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Purpose: The purpose of this pilot study was to investigate the effect of different size pinholes on visual acuity (VA) at near (0.4 m) while various factors were altered. The alterations made involved accommodation and illumination. Method: Four subjects were selected and their ages ranged from 7 to 14 years. Subjective refractions were performed and then near visual acuities were measured at 0.4 m under two different lighting conditions (460 lux and 1 lux) by adding stigmatic (or spherical) lenses of positive and negative powers in front of pinholes of diameters 1.5 mm and 2 mm. Results: The results showed that there was an improvement in VA in most, however, the size of the pinhole played a minor role. Low illumination did have a drastic effect on our results not only by decreasing the amount of lenses used for near that gave more positive results, but also when the pinhole was placed in front of the subjects. According to Borish, the pinhole does improve VA by a straight forward process of elimination produced by spherical aberrations of the eye. However, this did not seem to be the case in this study under conditions of low illumination. Conclusion:The pinhole effect offers improvement in VA at near by reducing the amount of blur presented to the retina. This study showed that all subjects had an improvement in VA of at least two lines in high illumination. Pinhole size did not alter the results sufficiently thus suggesting that a pinhole, no matter the size, should increase the VA. However this was not the case when illumination was decreased.

A method of self-refraction, based on an old concept implemented with the aid of modern technology, is spectacles with adjustable lenses. The spectacle design is referred to as the Adspecs TM . The advantage of the Adspecs is that the wearer can adjust the powers of the lenses to suit his or her visual needs. The power is spherical and ranges from −6 to 6 D. Studies were undertaken in Ghana and South Africa. Subjects were instructed under supervision to adjust the powers of the Adspecs as accurately as possible to correct their vision and obtain the best visual acuity possible. An optometrist then refracted the patients and the results were then compared. For the right eyes, the mean stigmatic coefficient difference for distance vision was −0.13 D and the standard deviation 0.89 D. For the left eyes, the mean was −0.24 D and the standard deviation 0.91 D. For near vision, the mean for the right eyes was −0.27 D and standard deviation 1.07 D, and for the left eyes, the mean was −0.27 D and standard deviation 1.23 D. The standard deviations for the means (at distance and near) for left eyes were slightly greater than for the right eyes.

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