Upon the application of reading glasses most patients achieved a near visual acuity of 20/25 or better (p<0.001). The average uncorrected near visual acuity was 20/50. Data was collected from a subset of patients who voluntarily participated in a pilot survey of the perceived barriers and benefits of correcting presbyopia. Patients age ≥40, without anatomical visual impairment or blindness, were invited to undergo near visual acuity testing and be fitted with reading glasses. conduct a survey of the perceived barriers and benefits of its treatment. The present project was undertaken to treat presbyopia in a rural Filipino population and. Treating presbyopia is simple however, many rural communities lack basic eye care. Sufficient near visual acuity is required for many activities of daily living. Presbyopia is the diminished capability of the eye to focus on near objects, which begins between the ages of 40-50 and accelerates with age. These results demonstrate that the depth illusion obtained from contrast of colour implicates similar cortical areas as classic binocular depth perception. The component was larger over the right hemisphere consistent with RH dominance in depth processing, likely due to context-dependent top-down modulation. VEP amplitude but not latency effects were observed to colour depth cues, suggesting an underlying, depth-specific slow negative wave, located using source modelling first in occipito-parietal, parietal, then temporal areas. Chromostereopsis was found with the stimuli combining spectra extremes.
To determine the cortical processing of this colour-based depth effect, visual evoked potentials (VEPs) to contrasts of colour were recorded in 25 subjects. Whereas this phenomenon is widely documented from the optical and psychophysical point of view, its neural correlates have not been investigated. Chromostereopsis is an illusion of depth arising from colour contrast: ocular chromatic aberrations usually make red appear closer to the viewer than blue.
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