Ultrasound to CT Image-to-image Translation for Personalized Thyroid Screening

The use of 2D scintigraphy in the screening for thyroid pathologies is widespread, however its diagnostic value is limited because the activity of multiple thyroid lesions cannot be effectively resolved. Combining the scintigraphy with a CT would allow to simulate 3D SPECT and thereby increase the diagnostic value of the screening. However, during screening programs ultrasound is preferred to CT, because of its widespread availability and harmlessness. Therefore, tools to translate the thyroid ultrasound to CT are needed. In this perspective, we propose to translate ultrasound images of the thyroid into synthetic CT images using a GAN-based architecture. Our proposed approach results in a higher anatomical consistency between the input US and the output synthetic CT compared to the baseline. The synthetic CTs exhibit a realistic HU distribution compared to real CTs and maintain realistic appearance as indicated by the Fréchet Inception Distance.