Thyroid ultrasonography versus scintigraphy for establishing a stepwise imaging approach in pediatric patients with thyroid dysgenesis in resource-limited settings.

Abstract

Introduction: Thyroid scintigraphy and ultrasonography are the two primary imaging modalities widely used for thyroid visualization in pediatric patients with congenital hypothyroidism (CH). These modalities provide complementary information. In resource-limited settings, adopting a stepwise approach for selecting the initial imaging modality is essential.

Aim of the study: To compare the diagnostic performance of thyroid ultrasonography, thyroid scintigraphy, and combined modalities in categorizing the type of thyroid dysgenesis.

Material and methods: This cross-sectional study included 56 patients with CH due to thyroid dysgenesis. 99mTc thyroid scintigraphy was performed in all patients at diagnosis. Participants underwent thyroid ultrasonographic examination.

Results: Ultrasonography showed the highest sensitivity in diagnosing thyroid hypoplasia (75%) but lacked sensitivity in detecting ectopic thyroid. Thyroid scintigraphy sensitivity was highest for diagnosing ectopic glands and agenesis (100%) but less sensitive for hypoplasia (54.5%). Combining both imaging modalities demonstrated a sensitivity and accuracy of 100% across all types of dysgenesis.

Conclusions: Combined thyroid scintigraphy and ultrasonography demonstrated superior diagnostic accuracy, enabling precise characterization of thyroid dysgenesis. If the combined approach is not feasible, initiating thyroid scintigraphy is recommended as the first-line imaging modality and neck ultrasonography serves as a complementary second line imaging technique.