Related Experiment Video
Updated: Jun 10, 2025
Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography
Published on: August 11, 2016
Effect of prisms on visual acuity, contrast sensitivity and nystagmus in patients with albinism
Maryam Dashti1, Abbas Riazi2, Majid Ashrafi3
1Department of Optometry, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran 1616913111, Iran.
Aim:
To investigate the effect of using base-out prisms on nystagmus, visual acuity and contrast sensitivity in patients with albinism.
Methods:
In this interventional study, patients with albinism who had nystagmus were enrolled. A comprehensive eye exam was conducted, which included refraction, assessment of far and near vision acuity, and contrast sensitivity measurements. To check for the nystagmus, a videonystagmography was used. The tests were carried out in three modes: without any correction, with optical correction, and with correction using base-out prisms in three different powers, including 4, 6, and 8 prism diopters.
Results:
Totally 23 patients with average age of 28.65±12.13 were examined. It was found that the use of optical correction and optical correction with prisms resulted in a statistically significant improvement in both far (at least: P<0.006) and near visual acuity (at least: P<0.001 except for prism 8; P<0.02). In addition, contrast sensitivity significantly improved at all low and medium frequencies except for correction with prism 8 in frequency 1.5 (at least: P<0.01 except for prism 4, frequency 6; P=0.04). no significant improvement was observed in the evaluation of nystagmus characteristics.
Conclusion:
Optical correction with a prism can improve visual acuity and some spatial frequencies, but failed to improve nystagmus parameters.
