Accession Number : ADA294554

Title :   Early Detection of Breast Cancer and Recurrence Using Near Infrared Time Resolved Spectrophotometry.

Descriptive Note : Annual rept. 15 Mar 94-14 Mar 95,

Corporate Author : PENNSYLVANIA UNIV PHILADELPHIA

Personal Author(s) : Solin, Lawrence

PDF Url : ADA294554

Report Date : 13 APR 1995

Pagination or Media Count : 10

Abstract : The techniques are employed to measure the optical absorption and scattering factors of breast tissue. A pulse time device in which light at lower power (50 microW) laser diode is employed. The time delay in light propagation from the input to output fiber optic couplers is related to the scatting factor and the measured rate of decay of emerging photons is related to the absorption factor. Phase modulation, which is more convenient and rapid, measures the phase shift of a high frequency oscillating light of approximately the same power and wavelength used in the pulse nine method. Here, there is direct reading of the time delay which is characteristic of the scattering power when low frequency oscillation is employed. Contrast agents may be used to increase the tumor detection sensitivity. For example, the absorption of porphyrins at 620 nm and indocyanine green at 860 nm, afford possibilities to follow the time course of tumor uptake of optical contrast agents. Histopathological confirmation of diagnosis will be obtained and correlated with the optical and MRI results. Both the imaging and optical data obtained from this proposed project will facilitate research on using the optical properties of breast tissue to screen for early stage cancer. (AN)

Descriptors :   *NEAR INFRARED RADIATION, *PHASE MODULATION, *CANCER, *MAMMARY GLANDS, *INFRARED SPECTROPHOTOMETERS, FIBER OPTICS, TIME INTERVALS, LIGHT SCATTERING, CONTRAST, TISSUES(BIOLOGY), EXPERIMENTAL DATA, DETECTION, COMPARISON, SEMICONDUCTOR LASERS, OPTICAL DATA, OPTICAL IMAGES, SEMICONDUCTOR DIODES, PULSE GENERATORS, SENSITIVITY, DIAGNOSIS(MEDICINE), CASE STUDIES, RADIATION ABSORPTION, LIGHT TRANSMISSION, PHOTONS, SURGERY, TIME DOMAIN, PHASE SHIFT, WAVEGUIDE COUPLERS, PORPHYRINS.

Subject Categories : Medicine and Medical Research
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE