All Publications

  • Comparison of confocal and non-confocal split-detection cone photoreceptor imaging Biomedical Optics Express Sredar, N., Razeen, M., Kowalski, B., Carroll, J., Dubra, A. 2021; 12 (2): 737–55


    Quadrant reflectance confocal and non-confocal scanning light ophthalmoscope images of the photoreceptor mosaic were recorded in a subject with congenital achromatopsia (ACHM) and a normal control. These images, captured with various circular and annular apertures, were used to calculate split-detection images, revealing two cone photoreceptor contrast mechanisms. The first contrast mechanism, maximal in the non-confocal 5.5-10 Airy disk diameter annular region, is unrelated to the cone reflectivity in confocal or flood illumination imaging. The second mechanism, maximal for confocal split-detection, is related to the cone reflectivity in confocal or flood illumination imaging that originates from the ellipsoid zone and/or inner-outer segment junction. Seeking to maximize image contrast, split-detection images were generated using various quadrant detector combinations, with opposite (diagonal) quadrant detectors producing the highest contrast. Split-detection generated with the addition of adjacent quadrant detector pairs, shows lower contrast, while azimuthal split-detection images, calculated from adjacent quadrant detectors, showed the lowest contrast. Finally, the integration of image pairs with orthogonal split directions was used to produce images in which the photoreceptor contrast does not change with direction.

    View details for DOI 10.1364/BOE.403907

    View details for PubMedCentralID PMC7901313

  • Dynamic distortion in resonant galvanometric optical scanners Optica Akondi, V., Kowalski, B., Burns, S. A., Dubra, A. 2020; 7 (11)

    View details for DOI 10.1364/OPTICA.405187

  • Novel microscopic foveal pit pathology in multiple sclerosis revealed with adaptive optics ophthalmoscopy Hargrave, A., Sredar, N., Razeen, M. M., Khushzad, F., Yarp, J., Leishangthem, L., Tomczak, A., Kipp, L., Han, M., Kowalski, B., Dubra, A., Moss, H. 2020: 5101–
  • Wavefront distortions in an oscillating resonant galvanometric optical scanner Computational Optical Sensing and Imaging Akondi, V., Kowalski, B., Sredar, N., Dubra, A. 2020: JW2A. 48
  • Non-confocal quad-detection adaptive optics scanning light ophthalmoscopy of the photoreceptor mosaic Sredar, N., Kowalski, B., Razeen, M. M., Steven, S., Dubra, A. 2018: 4632–32