Noninvasive visualization and analysis of parafoveal capillaries in humans.

Purpose: To demonstrate a noninvasive method to visualize and analyze the parafoveal capillary network in humans.

Methods: An adaptive optics scanning laser ophthalmoscope was used to acquire high resolution retinal videos on human subjects. Video processing tools that enhance motion contrast were developed and applied to the videos to generate montages of parafoveal retinal capillaries.

Pulsatility of parafoveal capillary leukocytes.

The use of adaptive optics (AO) in a confocal scanning laser ophthalmoscope (AOSLO) allows for long-term imaging of parafoveal capillary leukocyte movement and measurement of leukocyte velocity without contrast dyes. We applied the AOSLO to investigate the possible role of the cardiac cycle on capillary leukocyte velocity by directly measuring capillary leukocyte pulsatility. The parafoveal regions of 8 eight normal healthy subjects with clear ocular media were imaged with an AOSLO.

Direct and noninvasive assessment of parafoveal capillary leukocyte velocity.

Purpose: Alterations in leukocyte velocity have been implicated in many retinal disease processes. However, direct and objective assessment of leukocyte velocity in retinal capillaries has been limited by a reliance on invasive contrast dyes that allow leukocyte visualization only for a short time span. The recent application of adaptive optics in a scanning laser ophthalmoscope (AOSLO) has made long-term imaging of parafoveal leukocyte movement possible without contrast dyes.

Predicting and assessing visual performance with multizone bifocal contact lenses.

Purpose: To investigate how bifocal contact lenses, when combined with the aberrations of the eye, will affect visual performance. Also, to investigate the relationship between the patient's predicted and actual visual benefit with bifocal contact lenses.

Methods: The monochromatic aberrations of 16 subjects were measured and used to simulate visual quality with three bifocal contact lens designs.