Thyroglossal duct cysts: variability of sonographic findings.

Abstract

OBJECTIVE. The purpose of this study was to describe the sonographic features of thyroglossal duct cysts, emphasizing the variable sonographic appearances, and determine if the presence of infection or inflammation influences the sonographic appearance. MATERIALS AND METHODS. We reviewed the sonograms in 12 children (2 months-16 years old) with pathologically proven thyroglossal duct cysts (TDCs). The cysts were evaluated for location, size, cystic versus solid features, echogenicfty, and wall thickness. The sonographic features then were compared with the pathologic findings.RESULTS. Sonograms of the 12 lesions showed that nine were midline at or near hyold bone; two were to the right of midline in the submandibular region; and one was located to the left of midline in the neck. Cysts were from 0.5 cm to 4 cm in diameter. Five lesions were anechoic with no perceptible wall thickness. Seven lesions were hypoechoic.Two of the seven were homogeneously hypoechoic with thin borders. The remaining five lesions were hypoechoic but heterogeneous (complex). One lesion was hypoechoic with small anechoic spaces. Four lesions were largely cystic with dense internal echoes and thick walls. The presence of thick walls and internal echoes did not correlate with the presence or absence of inflammation on pathologic examination.No lesions in our series were hyperechoic. CONCLUSION.Our results indicate that TDCs have a variable sonographic appearance.Anechoic, homogeneously hypoechoic, and heterogeneous (complex) lesions occur. We found no correlation between the pathologic findings of infection and inflammation and the sonographic appearance of TDCs. Awareness of the variable sonographic appearance of the TDC is helpful when a midline lesion is encountered in the neck.

Sonographic Assessment of Thyroglossal Duct Cysts in Children

“…5,7,8 In our study, most of the lesions were unilocular, and only a small number were multilocular. We speculate that the difference of uniloculation or multiloculation is related to the embryologic process of the TDC.…”

“…In addition, in the same way, the location of the hyoid was characterized as suprahyoid, at the hyoid, or infrahyoid. The internal echo patterns were classified into 4 types according to 2 previous reports 7,8 : anechoic (strictly no internal echoes), homogeneously hypoechoic (lower amplitude than surrounding tissues, predominantly cystic with low-amplitude internal echoes), pseudosolid (more echogenic than the adjacent tissues), and heterogeneous. The wall thickness was defined as imperceptible, thin (1-2 mm), or thick (≥2 mm).…”

“…[3][4][5][6] However, both our findings and those of the 2 previous studies in children showed this "classic" appear- ance in less than half of all cases and suggested that most lesions had echogenicity ranging from hypoechoic to heterogeneous (Table 1). 7,8 Ahuja et al 8,25 found that the frequency of each internal echo pattern of TDCs was different between children and adults. Only a minority of cases in children are truly anechoic on sonography, and most have a pseudosolid appearance and a heterogeneous pattern.…”

“…[3][4][5][6] However, many variations of its sonographic features have been reported. 7,8 As a result, it is important to confirm the existence of a TDC in the differential diagnosis by means of preoperative sonographic examinations, but a correct diagnosis is often difficult to make. As far as we could determine, up to now there have only been 2 statistical investigations (by Wadsworth and Siegel 7 and Ahuja et al 8 surgically and pathologically proven TDCs.…”

A Rare Case of Squamous Cell Carcinoma in Thyroglossal Duct Cyst

“…The most helpful feature of these cystic neck masses in the differential diagnosis is the midline location, most often at or below the hyoid bone, and the relation of the cyst to the strap muscles. The sonography literature has emphasized the variable sonographic findings with an often-complex cystic appearance (8,9) . The CT findings of a TDC have also been well documented as a well-circumscribed, low-density lesion with a thin, smooth rim.…”