Scaling law for noise variance and spatial resolution in differential phase contrast computed tomography.

PURPOSE The noise variance versus spatial resolution relationship in differential phase contrast (DPC) projection imaging and computed tomography (CT) are derived and compared to conventional absorption-based x-ray projection imaging and CT. METHODS The scaling law for DPC-CT is theoretically derived and subsequently validated with phantom results from an experimental Talbot-Lau interferometer system. RESULTS For the DPC imaging method, the noise variance in the differential projection images follows the same inverse-square law with spatial resolution as in conventional absorption-based x-ray imaging projections. However, both in theory and experimental results, in DPC-CT the noise variance scales with spatial resolution following an inverse linear relationship with fixed slice thickness. CONCLUSIONS The scaling law in DPC-CT implies a lesser noise, and therefore dose, penalty for moving to higher spatial resolutions when compared to conventional absorption-based CT in order to maintain the same contrast-to-noise ratio.

[1]  Franz Pfeiffer,et al.  Fabrication of diffraction gratings for hard X-ray phase contrast imaging , 2007 .

[2]  E L Nickoloff,et al.  A simplified approach for modulation transfer function determinations in computed tomography. , 1985, Medical physics.

[3]  Victor Arrizón,et al.  Binary phase grating for array generation at 1/16 of Talbot length , 1995 .

[4]  T J Suleski,et al.  Generation of Lohmann images from binary-phase Talbot array illuminators. , 1997, Applied optics.

[5]  Andrew G. Glen,et al.  APPL , 2001 .

[6]  M. Glas,et al.  Principles of Computerized Tomographic Imaging , 2000 .

[7]  Guang-Hong Chen,et al.  Quantitative imaging of electron density and effective atomic number using phase contrast CT. , 2010, Physics in medicine and biology.

[8]  Franz Pfeiffer,et al.  Quantitative phase-contrast tomography of a liquid phantom using a conventional x-ray tube source. , 2009, Optics express.

[9]  Guang-Hong Chen,et al.  Direct Fan-Beam Reconstruction Algorithm via Filtered Backprojection for Differential Phase-Contrast Computed Tomography , 2008 .

[10]  O. Bunk,et al.  Hard-X-ray dark-field imaging using a grating interferometer. , 2008, Nature materials.

[11]  Zhifeng Huang,et al.  Direct computed tomographic reconstruction for directional-derivative projections of computed tomography of diffraction enhanced imaging , 2006 .

[12]  O. Bunk,et al.  Hard x-ray phase tomography with low-brilliance sources. , 2007, Physical review letters.

[13]  R L Byer,et al.  Three-dimensional beam-deflection optical tomography of a supersonic jet. , 1988, Applied optics.

[14]  P. King.  Medical imaging systems , 1986, Proceedings of the IEEE.

[15]  O. Bunk,et al.  Neutron phase imaging and tomography. , 2006, Physical review letters.

[16]  Li Zhang,et al.  Alternative method for differential phase-contrast imaging with weakly coherent hard x rays , 2009 .

[17]  Guang-Hong Chen,et al.  Radiation dose efficiency comparison between differential phase contrast CT and conventional absorption CT. , 2010, Medical physics.

[18]  O. Bunk,et al.  Phase retrieval and differential phase-contrast imaging with low-brilliance X-ray sources , 2006 .

[19]  A. Rose,et al.  Vision: human and electronic , 1973 .

[20]  Oded Kafri,et al.  The physics of moire metrology , 1990 .

[21]  Atsushi Momose,et al.  Grating-Based X-ray Phase Imaging Using Multiline X-ray Source , 2009 .

[22]  Atsushi Momose,et al.  Demonstration of X-Ray Talbot Interferometry , 2003 .

[23]  Franz Pfeiffer,et al.  X-ray phase imaging with a grating interferometer. , 2005, Optics express.

[24]  Atsushi Momose,et al.  Efficiency of capturing a phase image using cone-beam x-ray Talbot interferometry. , 2008, Journal of the Optical Society of America. A, Optics, image science, and vision.