  The advent of computed tomography significantly improves patient health
regarding diagnosis, prognosis, and treatment planning and verification.
However, tomographic imaging escalates concomitant radiation doses to patients,
inducing potential secondary cancer. We demonstrate the feasibility of a
data-driven approach to synthesize volumetric images using patient surface
images, which can be obtained from a zero-dose surface imaging system. This
study includes 500 computed tomography (CT) image sets from 50 patients.
Compared to the ground truth CT, the synthetic images result in the evaluation
metric values of 26.9 Hounsfield units, 39.1dB, and 0.965 regarding the mean
absolute error, peak signal-to-noise ratio, and structural similarity index
measure. This approach provides a data integration solution that can
potentially enable real-time imaging, which is free of radiation-induced risk
and could be applied to image-guided medical procedures.
