Polarimetric high-resolution confocal scanning laser ophthalmoscope

Laboratorio de Optica, Departamento de Física, Universidad de Murcia, Campus de Espinardo (Edificio C), Spain.
Vision Research (Impact Factor: 1.82). 01/2006; 45(28):3526-34. DOI: 10.1016/j.visres.2005.08.008
Source: PubMed


A polarimetric high-resolution confocal scanning laser ophthalmoscope has been developed. The system incorporates a fixed linear polarizer in the illumination path and a rotatory quarter-wave plate and another fixed linear polarizer in the registration path. Retinal areas that are smaller than those provided by commercial instruments can be imaged. Series of four fundus images for independent polarization states in the second pass were recorded for different eyes and retinal locations and the spatially resolved Stokes vectors calculated. From those images, the contrast across retinal blood vessels was maximized and the corresponding image was reconstructed. In terms of polarization, the analysis of small retinal areas might prove to be useful in the improvement of retinal imaging and the enhancement of structural details in the early diagnosis of ocular pathologies.

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Available from: Juan M Bueno
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    • "The DOP values shown in this work ranged between 0.10 and 0.82. These are similar to those values reported for other retinal areas (Bueno and Vohnsen, 2005) and they lie in the upper range of the values reported by Naoun et al. (2005). Most participants involved in the present study were younger than those involved in Naoun et al.Õs experiment. "
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    • "The statistics of the SH photon count gives additional insight and may be of value for posterior image processing. It is possible to quantify the image contrast in terms of a global root-mean-square (RMS) contrast for each image (Bueno & Vohnsen, 2005). All images (Fig. 5 "
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