Technical Note: Noise models for virtual clinical trials of digital breast tomosynthesis

Author(s)

Borges, Lucas R. ^{[1, 2]} ; Barufaldi, Bruno ^[3] ; Caron, Renato F. ^[4] ; Bakic, Predrag R. ^[3] ; Foi, Alessandro ^[2] ; Maidment, Andrew D. A. ^[3] ; Vieira, Marcelo A. C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Elect & Comp Engn, BR-13566590 Sao Carlos, SP - Brazil

^[2] Tampere Univ, Lab Signal Proc, Tampere 33720 - Finland

^[3] Univ Penn, Dept Radiol, Philadelphia, PA 19104 - USA

^[4] Pio XII Fdn, Barretos Canc Hosp, BR-14784400 Barretos, SP - Brazil

• Document type: Journal article
• Source: Medical Physics; v. 46, n. 6, p. 2683-2689, JUN 2019.
• Web of Science Citations: 0

Abstract

Purpose: To investigate the use of an affine-variance noise model, with correlated quantum noise and spatially dependent quantum gain, for the simulation of noise in virtual clinical trials (VCT) of digital breast tomosynthesis (DBT). Methods: Two distinct technologies were considered: an amorphous-selenium (a-Se) detector with direct conversion and a thallium-doped cesium iodide (CsI(Tl)) detector with indirect conversion. A VCT framework was used to generate noise-free projections of a uniform three-dimensional simulated phantom, whose geometry and absorption match those of a polymethyl methacrylate (PMMA) uniform physical phantom. The noise model was then used to generate noisy observations from the simulated noise-free data, while two clinically available DBT units were used to acquire projections of the PMMA physical phantom. Real and simulated projections were then compared using the signal-to-noise ratio (SNR) and normalized noise power spectrum (NNPS). Results: Simulated images reported errors smaller than 4.4% and 7.0% in terms of SNR and NNPS, respectively. These errors are within the expected variation between two clinical units of the same model. The errors increase to 65.8% if uncorrelated models are adopted for the simulation of systems featuring indirect detection. The assumption of spatially independent quantum gain generates errors of 11.2%. Conclusions: The investigated noise model can be used to accurately reproduce the noise found in clinical DBT. The assumption of uncorrelated noise may be adopted if the system features a direct detector with minimal pixel crosstalk. (c) 2019 American Association of Physicists in Medicine (AU)

• FAPESP's process: 16/25750-0 - Method for Simulating Dose Reduction in Digital Breast Tomosynthesis
• Grantee: Marcelo Andrade da Costa Vieira
• Support Opportunities: Regular Research Grants