Virtual clinical trial platforms for digital breast tomosynthesis: a local solution compared to the VICTRE platform

Abstract

Aim: Compare an in-house developed hybrid simulation framework and the FDA’s total simulation framework VICTRE in an exercise to simulate realistic DBT images. Methods: Three different set-ups were investigated in increasing order of difficulty: (1) A simple object insert simulated in homogeneous backgrounds. (2) The same simple test object in a breast phantom to investigate the impact of a non-homogeneous background. (3) The simple test object replaced with clinically relevant lesions (spiculated and non-spiculated masses, calcification clusters) to test the frameworks in their entirety. Next to a visual analysis, a quantitative comparison based on contrast and signal-difference-to-noise (SDNR) measurements was performed. Results: Similar contrast and SDNR values in the ‘for processing’ images are obtained for a glandular test object when simulated with VICTRE and the Leuven platform, for both homogeneous as well as structured backgrounds (e.g. structured background; contrast: 0.13 and 0.12, SDNR: 8.99 and 8.56 for the Leuven platform and VICTRE respectively). The reconstruction algorithms of both frameworks differ, but the input of VICTRE images in an offline reconstruction tool like in the Leuven framework leads to similar results. In DBT reconstructed slices, the simulated mass models looked similar to the real lesions from which the model was derived. The simulated calcification clusters are more subtle when using the VICTRE framework, while all clusters appear to be realistic. This illustrates the need of full characterization of the methods. Conclusion: The step-by-step comparison of two very different frameworks was successful. Both frameworks are able to simulate objects with the same characteristics (contrast, SDNR, shape) and can create images with realistic lesions.