# Synchrotron X-ray Radiation (SXR) in Medical Imaging: Current Status and Future Prospects
## 3 Synchrotron X-ray Radiation in Medical Imaging
### Breast Cancer  
Breast cancer patients' survival rate highly depends on its early diagnosis. Breast cancer was found to be the second most common type of cancer-based on its fatality rate. This rate is expected to drop from second to fourth, based on a projected decline in fatality rates in 2017 [31]. The main reason for this expected decline in fatalities among breast cancer sufferers is the huge investment over the years in research and development in diagnostic technologies specifically targeting breast cancer. Conventionally, traditional imaging modalities such as X-rays, magnetic resonance imaging (MRIs), and ultrasounds have been the standard diagnostic tools utilized in detecting breast cancer. These imaging technologies obtain such high resolutions that accurately localize the lesion inside the tissue. For instance, 3T MRI machines are capable of resolving details as small as 1 millimeter, and that resolution can be improved to 0.5 millimeters in a 7-T machine. Emerging optical imaging techniques such as diffuse optical imaging and photoacoustic are noninvasive medical imaging techniques capable of providing functional information of the tissue [32; 33]. However, the limited spatial resolution (around 1 cm) of these techniques is a challenge  
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**Reference** & **Type of Source and** & **Application** & **Further Information** \\ \hline [PERSON] et al. [28] & Synchrotron X-rays & Bone & Photon energies of 10–100 keV (comprising 64\% of the photons above 1 keV at _Ercit_ = 33 keV) \\ [PERSON] et al. [4] & Synchrotron radiation & Cardiovascular imaging & Crystal is placed 153 m from the source to produce a monochromatic beam, with energy selectable in the range 25–140 keV. A tungsten slit system, located approximately 150 m from the source, collimated the beam cross section to a size of 150 mm \(\times\) 6 mm; the photon energy for the experiments was 35 keV. \\ [PERSON] et al. [29] & Synchrotron radiation & Breast tomosynthesis & 150 mm \(\times\) 6 mm; the photon energy for the experiments was 35 keV. \\ [PERSON] et al. that usually is tackled by optical Imaging techniques with traditional X-rays, MRI, or ultrasound modalities [34,35]. New screening techniques which improve the sensitivity and specificity of current diagnostic modalities are needed to recognize women with early stage diseases. A recent study highlighted that propagation-based phase-contrast computed tomography (PB-CT) with synchrotron radiation (Australian Synchrotron (Clayton, Melbourne, Australia)) can provide significantly better breast cancer diagnosis accuracy with a similar level of exposure to the radiation [23]. A mastectomy sample from a 60-year-old woman was used for the investigation. The CT images along with the volume-rendered image are shown in Figure 5. The relative visual grading analysis (VGAS\({}_{\text{rel}}\)) of phase-contrast CT images was found to be 0.99 in this study indicating its higher quality than conventional absorption CT images. For breast cancer patients, different abnormal features of hair have been identified, such as the upgrowth of lipids and medulla loss of the patient hair are all potential biomarkers for screening of breast cancer. Hair samples from breast cancer patients were collected for determining diffraction patterns and results showed a new circular feature in a specific area of 4.6 angstroms. The observed samples were then identified ad positive and negative. The positive ones had a circular feature of 1.32 \(\pm\) 0.02. Synchrotron X-ray diffraction experiments were performed on the small-angle X-ray scattering--wide-angle X-ray scattering (SAXS-WAXS) beamline at the Australian Synchrotron, Melbourne. A MAR165 detector was used for the alignment of the sample and also for data collection. Diffraction patterns were analyzed using FIT2D and Saxs15 ID. Synchrotron X-ray sources at the Advanced Photon Source (Argonne National Laboratory) were used on two beamlines BioCAT and ChemMatCARS.