Radiologist evaluation of an X-ray tube-based diffraction-enhanced imaging prototype using full-thickness breast specimens.
OBJECTIVE
Conventional mammographic image contrast is derived from x-ray absorption, resulting in breast structure visualization due to density gradients that attenuate radiation without distinction between transmitted, scattered, or refracted x-rays. Diffraction-enhanced imaging (DEI) allows for increased contrast with decreased radiation dose compared to conventional mammographic imaging because of monochromatic x-rays, its unique refraction-based contrast mechanism, and excellent scatter rejection. However, a lingering drawback to the clinical translation of DEI has been the requirement for synchrotron radiation.


METHODS
The authors' laboratory developed a DEI prototype (DEI-PR) using a readily available tungsten x-ray tube source and traditional DEI crystal optics, providing soft tissue images at 60 keV. Images of full-thickness human breast tissue specimens were acquired on synchrotron-based DEI (DEI-SR), DEI-PR, and digital mammographic systems. A panel of expert radiologists evaluated lesion feature visibility and correlation with pathology after receiving training on the interpretation of refraction contrast mammographic images.


RESULTS
For mammographic features (mass, calcification), no significant differences were detected between the DEI-SR and DEI-PR systems. Benign lesions were perceived as better seen by radiologists using the DEI-SR system than the DEI-PR system at the [111] reflectivity, with generalizations limited by small sample size. No significant differences between DEI-SR and DEI-PR were detected for any other lesion type (atypical, cancer) at either crystal reflectivity.


CONCLUSIONS
Thus, except for benign lesion characterizations, the DEI-PR system's performance was roughly equivalent to that of the traditional DEI system, demonstrating a significant step toward clinical translation of this modality for breast cancer applications.
Faulconer
Laura
L
Department of Biomedical Engineering, University of North Carolina at Chapel Hill, CB #7000, 4030 Bondurant Hall, Chapel Hill, NC 27599, USA.
Parham
Chris
C
Connor
Dean M
DM
Zhong
Zhong
Z
Kim
Eunhee
E
Zeng
Donglin
D
Livasy
Chad
C
Cole
Elodia
E
Kuzmiak
Cherie
C
Koomen
Marcia
M
Pavic
Dag
D
Pisano
Etta
E
D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008327:Mammography / Q000295:instrumentation* / Q000379:methods*; D015588:Observer Variation; D010865:Pilot Projects; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014961:X-Ray Diffraction / Q000295:instrumentation* / Q000379:methods*