Eye movements and reading with large print and optical magnifiers in macular disease

Abstract

Purpose: Reading rate has been the main performance measure in studies that have compared reading with large print and optical magnifiers; eye movement characteristics have not been considered. We compared both eye movement characteristics and reading rates for subjects with macular disease reading without and with a range of low-vision devices.
Methods: Silent reading rate and eye movement characteristics for text passages at critical print size of 21 subjects aged 14 to 88 years with macular disease were measured with and without their preferred low-vision device. Saccadic frequency was determined from a sequencing task comprising five letters each separated by 5 degrees. Eye movements were recorded using an infrared limbal reflection system.
Results: There were no significant differences in reading rate, fixation durations, saccade numbers per word, or percent retrace time when using a low-vision device compared with reading without a low-vision device. Saccadic frequency in the sequencing task was predictive of reading performance with and without a low-vision device.
Conclusion: When reading at critical print size, in terms of reading rate or saccades per word, there was no advantage to using large print over an optical low-vision device.