False positive finding on whole-body iodine-131 scan secondary to contaminated face mask: an uncommon peril in current COVID pandemic

Document Type : Case report

Authors

Department of Nuclear Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Abstract

Covid-19 has changed the practice of present-day medicine. Social-distancing, hand-sanitation and use of face-mask are important measures taken against its spread. Post-thyroidectomy whole-body diagnostic I-131 scan is an important preliminary investigation for risk stratification and further management in thyroid cancer. False positive findings on diagnostic scan are not uncommon and must be evaluated to avoid unnecessary work-up and treatment. Clinical and biochemical correlation with adjunct SPCET/CT imaging may differentiate true from false-positive lesions. We report a case of unusual false positive linear neck tracer on whole-body diagnostic I-131 scan due to the use of an I-131 contaminated face mask.

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