Goldstein Elianna,  White Elena,  Giamanco Nicole,  Rooks Veronica

Final Pr. ID: Poster #: CR-021

Langerhans cell histiocytosis (LCH) is a rare neoplastic disorder of abnormal proliferation of Langerhans cells affecting predominantly pediatric populations; sites of involvement include cutaneous, osseous, hematopoietic, and multisystem disease (1). Cutaneous involvement is common in children, though thymic involvement is rarely described (2). We report a case of an 8-month-old female infant with a dyad of cutaneous and thymic LCH. The purpose of this paper is to highlight a potentially underdiagnosed manifestation of infantile LCH and consider thymic sonography in infant LCH staging evaluation.

A one-month old female presented with skin lesions and pruritus suspicious for atopic dermatitis failing to respond to therapy. Punch biopsy demonstrated cutaneous LCH. Staging non-contrast chest computed tomography (CT) showed multiple very faint calcifications in the thymus (figure 1) which could have been obscured by intravenous contrast administration. Ultrasound demonstrated multiple echogenic foci in the thymus (figure 2). Pathology confirmed thymic LCH. Throughout her presentation, the patient’s clinical symptoms of LCH were limited to diffuse pruritic cutaneous lesions. Thymic involvement changed patient management to chemotherapy infusion. At the time of this report she has shown no signs of disease progression and she remains clinically stable. Read More

Authors:  Goldstein Elianna , White Elena , Giamanco Nicole , Rooks Veronica

Keywords:  Langerhans Cell Histiocytosis, Ultrasound, Thymus

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

Morris Melinda,  Lannigan Francis,  Thompson Andrew

Final Pr. ID: Poster #: EDU-008

The imaging characteristics of ectopic thymus will demonstrated on ultrasound and MRI. These imaging characteristics and the embryonal migration of the thymus will be illustrated with biopsied proven examples of ectopic thymus. Characteristic physical examination correlation is provided. The importance of confirming the precence or absence of thymus in the mediastinum is highlighted. A pictorial essay will be provided.
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Authors:  Morris Melinda , Lannigan Francis , Thompson Andrew

Keywords:  Thymus, Ectopic, Imaging

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

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