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. 2016 Feb-Mar:9783:978303.
doi: 10.1117/12.2216260. Epub 2016 Mar 22.

Quantification of Resolution in Multiplanar Reconstructions for Digital Breast Tomosynthesis

Trevor L Vent  1 , Raymond J Acciavatti  1 , Young Joon Kwon  1 , Andrew D A Maidment  1
Affiliations

Quantification of Resolution in Multiplanar Reconstructions for Digital Breast Tomosynthesis

Trevor L Vent et al. Proc SPIE Int Soc Opt Eng. 2016 Feb-Mar.

Abstract

Multiplanar reconstruction (MPR) in digital breast tomosynthesis (DBT) allows tomographic images to be portrayed in various orientations. We have conducted research to determine the resolution of tomosynthesis MPR. We built a phantom that houses a star test pattern to measure resolution. This phantom provides three rotational degrees of freedom. The design consists of two hemispheres with longitudinal and latitudinal grooves that reference angular increments. When joined together, the hemispheres form a dome that sits inside a cylindrical encasement. The cylindrical encasement contains reference notches to match the longitudinal and latitudinal grooves that guide the phantom's rotations. With this design, any orientation of the star-pattern can be analyzed. Images of the star-pattern were acquired using a DBT mammography system at the Hospital of the University of Pennsylvania. Images taken were reconstructed and analyzed by two different methods. First, the maximum visible frequency (in line pairs per millimeter) of the star test pattern was measured. Then, the contrast was calculated at a fixed spatial frequency. These analyses confirm that resolution decreases with tilt relative to the breast support. They also confirm that resolution in tomosynthesis MPR is dependent on object orientation. Current results verify that the existence of super-resolution depends on the orientation of the frequency; the direction parallel to x-ray tube motion shows super-resolution. In conclusion, this study demonstrates that the direction of the spatial frequency relative to the motion of the x-ray tube is a determinant of resolution in MPR for DBT.

Keywords: Digital breast tomosynthesis (DBT); anisotropy; contrast; multiplanar reconstruction; phantom; super-resolution.

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Figures

Figure 1:
Figure 1:
Dome Phantom design. It consists of the (a) top hemisphere with star apex, (b) bottom hemisphere with apex and cylindrical cavity (shallow) that houses the test object, and (c) dome phantom in cylindrical encasement with the apex at the 0° dome rotation (top half of the cylindrical encasement is removed for clarity).
Figure 2:
Figure 2:
The dome phantom after it was 3D printed.
Figure 3:
Figure 3:
This figure shows the illustration of the dome orientation of 0°. (a) Shows the plane of the x-ray source, the apex, and the coordinate system. (b) Is an example of an oblique tilt at the dome orientation of 0°.
Figure 4:
Figure 4:
This figure shows the illustration of the dome orientation of 90°. (a) Shows the plane of the x-ray source, the apex, and the coordinate system. (b) Is an example of an oblique tilt at the dome orientation of 90°.
Figure 5:
Figure 5:
This figure shows the orientation of the MPR reconstructions. (a) The plane view of the star pattern at a 30° tilt. (b) Is a diagram comparing the MPR reconstruction slices to the conventional slices.
Figure 6:
Figure 6:
Example of the plot profile at the maximum visual spatial resolution.
Figure 7:
Figure 7:
This is an example of the plot profile at a low frequency.
Figure 8:
Figure 8:
Modulation contrast is calculated where the frequency meets the circumference of the circle on the star pattern.
Figure 9:
Figure 9:
Diagram and results for the dome 0° and phantom 0° orientation.
Figure 10:
Figure 10:
Limiting spatial resolution is shown in the images of the star pattern frequency for the phantom orientation of 0°
Figure 11:
Figure 11:
This figure shows the difference in quality between the central projection and the reconstruction.
Figure 12:
Figure 12:
Diagram and results for the dome 0° and phantom 90° orientation.
Figure 13:
Figure 13:
Diagram and results for the dome 90° and phantom 0° orientation.
Figure 14:
Figure 14:
Diagram and results for the dome 90° and phantom 90° orientation.
Figure 15:
Figure 15:
Example of the change in orientation for a phantom rotation of 45°.
Figure 16:
Figure 16:
Diagram and results for the dome 0° and phantom 45° and 135° orientations.
Figure 17:
Figure 17:
Diagram and results for the dome 90° and phantom 45° and 135° orientations.
Figure 18:
Figure 18:
The artifacts at a 0° tilt are more prominent than at a 30° tilt for a dome rotation of 0°.
See this image and copyright information in PMC

References

    1. Bartlett E et al. American Journal of Neuroradiology, vol. 27, pp. 13–19. (2006). - PMC - PubMed
    1. Acciavati R and Maidment ADA, "Oblique reconstructions in tomosynthesis. II. Super-resolution," Medical Physics, vol. 40, no 11, pp. 111912–1 to 111912–19 (2013). - PMC - PubMed
    1. Acciavatti RJ and Maidment ADA, "Oblique reconstructions in tomosynthesis. I. Linear systems theory," Medical Physics, vol. 40, no. 11, pp. 111911–1 to 111911–21 (2013). - PMC - PubMed
    1. Rasband WS, ImageJ, U. S. National Institutes of Health, Bethesda, Maryland, USA, http://imagej.nih.gov/ij/, (1997–2015).
    1. Acciavatti R and Maidment A, "Observation of super-resolution in digital breast tomosynthesis," Medical Physics, vol. 39, no. 12, pp. 7518–7539, (2012). - PMC - PubMed

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