Advertisement

Abstract

The use of X-ray image receptors that produce a digital image is becoming increasingly important. Possible benefits include improved dynamic range and detective quantum efficiency, improved detectability for objects of low intrinsic contrast, and reduced radiation dose. The image can be available quickly. The display is separated from the image capture so that processing and contrast adjustment are possible before the image is viewed. The availability of a digital image means ready input into PACS and opens up the possibility of computer-aided detection and classification of abnormality. Possible drawbacks of digital systems include high cost, limited high contrast resolution and the fact that their clinical value is sometimes not proven in comparison with conventional, analogue techniques. The high contrast resolution attainable with such systems is discussed and the problem of sampling limitations and aliasing considered. The properties and limitations of digital systems using computed radiography, caesium iodide plus CCDs and active matrix arrays with either caesium iodide or selenium detectors are demonstrated. Examples are given of digital systems for mammography and general radiography and their performance is demonstrated in terms of clinical assessment and measurements of the modulation transfer function and detective quantum efficiency.

Keywords

Digital radiology mammography chest radiology 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Dobbins, J.T., 1995, Effects of under-sampling on the proper interpretation of modulation transfer function, noise power spectra and noise equivalent quanta of digital imaging systems, Med. Phys. 22 171-181CrossRefGoogle Scholar
  2. 2.
    Maidment, A.D.A., Fahrig, R., and Yaffe, M.J., 1993, Dynamic range requirements in digital mammography, Med. Phys. 20 1621-1633CrossRefGoogle Scholar
  3. 3.
    Cunningham, I.A., Westmore, M.S., and Fenster, A., 1994, A spatial-frequency dependent quantum accounting diagram and detective quantum efficiency model of signal and noise propagation in cascaded imaging systems, Med. Phys. 21 417-427CrossRefGoogle Scholar
  4. 4.
    Rowlands, J.A., 2002, The physics of computed radiography, Phys. Med. Biol. 47 R123-R166CrossRefADSGoogle Scholar
  5. 5.
    Yaffe, M.J. and Rowlands, J.A., 1997, X-ray detectors for digital radiography, Phys. Med. Biol. 42 1-39CrossRefGoogle Scholar
  6. 6.
    Hejazi, S. and Trauernicht, D.P, 1996, Potential image quality in scintillator CCD-based sys- tems for digital radiography and digital mammography, SPIE 2708 440-449CrossRefADSGoogle Scholar
  7. 7.
    Tesic, M.M., Fisher Piccaro, M., and Munder, B., 1999, Full field digital mammography scan- ner. Eur. J. Radiol. 31 2-17CrossRefGoogle Scholar
  8. 8.
    Pisano, E.D., Gatsonis, C., Hendrick, E., et al., 2005, Diagnostic performance of digital versus film mammography for breast-cancer screening, NEJM 353 1773-1783CrossRefGoogle Scholar
  9. 9.
    Samei, E. and Flynn, M.J., 2002, An experimental comparison of detector performance for computed radiography systems, Med. Phys. 29 447-459CrossRefGoogle Scholar
  10. 10.
    Samei, E. and Flynn, M.J., 2003, An experimental comparison of detector performance for direct and indirect digital radiography systems, Med. Phys. 30 608-622CrossRefGoogle Scholar
  11. 11.
    Kengyelics, S.M., Cowen, A.R., and Davies, A.G., 1999, Image quality evaluation of a direct digital radiography system in a UK radiology department, SPIE 3659 124-135ADSGoogle Scholar
  12. 12.
    Muller, S., 1999, Full-field digital mammography designed as a complete system, Eur. J. Radiol. 31 25-34CrossRefGoogle Scholar
  13. 13.
    Siebert, J.A., Filipow, L.J., and Andriole, K.R., (Eds) 1999, Practical Digital Imaging and PACS. AAPM monograph no 25. Medical Physics Publishing, Madison, WIGoogle Scholar
  14. 14.
    Vedantham, S., Karallas, A., Suryanarayanan, S., et al., 2000, Full breast digital mammography with an amorphous silicon-based flat panel detector: physical characteristics for a clinical prototype, Med. Phys. 27 558-567CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V 2008

Authors and Affiliations

  • David R. Dance
    • 1
  1. 1.Joint Dep. of PhysicsInstitute of Cancer Research and The Royal Marsden NHS Foundation TrustLondonUK

Personalised recommendations