Abstract
Radionuclide studies are indispensable for the management of thyroid diseases. Tc-99m pertechnetate is the most popular agent in the evaluation of goiter. The I-123 thyroid uptake measurement is recommended in some hyperthyroid states especially in the differential diagnosis between Graves' disease and chronic thyroiditis. Tl-201 chloride imaging is helpful in differentiating cystic lesions from solid tumors and depicting the metastatic and/or recurrent lesions of thyroid cancer. Ga-67 citrate is a useful agent to visualize anaplastic cancer and malignant lymphoma. Generally speaking, differentiation of benign nodules from malignancy and detection of small lesions less than 1cm in diameter are so difficult that sophisticated palpation, plane radiography and ultrasonography are required in addition to scintigraphy.
Internal irradiation with I-131 has been recommended as the most effective therapy for Graves' disease and metastatic thyroid cancer.
The enlarged parathyroid glands can be depicted by Tl-201 chloride imaging.
Salivary gland imaging with Tc-99m pertechnetate is useful in the evaluation of the Sjögren syndrome, and in the differentiation of Warthin's tumor and onchocytoma from the other tumors.
Ga-67 citrate imaging is useful in differentiating maxillary cancer from chronic sinusitis.
Bone scintigraphy can depict facial bone diseases and mastoiditis in their early stage.
Radionuclide andiography and brain scan reveal venous sinus thrombosis and acoustic neurinoma.
Radionuclide cisternography is helpful in detecting cerebrospinal fluid rhinorrhea.
Lung scintigraphy is useful in deciding which bronchus is obstructed with a foreign body.
Up-to-date studies of the cerebral blood flow and its metabolism with noninvasive techniques reveal functional locations of the brain receiving different stimulations, such as hearing, speaking, reading, etc.
