Characterization of lung tissues using liquid-crystal tunable filter and hyperspectral imaging system.

Hyperspectral imaging system has been developed to characterize lung tissue for detecting emphysematous tissues in lung volume reduction surgery. The system consists of a charge-coupled device and liquid crystal tunable filter, which is continuously tunable in the near-infrared spectral range of 650 - 1100 nm with a mean bandwidth of 5 nm. Using hyperspectral data, the spectral signature of healthy lung tissue and simulated smokers lung tissue is obtained and compared. The data show the peak absorption intensity at four different wavelengths (760, 805, 915, and 970 nm). However, the reflectance intensity of simulated smoker's lung tissue over all spectral range is considerably higher than the normal lung tissue. The differences provide the basis for the detection and characterization of emphysema from healthy lung tissue.