Ultrasound for primary imaging of congenital hypothyroidism

Abstract

Objective: The purpose of this study was to retrospectively evaluate the use of sonography as the primary imaging modality for congenital hypothyroidism (CH).

Materials and methods: From our regional registry, we reviewed the cases of patients for whom either sonography or (99m)Tc-pertechnetate scanning was performed for CH between 2003 and 2010. Ultrasound studies were reviewed for presence, size, echotexture, vascularity, and location of the thyroid gland. Technetium-99m-pertechnetate scans were evaluated for the presence and location of the thyroid gland. The ultrasound studies were compared with the (99m)Tc-pertechnetate scans. We assessed the use of ultrasound as the primary imaging modality for the evaluation of CH.

Results: We identified the cases of 124 patients (89 girls, 35 boys). Ultrasound studies were available for 121 patients, and (99m)Tc-pertechnetate studies for 62 patients. Three patients were examined only by (99m)Tc-pertechnetate scanning. The final imaging results were normal location with normal size or diffuse enlargement of the thyroid gland (n = 47), sublingual thyroid gland (n = 49), agenesis (n = 18), hypoplasia (n = 8), and hemiagenesis (n = 2). Compared with (99m)Tc-pertechnetate scanning, ultrasound had high (100%) specificity and low (44%) sensitivity for detection of sublingual thyroid gland.

Conclusion: We suggest using ultrasound as the primary imaging modality for guiding the treatment of children with CH, potentially decreasing radiation exposure and cost.