Published online Apr 28, 2021. doi: 10.35711/aimi.v2.i2.32
Peer-review started: March 17, 2021
First decision: March 26, 2021
Revised: March 29, 2021
Accepted: April 20, 2021
Article in press: April 20, 2021
Published online: April 28, 2021
Processing time: 40 Days and 13.9 Hours
Intrathyroidal ectopic thymus (IET) is defined as an ectopic thymus tissue that is generally found incidentally and rarely in the thyroid gland in the pediatric group. It occurs as a result of disruption of the embryological migration path and the settling of the thymus tissue into the thyroid gland. In the differential diagnosis, it is mostly confused with thyroid nodules. Although thyroid nodules are less common in children than adults, the rate of malignancy is much higher. Therefore, knowing the general ultrasound findings of IET better may prevent unnecessary invasive attempts and surgical procedures. In this article, we tried to compile the key imaging findings of IET.
Core Tip: The unique ultrasonographic features of intrathyroidal ectopic thymus (IET) can be remembered as; well-circumscribed, hypoechoic eco pattern with linear or punctate echogenic foci resembling thymus, fusiform or oval shape, diameters smaller than 1 cm, location of middle and/or lower 1/3 part of thyroid gland, hypovascularity or avascularity and the same strain ratio values with the surrounding thyroid gland on elastography. Although some studies suggested cytopathological examination for the accurate diagnosis of a suspected IET case, majority of the previous studies stated that IET can be followed without the presence of any atypical findings. So that, unnecessary surgical or interventional procedures can be avoided.