Increased localization of 201 Tl-chloride in subacute thyroiditis.

We present two cases of subacute thyroiditis in which increased radionuclide activity in the affected areas was observed on 201 Tl thyroid scintigrams. These were taken to evaluate cold areas on the 99m Tc-pertechnetate thyroid scintigrams. This finding suggests that 201 Tl may be a potentially useful radionuclide in visualizing inflammatory lesions.