Demonstrable photopenic lesion in Tc-99m pertechnetate thyroid imaging after recent contrast radiographic procedure.
Iodine-contained contrast media of a recent arteriogram can block normal thyroid uptake of Tc-99m pertechnetate or radioiodine, resulting in virtual nonvisualization of the thyroid gland and showing a prominent salivary activity. In Tc-99m pertechnetate thyroid imaging, however, diffuse soft-tissue uptake in the anterior neck surrounding a fluid containing (cystic) lesion may standout as photopenia. The authors present two patients with recent contrast radiographic procedures who underwent Tc-99m pertechnetate imagings that demonstrated photopenic lesions: one was a thyroid cyst and the other confirmed an abscess.
Nuclear Medicine Service, Department of Veterans Affairs Medical Center, Lexington, Kentucky 40511.
W J
WJ
Shih
S
S
Magoun
B
B
Lahr
D000038:Abscess / Q000000981:diagnostic imaging*; D000368:Aged; D003287:Contrast Media; D003560:Cysts / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013670:Sodium Pertechnetate Tc 99m; D013959:Thyroid Diseases / Q000000981:diagnostic imaging*; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D013670:Sodium Pertechnetate Tc 99m