الفهرس | Only 14 pages are availabe for public view |
Abstract Eccentric viewing (EV), also known as eccentric fixation, involves identifying an area of the retina that have reasonable sensitivity, and is as close to the fovea as possible in order to maximize details, and learn to use it effectively, which is known as preferred retinal locus (PRL). As in patients with a central scotoma from any macular disease, visual tasks are performed by directing the eye such that the image of the target of regard is placed within the preferred retinal locus (PRL). [6,7] In this study we monitored the direction of eccentric viewing (EV) in 33 low vision patients with bilateral central scotomas subjectively using Best Retinal Area (BRA) test. The preferred retinal locus (PRL) was identified using a direct ophthalmoscope, the preserved visual field was found using Octopus perimetry. The patients were divided randomly into two groups regarding their use of optical low vision devices with EV training. The patients and their guardians were educated regarding EV. After 2 months of weekly sessions and self-training at home, changes in near and far best corrected visual acuity (BCVA) and reading speed in words per minute were evaluated. After 2 months of EV training, near BCVA and mean reading speed significantly improved however, far BCVA did not significantly improve. Regarding the use of low vision devices, the group that used low vision devices with EV training (group 1) showed significant improvement in the near and far BCVA and in the reading speed than the group that did not use low vision device (group 2). So, we found that EV training can be used as a very effective method for low vision rehabilitation in patients presented with central scotomas and it can give very good results using simple and inexpensive equipment. The agreement between the subjective direction of EV, PRL location by the direct ophthalmoscope, and the visual field results in a more precise location of the PRL, so the patients can be educated for EV easily and gives better results after training. |