Pearson Richard,  Zbojniewicz Andrew,  Junewick Joseph

Final Pr. ID: Poster #: EDU-094

In pediatric radiology practices, we commonly encounter benign developmental aberrancies, such as urachal remnants, thyroglossal duct remnants, and branchial cleft anomalies. Understanding the embryological development and typical imaging appearances of these conditions streamlines the work-up and sometimes obviates surgical intervention. Although seen less commonly, this holds true for ectopic thymic tissue as well. In this presentation, we review the normal embryological development of the thymus with special attention to the course of the thymopharyngeal duct. We then review imaging cases resulting from aberrancies in this developmental process, such as an intra-thyroidal thymic rest, superior cervical extension of the thymus, and a thymopharyngeal duct cyst. In sharing these cases, we hope to improve familiarity with these benign developmental variants, and in doing so, to help optimize care for patients with these findings. Read More

Authors:  Pearson Richard , Zbojniewicz Andrew , Junewick Joseph

Keywords:  Thymus, Thymic Rest, Anomalies

Tamer Nicole,  Dahl Amy

Final Pr. ID: Poster #: CR-049

Ultrasound is the most commonly used modality in evaluating the thyroid gland and in classifying thyroid nodules. We present a three-case series of intrathyroidal ectopic thymus. Two of these cases were initially classified as high grade (TI-RADS 4) thyroid nodules and subsequently underwent fine needle aspiration (FNA). The third was recognized initially as intrathyroidal ectopic thymus, avoiding the need for FNA and followed conservatively. Ectopic thymic tissue can occur anywhere along the embryologic path of descent from the 3rd branchial pouch to the anterior mediastinum. Embryology of the thymus and common locations of ectopic thymic tissue will be reviewed. We will also review and illustrate ultrasound imaging characteristics of normal thymic tissue in the mediastinum as well as in ectopic locations, focusing primarily on the thyroid gland. We hope that the radiologist will consider the diagnosis of intrathyroidal ectopic thymus when evaluating thyroid nodules by ultrasound, differentiating them from other thyroid lesions and avoiding the need for FNA. Read More

Authors:  Tamer Nicole , Dahl Amy

Keywords:  Thymic Rest, Ultrasound, Thymus

Alazraki Adina,  Milla Sarah

Final Pr. ID: Poster #: CR-013

Ectopic thymic tissue may be found in the neck in up to 20% of the general population. Intrathyroidal thymic rest has been described as a rare entity, present in as many as 1% of children. The course of thymic migration parallels the thyroid and parathyroid glands, which explains their similar ectopic locations. While the natural history of these lesions has not been well studied, it is likely that there is involution of thymic rests with age. A few individual case reports have described the imaging features of intrathryoidal thymic rests confirmed by histopathology and flow cytometry. The aim of this case series is to raise awareness of the characteristic sonographic appearance of this entity to the radiology community. Read More

Authors:  Alazraki Adina , Milla Sarah

Keywords:  Thymic rest, TiRAD, Thyroid

Lai Lillian,  Halabi Safwan,  Yeom Kristen,  Barth Richard,  Seekins Jayne

Final Pr. ID: Poster #: EDU-078

The pediatric thymus is a constant but confusing, dynamic entity. The goal of this educational exhibit is to illustrate the range of appearances of the normal thymus and to identify key imaging features that can help pediatric radiologists differentiate normal thymic tissue from neoplastic conditions and other mimics. Read More

Authors:  Lai Lillian , Halabi Safwan , Yeom Kristen , Barth Richard , Seekins Jayne

Keywords:  thymus, ectopic, thymic, rebound, hyperplasia

Osman Radya,  Karmazyn Boaz

Final Pr. ID: Poster #: EDU-033

The Thymus appears in a variety of sizes and shapes, and may even change in size as a response to disease process in the same patient. These underlying variations, as well as ectopic or accessory tissue, can mimic pathology and may become a source of confusion resulting in anxiety, unwarranted imaging, unnecessary biopsy, chemoradiation or even surgery. Read More

Authors:  Osman Radya , Karmazyn Boaz

Keywords:  Thymus, Ectopic thymic tissue, Thymic pathology