SONOGRAPHIC DEMONSTRATION OF A NORMAL THYROID-GLAND EXCLUDES ECTOPIC THYROID IN PATIENTS WITH THYROGLOSSAL DUCT CYST

OBJECTIVE. Preoperative thyroid scintigraphy has been performed in pat ients with presumed thyroglossal duct cyst to document a normal thyroi d and to exclude the possibility of an ectopic thyroid mimicking a thy roglossal duct cyst. Often, an ectopic thyroid is the patient's only f unctioning thyroid tissue, and its removal will result in hypothyroidi sm. The purpose of this study was to determine whether demonstration o f a normal thyroid gland by sonography in children with thyroglossal d uct cyst can exclude ectopic thyroid and thereby obviate routine preop erative thyroid scintigraphy. MATERIALS AND METHODS. We studied 30 pat ients with pathologically proved thyroglossal duct cysts who had neck sonograms, The sonograms were evaluated for the presence or absence of a normal thyroid gland, The medical records of these children were al so reviewed. Three children had normal preoperative radionuclide thyro id scans. Ail the children were clinically euthyroid preoperatively, F ollow-up was available in 15 of the 30 patients, and all of these pati ents were clinically euthyroid postoperatively. RESULTS. A sonographic ally normal thyroid gland was detected in ail patients. CONCLUSION. Pr eoperative sonographic identification of a normal thyroid gland in pat ients with thyroglossal duct cyst confirms a source of thyroid hormone separate from the thyroglossal duct cyst and thus excludes ectopic th yroid. Routine thyroid scintigraphy is not necessary.