Abstract
Purpose: :
To determine whether Twinbel bevel toric (Sun Contact Lens Co. Ltd.), a newly designed rigid gas-permeable (RGP) contact lens with a toric bevel constitutedwith different radii of bevel curvature, improves visual function and complaint symptoms in patients with keratoconus.
Methods: :
We performed a retrospective analysis of a noncomparative case series of nine eyes of patients with keratoconus who had been wearing spherical, aspherical, or multicurve RGP contact lenses and who were fitted with Twinbel bevel toric at Yamaguchi University Hospital. Visual acuity and contrast sensitivity (at four spatial frequencies) were measured under photopic conditions. Complaint symptoms were recorded as primary outcome measures at follow-up visits.
Results: :
The mean best corrected visual acuity with Twinbel bevel toric was 0.89, which was significantly greater (P = 0.038, paired Student's t test) than that (0.58) achieved with the previously prescribed lens. Contrast sensitivity at spatial frequencies of 3, 6, 12, and 18 cycles/degree did not differ significantly between Twinbel bevel toric and the previous lens. Although subjective complaint scores did not differ, subjects reported an improvement in the feel of lens wear with Twinbel bevel toric compared with the previous lens. No serious complications of Twinbel bevel toric wear were observed.
Conclusions: :
Fitting of a Twinbel bevel toric lens improved visual acuity as well as the feel of lens wear in eyes affected by keratoconus. Twinbel bevel toric thus provides a viable alternative for management of such eyes.
Keywords: contact lens • keratoconus • visual acuity