Terahertz Pulsed Imaging of skin cancer in the time and frequency domain

Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge, CB3 OHE UK.
Journal of Biological Physics (Impact Factor: 1.15). 06/2003; 29(2-3):257-9. DOI: 10.1023/A:1024409329416
Source: PubMed

ABSTRACT Terahertz Pulsed Imaging(TPI) is a new medical imaging modality forthe detection of epithelial cancers. Overthe last two years this technique has beenapplied to the study of in vitrobasal cell carcinoma (BCC). Usingtime-domain analysis the contrast betweendiseased and normal tissue has been shownto be statistically significant, andregions of increased terahertz (THz)absorption correlated well with thelocation of the tumour sites in histology.Understanding the source of this contrastthrough frequency-domain analysis mayfacilitate the diagnosis of skin cancer andrelated skin conditions using TPI. Wepresent the first frequency-domain analysisof basal cell carcinoma in vitro,with the raw power spectrum giving aninsight into the surface features of theskin. Further data manipulation is requiredto determine whether spectral informationcan be extrapolated at depth. These resultshighlight the complexity of working inreflection geometry.

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Available from: Vincent Patrick Wallace, Aug 30, 2015
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    • "A great deal of attention has been paid to THz imaging system with biomedical applications due to the moderate wavelength of THz signal that can leverage advantages of both millimeter-wave (mm-wave) and optics, such as high spatial resolution, good penetration depth to dielectric material or human tissue with no harmful ionization [1]–[3]. Recently, remarkable contrast in skin and breast cancer has been demonstrated in THz images [4], [5]. Compared to the prevailing diagnostic methods such as confocal microscopy and optical coherence tomography (OCT), THz radiation shows much higher penetration depth (1–3 mm) into human skin, which can be leveraged into the diagnosis of cancer-related diseases. "
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    IEEE Transactions on Terahertz Science and Technology 11/2014; 4(6):686-695. DOI:10.1109/TTHZ.2014.2352040 · 4.34 Impact Factor
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    • "Recently, the possibility of THz applications has spread to various research fields and industries, e.g. medical diagnosis234567, drug inspection8, security applications9, chemical analysis1011, etc. In particular, THz technology is extremely important for wireless telecommunications12. Higher speed is critical for wireless communications and the THz frequency region is promising for this purpose. "
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    • "Recent progress in the development of broadband terahertz (THz) pulse sources based on ultrafast lasers1 has led to applications of THz pulses as a non-invasive tool in cancer diagnosis23456, intra-operative tumor margin identification7, assessment of burns8 and in vivo skin9 and cornea10 hydration sensing. At the same time, we are only starting to uncover how THz radiation, and especially intense THz pulses with duration on the order of 1 ps and peak electric fields on the order of 100 kV/cm and higher, interacts with biological tissue111213141516171819. "
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