RT Journal Article SR Electronic T1 Facial Anonymization and Privacy Concerns in Total-Body PET/CT JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1304 OP 1309 DO 10.2967/jnumed.122.265280 VO 64 IS 8 A1 Selfridge, Aaron R. A1 Spencer, Benjamin A. A1 Abdelhafez, Yasser G. A1 Nakagawa, Keisuke A1 Tupin, John D. A1 Badawi, Ramsey D. YR 2023 UL http://jnm.snmjournals.org/content/64/8/1304.abstract AB Total-body PET/CT images can be rendered to produce images of a subject’s face and body. In response to privacy and identifiability concerns when sharing data, we have developed and validated a workflow that obscures (defaces) a subject’s face in 3-dimensional volumetric data. Methods: To validate our method, we measured facial identifiability before and after defacing images from 30 healthy subjects who were imaged with both [18F]FDG PET and CT at either 3 or 6 time points. Briefly, facial embeddings were calculated using Google’s FaceNet, and an analysis of clustering was used to estimate identifiability. Results: Faces rendered from CT images were correctly matched to CT scans at other time points at a rate of 93%, which decreased to 6% after defacing. Faces rendered from PET images were correctly matched to PET images at other time points at a maximum rate of 64% and to CT images at a maximum rate of 50%, both of which decreased to 7% after defacing. We further demonstrated that defaced CT images can be used for attenuation correction during PET reconstruction, introducing a maximum bias of −3.3% in regions of the cerebral cortex nearest the face. Conclusion: We believe that the proposed method provides a baseline of anonymity and discretion when sharing image data online or between institutions and will help to facilitate collaboration and future regulatory compliance.