Sarah Choi

Recent developments in adaptive optics - optical coherence tomography allow for ultra-high isotropic resolution imaging of the in-vivo retina, offering unprecedented insight into its volumetric microscopic and cellular structures. In addition to this promising achievement, the clinical impact and application of this technology still needs to be explored. This includes assessment of limitations and challenges for existing as well as future AO-OCT systems, especially in the context of potential transfer of this technology from an optical bench to a portable imaging system. To address these issues we will describe our current AO-UHR-OCT focusing on its sub-components, as well as application for clinical imaging. Additionally, we describe some directions for future development of our AO-OCT instrument that would improve its clinical utility including: new compact AO-OCT design, new improved AO sub-system, and new generations of Fourier-domain-OCT. © 2008 SPIE.

Purpose: To describe maculopathy diagnosed with high-resolution Fourier-domain optical coherence tomography among eyes with previously unexplained visual loss. Methods: Nine eyes from six patients with previously unexplained vision loss based on funduscopy, fluorescein angiography, and Stratus optical coherence tomography and 32 eyes from 25 asymptomatic age-matched control subjects were imaged with a Fourierdomain optical coherence tomography instrument with axial resolution of 4 mm to 4.5 mm and transverse resolution of 10 mm to 15 mm. Results: Among eyes with unexplained vision loss, visual acuity ranged from 20/20 to 20/80 and central scotoma was noted in all eyes by microperimetry or Amsler grid. Fourierdomain optical coherence tomography showed abnormality in the foveal photoreceptor layer in six eyes from four subjects. These abnormalities include focal loss of the PR layer with microcystoid changes in the macula, focal discontinuity of the PR layer, and focal elevation and blurring of the PR layer associated with a mild epiretinal membrane. Among age-matched control eyes, no foveal PR abnormality was seen. Conclusion: Fourier-domain optical coherence tomography detected subtle changes in the foveal PR layer in some eyes with vision loss and central scotoma unexplained with routine clinical diagnostic tests. © by Ophthalmic Communications Society, Inc.

Ultra-high isotropic resolution imaging of retinal structures was made possible with an adaptive optics system using dual deformable mirrors and a Fourier-domain optical coherence tomography system with correction for longitudinal chromatic aberration. This system was used to image microscopic retinal structures of healthy as well as diseased retinas in vivo. The improved resolution and contrast enhanced visualization of morphological structures in the retina can be clearly seen. The benefits of this instrument are apparent from comparison of new images with those acquired using a previous generation AO-OCT instrument. Big change in the appearance of speckle field can be observed as well. Additionally, further improvements in volumetric data acquisition and image representation will be discussed. This includes creation of large Field of View AO-OCT volume from multiple sub-volumes and its visualization. Also techniques and results of reducing speckle contrast by averaging multiple B-scans will be presented.