary and secondary interpretations of pediatric nuclear medicine imaging examinations

## TL;DR

This study shows that 17% of pediatric nuclear medicine exams had meaningful changes after a second expert review, which could affect patient care.

## Contribution

The study quantifies the clinical impact of secondary interpretations in pediatric nuclear medicine imaging.

## Key findings

- 17% of 358 exams had changes that could impact clinical management.
- 40% of these changes involved the presence or absence of malignant disease.
- Referring providers found value in secondary interpretations even when they confirmed the initial results.

## Abstract

Requests for secondary interpretation of imaging examinations adds clinical work and generates additional charges.

To understand the impact of secondary interpretations of pediatric nuclear medicine examinations at a quaternary academic center.

In this IRB approved study, we retrospectively reviewed nuclear medicine examinations submitted for secondary interpretation by a pediatric radiologist with a nuclear medicine focus at our institution between 08/2019 and 08/2024. A single reviewer compared the primary and secondary reports to identify discrepancies that would likely impact clinical management, and discrepancies were confirmed by additional reviewers. Pediatric hematology/oncology faculty (n=29) and fellows (n=18) at our institution were surveyed to understand requests for, and the impact of, secondary interpretations. Results are summarized with descriptive statistics.

Three hundred fifty-eight examinations (median patient age=8 years) were included, 237 were 18F-FDG PET body scans, 97 were 123I-MIBG scans, and 24 were other examinations. Secondary interpretations yielded meaningful changes in 17% (60/358). Of these, 20% (12/60) changed from negative/normal to positive, 20% (12/60) changed from positive to negative/normal, and 57% (34/60) included additional positive findings/diagnoses. Sixteen survey responses (34%; n=16/47 response rate) were received, with providers indicating that secondary interpretations were clinically useful even when they agreed with the primary impression.

Secondary interpretation of pediatric nuclear medicine examinations by pediatric radiologists with nuclear medicine focus resulted in changes that have potential impact on clinical management in 17% of cases. Secondary interpretations completely changed the impression regarding the presence or absence of malignant disease in 40% of these cases. Referring providers identified benefit in secondary interpretations even when they confirmed the primary impression.

The online version contains supplementary material available at 10.1007/s00247-025-06441-w.