A semianalytic model to extract differential linear scattering coefficients of breast tissue from energy dispersive x‐ray diffraction measurements

Abstract

The goal of this work is to develop a technique to measure the x-ray diffraction signals of breast biopsy specimens. A biomedical x-ray diffraction technology capable of measuring such signals may prove to be of diagnostic use to the medical field. Energy dispersive x-ray diffraction measurements coupled with a semianalytical model were used to extract the differential linear scattering coefficients [mus(x)] of breast tissues on absolute scales. The coefficients describe the probabilities of scatter events occuring per unit length of tissue per unit solid angle of detection. They are a function of the momentum transfer argument, x=sin(theta/2)/X, where theta=scatter angle and lambda=incident wavelength. The technique was validated by using a 3 mm diameter 50 kV polychromatic x-ray beam incident on a 5 mm diameter 5 mm thick sample of water. Water was used because good x-ray diffraction data are available in the literature. The scatter profiles from 6 degrees to 15 degrees in increments of 1 degrees were measured with a 3 mm x 3 mm x 2 mm thick cadmium zinc telluride detector. A 2 mm diameter Pb aperture was placed on top of the detector. The target to detector distance was 29 cm and the duration of each measurement was 10 min. Ensemble averages of the results compare well with the gold standard data of A. H. Narten ["X-ray diffraction data on liquid water in the temperature range 4 degrees C-200 degrees C," ORNL Report No. 4578 (1970)]. An average 7.68% difference for which most of the discrepancies can be attributed to the background noise at low angles was obtained. The preliminary measurements of breast tissue are also encouraging.

Model predictions for the wide-angle x-ray scatter signals of healthy and malignant breast duct biopsies

“…In Fig. 3(a), both measured data by Kidane et al 41 and LeClair et al 37 matched well with the data calculated using Poletti et al 40 F and Hubbell et al 52 S values. Figure 3(b) shows data for fibroglandular tissue.…”

“…Although in previous work, 37,42,43 the symbol used for dμ s ∕dΩ was simply μ s , the new notation is more appropriate for denoting a differential linear scattering coefficient. At low x, it is F, which provides most contrast between tissue types but both types of scatter were included in this work.…”

Characterization of breast tissue using energy-dispersive X-ray diffraction computed tomography

“…Although several authors (Kidane et al, 1999;Castro et al, 2004;Geraki et al 2004;LeClair et al, 2006;Ryan and Farquharson, 2007;Oliveira et al, 2008) have proved that a different diffraction signal is achieved from normal and neoplastic breast tissue in the momentum transfer range 0.5 -4 nm -1 , there are few data about identification of different lesion types. In this study, the diffraction patterns of different lesions have been investigated using EDXRDCT.…”

“…Several studies, based both on the SAXS (Lewis et al, 2000;Fernandez et al, 2002;Round et al, 2005;Suhonen et al, 2005;Sidhu et al, 2009) and on the XRD modality (Kidane et al, 1999;Poletti et al, 2002;LeClair et al, 2006;Ryan and Farquharson, 2007;Oliveira et al, 2008), have shown the feasibility of breast tissue characterization. Of particular interest is the possibility of discriminating healthy and neoplastic tissue.…”

“…This was done using conventional diffractometers (Poletti et al, 2002;Oliveira et al, 2008), monochromatic synchrotron radiation (Castro et al 2004), or energy-dispersive systems (Kidane et al, 1999;Geraki et al, 2004, LeClair et al, 2006Ryan and Farquharson, 2007).…”