Nonvisualization of suppressed thyroid tissue on Tl-201 scintigraphy.
Tl-201 scintigraphy has been used to visualize thyroid tissue that is suppressed by an autonomously functioning thyroid nodule. Reports have indicated that the sensitivity of this technique rivals that obtained by I-123 scanning after thyroid-stimulating hormone stimulation. We report a case of triiodothyronine toxicosis caused by an autonomously functioning thyroid nodule in which the suppressed thyroid tissue was not visualized on Tl-201 scintigraphy. The suppressed tissue was readily identified with ultrasound imaging, which demonstrates the utility of this technique in differentiating between thyroid suppression and agenesis.
McEwan
J
J
Division of Nuclear Medicine, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107.
Park
C
C
D000328:Adult; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000150:complications / Q000000981:diagnostic imaging*; D013971:Thyrotoxicosis / Q000000981:diagnostic imaging* / Q000209:etiology; D014284:Triiodothyronine / Q000378:metabolism; D014463:Ultrasonography
D007457:Iodine Radioisotopes; D013794:Thallium Radioisotopes; D014284:Triiodothyronine