Proposal of the Modified Radial Frequency Method Aimed for the Measuring Noise Property of the Digital Tomosynthesis Image

Abstract

The measurement method for the noise property of the digital tomosynthesis image has not been standardized in any guidelines or papers. Currently, a noise in a digital tomosynthesis image has been commonly measured using a 2-D fast Fourier transform（2D-FFT）method. The purpose of this paper is to propose a new method for measuring the noise property of a digital tomosynthesis image, which applies the radial frequency（Radial）method with a limited angular range （LAR）for data acquisition. Although the Radial method was used to obtain the power spectrum from all angles（360°）around the origin, the LAR method acquired the power spectrum in the limited angle regions. When the noise properties acquired by the LAR method with the limited angles of 3°, 5° and 15° were compared to those obtained through the Radial method and the 2D-FFT method. The results of the LAR method had the large differences compared to those of the Radial method in the u-axis direction. Further, the noise property of the LAR method and the 2D-FFT method showed a higher correlation in both axis directions. In conclusion, we believe that the noise properties of the digital tomosynthesis image can be measured by using the LAR method with a limited angle of 5°.