Proceedings Article | 2 March 2010
KEYWORDS: Prostate, Tissue optics, Optical properties, Optical coherence tomography, Scattering, Diffuse reflectance spectroscopy, Imaging systems, Absorption, Light scattering, Natural surfaces
Optical imaging systems utilizing near-infrared light sources such as optical coherence tomography (OCT) have
recently been used for imaging the prostate gland. However, the optimal wavelength for deep imaging of the
prostate has yet to be determined. The objective of this study is to determine the optimal near-infrared wavelength
for OCT imaging of the prostate using a system that has the potential to be used in an in vivo model. An obliqueincidence
single point measurement technique using a normal-detector scanning system was implemented to
determine the absorption (μa) and reduced scattering coefficients (μ's) of fresh canine prostate tissue, ex vivo, from
the diffuse reflectance profile of near-IR light as a function of source-detector distance. The effective attenuation
coefficient (μeff) and optical penetration depth (OPD) were then calculated for near-IR wavelengths of 1064, 1307,
and 1555 nm. A total of ten canine samples were used for this study. At wavelengths of 1064, 1307, and 1555 nm,
the mean absorption coefficients measured 0.08 ± 0.03, 0.12 ± 0.04, and 0.23 ± 0.09 cm-1, respectively. The mean
reduced scattering coefficients measured 16.60 ± 0.95, 14.30 ± 1.14, and 10.98 ± 2.35 cm-1. The effective
attenuation coefficients were calculated to be 2.00, 2.28, and 2.78 cm-1, yielding OPD's of 0.5, 0.44, and 0.36 cm at
1064, 1307, and 1555 nm. OCT imaging studies of the prostate may benefit from replacement of commonly used
1310 nm broadband light sources with 1064 nm sources.
