PT - JOURNAL ARTICLE AU - Betti, Francesca AU - Antonacci, Luca AU - Volterrani, Duccio TI - Artifact from <sup>131</sup>I contaminated mask in post-radioiodine therapy scintigraphy AID - 10.2967/jnmt.121.262438 DP - 2021 Jul 01 TA - Journal of Nuclear Medicine Technology PG - jnmt.121.262438 4099 - http://tech.snmjournals.org/content/early/2021/07/30/jnmt.121.262438.short 4100 - http://tech.snmjournals.org/content/early/2021/07/30/jnmt.121.262438.full AB - An occurrence of an artifact due to contamination is reported. A patient wearing the mandatory face mask because of the ongoing COVID-19 pandemic underwent post-radioiodine therapy scintigraphy. The spot view of the neck showed an area of intense iodine uptake with an unusual appearance. Suspecting a possible artifact due to iodine contamination, the patient was given a new mask to wear and the scan was repeated. Results. The subsequent images revealed that the previously detected hotspot was caused by mask contamination. Conclusions. This finding has led to updating the scan procedure for post-therapy scintigraphy by replacing the patients’ masks before the scan acquisition.