title: Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland.
abstract: Radionuclide scintigraphy with I-131 and Tc-99m pertechnetate ((99)mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of I-131 and (99)mTc04 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland.
authors.affiliation: Department of Nuclear Medicine, Cardiology Institute, Istanbul University, Istanbul, Turkey.
authors.forename: Burcu Dirlik
authors.initials: BD
authors.lastname: Serim
authors.affiliation: Department of Nuclear Medicine, Corlu Public Hospital, Tekirdag, Turkey.
authors.forename: Ulku
authors.initials: U
authors.lastname: Korkmaz
authors.affiliation: Department of Nuclear Medicine, Haydarpasa Train and Research Hospital, Istanbul, Turkey.
authors.forename: Unal
authors.initials: U
authors.lastname: Can
authors.affiliation: Department of Nuclear Medicine, Medical Faculty, Trakya University, Edirne, Turkey.
authors.forename: Gulay Durmus
authors.initials: GD
authors.lastname: Altun
keywords: Hyperthyroidism; I-131; Tc-99m pertechnetate; intrathoracic goiter; toxic nodule