Date of Award
Master of Science in Vision Science
Aberration-reducing aspheric soft contact lenses are intended to provide enhanced visual performance, particularly for patients with small amounts of astigmatism. This study was designed to compare visual performance and patient preferences for aspheric soft contact lenses versus spherical soft contact lenses in low astigmats. The aims of the study were: (1) to determine if aspheric soft contact lenses offer better visual performance and patient satisfaction in comparison to standard spherical lenses and, (2) to determine if a difference in the type or magnitude of astigmatism affects the visual performance and patient satisfaction with both types of contact lenses.
Satisfaction ratings of overall vision was statistically better with the aspheric design (p=O.Ol). This was especially true for distance tasks including daytime driving and low light, nighttime driving. At the end of the study subjects preferred the Frequency 55 Aspheric lens with regard to vision (p=0.002), and overall. No matter what type of astigmatism, the final preference for the aspheric lens was significant and this was particularly evident for subjects manifesting oblique and against-the-rule cylinder. Objectively, there were no differences demonstrated in visual performance between the two lens designs.
Although a correlation was not observed between subjective preference and objective performance, clinically it is most often the patient's perception of the quality of their vision that ultimately determines the final lens choice. This study clearly demonstrates that even though differences in recorded visual acuity may not be observed during an eye examination, low astigmatic patients can perceive better vision with this aberration-reducing aspheric lens design in comparison to standard spherical soft contact lenses.
Wharton, Vandi; Wyckoff, Renee; and Knutson, Linda Tran, "The visual performance of the Cooper Vision Frequency 55 aspheric contact lens" (2003). College of Optometry. 1458.