Ultrasonographic and scintigraphic findings of thyroid hemiagenesis in a child: report of a rare male case

Abstract

Thyroid hemiagenesis is a rare congenital anomaly in which one lobe of thyroid gland fails to develop. It is much rarer in males. There is a higher incidence of associated thyroid disorders in patients with thyroid hemiagenesis; therefore early and prompt diagnosis is important for children. We present the ultrasonographic and scintigraphic findings of thyroid hemiagenesis in an eight-year-old-boy. On ultrasonography (US), left lobe of the thyroid gland could not be demonstrated and the right lobe showed minimal hyperplasia. Its echogenicity was normal and no nodule was seen. On thyroid scintigraphy, left lobe of thyroid gland or any ectopic thyroid tissue could not be demonstrated, while the right lobe showed minimal hyperplasia. Without performing any invasive procedure, we enrolled the child in a follow-up program with the guidance of US and scintigraphy, which were effective both in making the final diagnosis of thyroid hemiagenesis and in evaluating the current status of the present thyroid tissue. In conclusion, if only one thyroid lobe is detected in a pediatric case initially with US or scintigraphy, the diagnosis of thyroid hemiagenesis should be suggested and, before any unnecessary or invasive attempt, the other complementary method (scintigraphy/US) should be performed.

Figure 1

On transverse sonogram of the thyroid, right lobe (R) displays normal, homogeneous echotexture without any nodule. Left lobe cannot be demonstrated. Strap muscles and vascular structures are displaced to fill the location of the left lobe (L).

Figure 2

Scintigraphic images of the neck obtained by parallel-hole collimator (a) and pinhole collimator (b). On anteroposterior views, right lobe of the thyroid gland (black arrows) shows minimal hyperplasia with homogeneous uptake. No nodule is demonstrated. At the location of the left lobe of thyroid gland and any other parts of the neck, no accumulation of radioactivity is obtained.