Objective: To demonstrate optical coherence tomography for high-resolution, noninvasive imaging of the human retina. Optical coherence tomography is a new imaging technique analogous to ultrasound B scan that can provide cross-sectional images of the retina with micrometer-scale resolution. Design: Survey optical coherence tomographic examination of the retina, including the macula and optic nerve head in normal human subjects. Settings Research laboratory. Participants: Convenience sample of normal human subjects. Main Outcome Measures: Correlation of optical coherence retinal tomographs with known normal retinal anatomy. Results: Optical coherence tomographs can discriminate the cross-sectional morphologic features of the fovea and optic disc, the layered structure of the retina, and normal anatomic variations in retinal and retinal nerve fiber layer thicknesses with 10- μm depth resolution. Conclusion: Optical coherence tomography is a potentially useful technique for high depth resolution, cross-sectional examination of the fundus.

Optical Coherence Tomography of the Human Retina

An optical evaluation technique is described that is suitable for determining the positions and magnitudes of reflection sites within miniature optical assemblies. This method utilizes the coherence effects exhibited by a broadband optical source and is referred to as optical coherence-domain reflectometry. Background theory is given, and experimental results have demonstrated a resolution of 10 μm with an optical dynamic range of more than 100 dB.

Optical coherence-domain reflectometry: a new optical evaluation technique

Adlerʼs Physiology of the Eye

When optical coherence tomography (OCT) is used to image human retina, its lateral resolution is deteriorated by the
aberrations of the human eye. To get over this disadvantage, a high-resolution imaging system combining OCT with
adaptive optics (AO) is being developed. The AO system consists of a 61-element deformable mirror and a 16×16 array
Shack-Hartmann wave front sensor. In this paper, the configuration of the AO/OCT system is described, and the
simulation results and the static aberration analysis of AO/OCT systems are presented.

Adaptive optics optical coherence tomography

The higher-order aberrations of the human eye : connection with the pulse and effect on vision.

A high-resolution system for imaging the human retina in-vivo is presented. The imaging setup is a confocal microscope, which comprises the optics of the eye, coupled to an adaptive optics system which corrects for the dynamic aberrations of the eye to maximise the lateral and depth resolution. The need for high-resolution retinal imaging is discussed with particular reference to disease diagnosis and treatment. The thesis highlights some of the problems associated with retinal imaging and discusses confocal microscopy and adaptive optics as two techniques that can be combined to resolve some of these issues. The detailed presentation of these two techniques is followed by the description of the design process of the imaging system and the implementation of this design. A selection of the retinal images obtained is presented followed by an analysis in terms of lateral resolution, depth resolution and image contrast. The performance of the adaptive optics system is also assessed via the change in the point-spread function from the eye with adaptive correction. The thesis is concluded with a discussion of the current limitations of adaptive optics and retinal imaging and their prospects in ophthalmology.

Grupetta S

Papers

High-resolution retinal imaging using adaptive optics in a confocal laser scanning ophthalmoscope.