Effect of Breast Compression on Lesion Characteristic Visibility with Diffraction-Enhanced Imaging

Received 7 July 2009; accepted 27 October 2009. published online 28 December 2009.

Rationale and Objectives

Conventional mammography can not distinguish between transmitted, scattered, or refracted x-rays, thus requiring breast compression to decrease tissue depth and separate overlapping structures. Diffraction-enhanced imaging (DEI) uses monochromatic x-rays and perfect crystal diffraction to generate images with contrast based on absorption, refraction, or scatter. Because DEI possesses inherently superior contrast mechanisms, the current study assesses the effect of breast compression on lesion characteristic visibility with DEI imaging of breast specimens.

Materials and Methods

Eleven breast tissue specimens, containing a total of 21 regions of interest, were imaged by DEI uncompressed, half-compressed, or fully compressed. A fully compressed DEI image was displayed on a soft-copy mammography review workstation, next to a DEI image acquired with reduced compression, maintaining all other imaging parameters. Five breast imaging radiologists scored image quality metrics considering known lesion pathology, ranking their findings on a 7-point Likert scale.

Results

When fully compressed DEI images were compared to those acquired with approximately a 25% difference in tissue thickness, there was no difference in scoring of lesion feature visibility. For fully compressed DEI images compared to those acquired with approximately a 50% difference in tissue thickness, across the five readers, there was a difference in scoring of lesion feature visibility. The scores for this difference in tissue thickness were significantly different at one rocking curve position and for benign lesion characterizations. These results should be verified in a larger study because when evaluating the radiologist scores overall, we detected a significant difference between the scores reported by the five radiologists.

Conclusions

Reducing the need for breast compression might increase patient comfort during mammography. Our results suggest that DEI may allow a reduction in compression without substantially compromising clinical image quality.

Key Words: Diffraction-enhanced imaging, breast cancer, breast compression, reader study, refraction contrast

a Department of Biomedical Engineering, University of North Carolina at Chapel Hill, CB#7000, 4030 Bondurant Hall, Chapel Hill, NC 27599

b Department of Radiology, University of North Carolina at Chapel Hill, CB#7000, 4030 Bondurant Hall, Chapel Hill, NC 27599

c Department of Pathology and Lab Medicine, University of North Carolina at Chapel Hill, CB#7000, 4030 Bondurant Hall, Chapel Hill, NC 27599

d Department of Biostatistics, University of North Carolina at Chapel Hill, CB#7000, 4030 Bondurant Hall, Chapel Hill, NC 27599

e Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, CB#7000, 4030 Bondurant Hall, Chapel Hill, NC 27599

f Department of Radiology, University of California at San Francisco, San Francisco, CA

g Brookhaven National Laboratory, National Synchrotron Light Source, Upton, NY

h Department of Radiology, Korea University, Seoul, Korea

Address correspondence to: E.D.P.

PII: S1076-6332(09)00592-3

doi:10.1016/j.acra.2009.10.020

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