Date of Award
Master of Science in Vision Science
Background: It has been suggested that aspheric contact lenses may provide better visual performance than conventional spherical soft contact lenses. Previous studies conducted on Aspheric lenses found that they may be masking some astigmatism resulting in better vision. However, other studies have not supported this finding and instead found that Aspheric lenses may mask spherical aberration, providing better vision. In this study we compare the visual performance of two Aspheric lenses: Frequency 55 Aspheric and Biomedic Premium, to determine whether visual performance differs between them.
Methods: This study was a randomized, double blind in which the subjects wore two different aspheric lenses Cooper Vision Frequency 55 Aspheric and Biomedic Aspheric Premium for at least eight hours. We recruited seventeen optometry students from Pacific University who were current soft contact lens wearers. For both lenses, high and low contrast visual acuity were taken with their natural pupil size, subjective quality of vision was assessed with a questionnaire, and high contrast visual acuity was measured while the patient was dilated through a 3mm and a 6mm aperture to control pupil size.
Results: Objectively we found that there are no differences in visual performance between the two lenses. Subjectively, we found that patients preferred the vision of Biomedic Premium lenses over Frequency 55 Aspheric.
Conclusions: What ultimately will dictate which lens the patient will wear is based on patient comfort and fit. Based on our study Biomedics was subjectively preferred over the Frequency 55 Aspheric.
Leung, Lorina and So, Eva, "A comparative study on two aspheric lenses: Biomedic 55 aspheric and frequency 55 aspheric" (2007). College of Optometry. 1549.