Visual acuity and functional measurements in the aging eye

Project Summary Age related macular degeneration remains the most common cause of permanent vision loss in the US and many industrialized countriesExtensive attention is paid to developing treatmentsresulting inregistered treatment trials in the USThe large numbers of patients and trials accentuates the need for improved biomarkers for the management of patientsFurtherif outcome measuresincluding visual acuitycould be made more accurate and have decreased test retest variabilitythen clinical trials could use smaller sample sizesThis leads to a savings in cost and time to bring therapies to marketWe will minimize the issues from the optics of the aging eye by building a Maxwellian view device with a low cost but high resolution display suitable for visual acuity testingSimultaneous retinal imaging and onboard focus will decrease the artifact from target defocus from retinal elevation due to exudative age related macular degenerationThe part of the retina that is used for visual acuity will be localizedRelated devices for microperimetry are more expensive and lack the resolution needed for visual acuityWe will use psychophysical techniques that are rapidaccurateand provide better measures of variabilityalternative forced choice with Method of Constant Stimuli and ZESTIn Aimwe will build a version of the digital light ophthalmoscopeDLOthat has a high resolution visual display and NIR illumination for retinal imagingThe imaging light is comfortable and dim enough not to interfere with visual tasksThe DLO projects a series of stripes onto the retina in a raster patternproviding line scanning for imagingtherefore increasing contrast even in the aging eye and exudationThe detection is via aD CMOS detector with a rolling shutterwith the serial read out of the lines either synchronized with the illumination or offset in timeThis provides a flexible electronic aperture under computer controlBoth confocal and multiply scattered light images are available during visual function testingrevealing drusen and other subretinal depositsor locations of sub retinal treatmentWe will optimize image quality and autofocus ability insubjects with a range of refractive errorocular pigmentationand ageIn Aimwe will optimize our novel method of visual acuity measurementTo model performance in aging eyes or those with macular degenerationwe will measure atand also degrade vision insubjects with Bangerter foils toandand compare to ETDRS chartsthen test with spatial pattern noise that masks the lettersIn Aimwe will develop new software that is robust in aging eyes to support a variety of visual function testscapable of focusing and registering visual targets to a specific location on the retinaWe will testnormal subjectsandpatients with age related macular degenerationThis project can move high quality visual testing into clinical trialsresearch facilitiesand eventually the lane Project Narrative Age related macular degeneration is the most common cause of vision loss in the USBoth the management of an individual patient and the cost and speed of clinical trials for new treatments can be improved by more accurate outcome measuresincluding the commonplace visual acuityWe propose to improve the measurement of visual function by reducing the influence of artifacts due to aging eyes and poor focus and localization of visual targets for eyes with exudative age related macular degeneration