Ultrasound Imaging of Cervical Anatomic Variants

Abstract

: Embryologic developmental variants of the thyroid and parathyroid glands may cause cervical anomalies that are detectable in ultrasound examinations of the neck. For some of these developmental variants, molecular genetic factors have been identified. Ultrasound, as the first-line imaging procedure, has proven useful in detecting clinically relevant anatomic variants. The aim of this article was to systematically summarize the ultrasound characteristics of developmental variants of the thyroid and parathyroid glands as well as ectopic thymus and neck cysts. Quantitative measures were developed based on our own findings and the respective literature. Developmental anomalies frequently manifest as cysts that can be detected by cervical ultrasound examinations. Median neck cysts are the most common congenital cervical cystic lesions, with a reported prevalence of 7% in the general population. Besides cystic malformations, developmental anomalies may appear as ectopic or dystopic tissue. Ectopic thyroid tissue is observed in the midline of the neck in most patients and has a prevalence of 1/100,000 to 1/300,000. Lingual thyroid accounts for 90% of cases of ectopic thyroid tissue. Zuckerkandl tubercles (ZTs) have been detected in 55% of all thyroid lobes. Prominent ZTs are frequently observed in thyroid lobes affected by autoimmune thyroiditis compared with normal lobes or nodular lobes (P = 0.006). The correct interpretation of the ultrasound characteristics of these variants is essential to establish the clinical diagnosis. In the preoperative assessment, the identification of these cervical anomalies via ultrasound examination is indispensable.

What is this bump in my neck? Ultrasonographic evaluation of pediatric neck masses

“…Arrest of normal thymic migration causes ectopic thymic tissue along the route of descent that is usually asymptomatic and can be seen in up to 30% of autopsies On US, multiple homogeneously distributed punctate hyperechoic foci and linear septa give the characteristic “speckled appearance” of ectopic cervical thymus (Figure 10). 34 Cervical thymic cysts are rare and develop from degeneration of remnants of ectopic thymic tissue 9 . They usually present as a soft and painless neck masses but rarely, they may present with dyspnea, hoarseness, and dysphagia.…”

Extrathyreoidale Nebenbefunde bei der Schilddrüsensonografie

“…Eine vollständige Entfernung der Zystenstruktur mitsamt des Zungenbeinkörpers wird zur Rezidivprophylaxe empfohlen. Eine operative Entfernung ist auch im Hinblick auf die seltene Diagnose eines Malignoms im Bereich einer medianen Halszyste die Therapie der Wahl[25,26,27,28].…”