Time-resolved and continuous wave spectroscopic imaging of biological media.
Item
-
Title
-
Time-resolved and continuous wave spectroscopic imaging of biological media.
-
Identifier
-
AAI3283588
-
identifier
-
3283588
-
Creator
-
Al-Rubaiee, Mohammad.
-
Contributor
-
Advisers: R. R. Alfano | S. K. Gayen
-
Date
-
2007
-
Language
-
English
-
Publisher
-
City University of New York.
-
Subject
-
Physics, Optics | Physics, Radiation | Physics, Electricity and Magnetism
-
Abstract
-
Time-resolved and spectroscopic imaging approaches were developed and adapted and developed to detect and localize tumors in ex vivo breast tissue samples and tumorlike inhomogeneities breastlike phantoms. The experimental arrangement for time-sliced optical imaging used 120 fs, 1 kHz repetition-rate, 800 nm light pulses from a Ti:sapphire laser system for sample illumination and a 80 ps resolution ultrafast gated intensified camera system for recording 2-D time-sliced images. The spectroscopic imaging arrangement used 1225-1300 nm tunable output of a Cr: forsterite laser for sample illumination, a Fourier space gate to discriminate against multiple-scattered light and a near-infrared area camera to record 2-D images.;Results of these direct time-resolved imaging measurements on thin (5 mm--10 mm) breast tissue specimens revealed that early-light images highlight cancerous regions of the specimens, while late arriving light accentuates the normal fibroglandular tissues. These differences are attributed to the difference in light scattering characteristics of normal and cancerous tissues. In direct spectroscopic imaging measurements, when light was tuned closer to the 1203 nm absorption resonance of adipose tissues, a marked enhancement in contrast between the images of adipose and fibro-glandular tissues was observed. A similar wavelength-dependent difference between normal and cancerous tissues was observed. These results correlate well with pathology and nuclear magnetic resonance based analyses of the samples, and indicate the diagnostic potential of optical imaging approaches.;Detection and localization of targets in thick breast tissue specimens and phantoms was accomplished using independent component analysis (ICA) from information theory. The approach known as Optical Tomography using Independent Component Analysis (OPTICA) made use of multi-source probing of the samples, multi-detector transillumination signal acquisition, and analysis of resulting data using ICA for detection and three-dimensional localization of targets in turbid media. OPTICA was able to detect and determine the location of small scattering, absorptive, and fluorescence targets embedded in turbid media within a few millimeter in all three dimensions.
-
Type
-
dissertation
-
Source
-
PQT Legacy CUNY.xlsx
-
degree
-
Ph.D.
