LEADER 00000nam  2200337   4500 
001    AAI3265165 
005    20081103095727.5 
008    081103s2007    ||||||||||||||||| ||eng d 
020    9780549024705 
035    (UMI)AAI3265165 
040    UMI|cUMI 
100 1  Desjardins, Adrien Emmanuel 
245 10 Angle-resolved optical coherence tomography 
300    149 p 
500    Source: Dissertation Abstracts International, Volume: 68-
       05, Section: B, page: 2893 
500    Advisers: Brett E. Bouma; Guillermo J. Tearney 
502    Thesis (Ph.D.)--Harvard University, 2007 
520    Optical coherence tomography (OCT) has emerged as a 
       powerful tool for probing the microstructure of biological
       tissue non-invasively at high-speed. OCT measures depth-
       resolved reflectance of infrared light, generating cross-
       sectional images non-invasively with micron-scale 
       resolution. As with other imaging modalities that employ 
       coherent detection, OCT images are confounded by speckle 
       noise. Speckle imposes a grainy texture on images that 
       reduces the signal-to-noise ratio to near unity values. As
       a result, it conceals subtle differences in scattering 
       properties known to be crucial for differentiating normal 
       from diseased tissue states. In this thesis, we developed 
       a novel OCT modality called "Angle-Resolved OCT" in which 
       depth scans (A-lines) are obtained simultaneously from a 
       broad range of backscattering angles. We demonstrated that
       high levels of speckle reduction can be achieved by 
       averaging the magnitudes of A-lines corresponding to the 
       same transverse locations. With both experimental and 
       analytic approaches, we demonstrated that this averaging 
       method does not lead to a substantial loss in spatial 
       resolution. We developed two different imaging systems for
       performing Angle-Resolved OCT. With the first system, 
       angular data was acquired simultaneously; with the second,
       it was acquired sequentially. The first system had 
       superior speckle-reduction capabilities but image quality 
       degraded significantly with small sample movements. The 
       second system allowed for in vivo imaging, as demonstrated
       with Resolved OCT systems, the speckle-reduced images 
       showed hitherto unprecedented delineation of tissue 
       microstructure 
590    School code: 0084 
590    DDC 
650  4 Physics, Optics 
650  4 Biophysics, Medical 
690    0752 
690    0760 
710 2  Harvard University 
773 0  |tDissertation Abstracts International|g68-05B 
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