Abstract
With the increased use of neck ultrasonography (US), many different organ and tissue lesions have been detected. Most of these usually originate from the anterior neck organs such as the thyroid, parathyroids, lymph nodes, nerves, or esophagus. Among them, an esophageal diverticulum or paratracheal air cyst can demonstrate internal echogenic foci suggestive of air on US (1). There is little information regarding US images in patients having bowel structures in the anterior neck. We report the US findings in two such patients.
The first patient (Patient 1) was a 65-year-old woman who was seen for anterior neck pain. She had a history of an esophageal rupture during gastric endoscopy about 8 years ago. This was treated with esophageal reconstruction by gastric pull-up through the anterior mediastinum. The results of her thyroid function tests were normal. US showed a well-defined tubular hypoechoic mass with echogenic lining in the central portion of the lesion (Supplementary Fig. S1; Supplementary Data are available online at
The second patient (Patient 2) was a 68-year-old woman who was referred from a nearby clinic for evaluation of a thyroid nodule that was incidentally detected on US. Eleven years previously she had a colon interposition to replace resected esophageal cancer. The results of her thyroid function tests were normal. Neck US showed a well-defined tubular hypoechoic mass with echogenic lining in the central portion of the lesion (Supplementary Fig. S2). The patient had a chest CT scan for evaluation of a lung lesion showing high fluorodeoxyglucose (FDG) uptake on a previous PET scan, and interposed bowel with a metallic clip was seen in the lateral portion of the thyroid gland (Supplementary Fig. S2).
The normal bowel wall consists of five concentric layers having alternate echogenic and hypoechoic layers on US (2). The innermost layer is the superficial mucosal interface and is the first echogenic layer on US. The next layer is the muscularis mucosa and is the second hyperechoic layer on US. The next layer is the interface between the submucosa and the muscularis propria and is the third hyperechoic layer on US. The fourth layer is the muscularis propria and is the fourth hypoechoic layer. The final layer is serosa and is the fifth hyperechoic layer on US. Normal bowel has a wall thickness of 4 mm or less (3). In both of the patients reported here the bowel segments that were interposed in resected esophageal tissue demonstrated internal echogenic lines, which were due to intraluminal air that was noted on CT. This differs from the US finding of alternately echogenic and hypoechoic layers noted in normal bowel structures. Both patients reported here had US findings of a tubular hypoechoic mass with a central echogenic lining that was located at the anterolateral portion of the thyroid. CT showed metallic clips and they had surgical scars in their neck. These findings should alert the person performing US that unusual findings might be encountered, making it imperative that an accurate medical history be obtained.