Ultrasonographic Features of the Major Salivary Glands after Radioactive Iodine Ablation in Patients with Papillary Thyroid Carcinoma

The aim of this study was to evaluate the ultrasonographic features of the major salivary glands (MSGs) after post-operative radioactive iodine ablation (RIA) in patients with papillary thyroid carcinoma (PTC). The study population comprised 202 consecutively registered PTC patients who had undergone total thyroidectomy, RIA and follow-up neck ultrasonography. The ultrasonographic features of the MSGs in each patient were retrospectively evaluated by a single radiologist, and the presence of post-RIA changes was determined by direct comparisons of pre- and post-RIA follow-up ultrasonographic scans. Of the 202 patients, 94 (46.5%) had post-RIA changes in the MSGs on follow-up ultrasonography. RIA dose was closely associated with the prevalence of post-RIA changes. Post-RIA changes were more common in the parotid glands (n = 93, 46.0%) than in the submandibular glands (n = 7, 3.5%). Common ultrasonographic findings representing post-RIA changes in MSGs included coarse echotexture, decreased echogenicity, lobulated margin and decreased gland size.