Retrospective analysis of vision correction and lens tolerance in keratoconus patients prescribed a contact lens with dual aspherical curves.
OBJECTIVE
To determine whether Aphex KC, a newly designed rigid gas-permeable (RGP) contact lens with dual aspherical base curves, improves visual acuity and lens wear time in patients with keratoconus.


METHODS
We performed a retrospective analysis of a noncomparative case series of 29 eyes of 24 patients with keratoconus who were intolerant of spherical RGP contact lenses and were fitted with Aphex KC at Yamaguchi University Hospital. Visual acuity and lens wear time were recorded as primary outcome measures at follow-up visits. Six patients with a follow-up period of <1 year were excluded from data analysis. At the last follow-up visit, 86.2% of eyes (25 eyes of 20 patients) continued to wear Aphex KC.


RESULTS
Mean uncorrected visual acuity was 1.4 LogMAR (20/500 in Snellen notation) for the 29 eyes enrolled in the study. Mean best-corrected visual acuity was 0.1 LogMAR (20/25) with Aphex KC and 0.7 LogMAR (20/111) with glasses (P < 0.001). A total of 19 eyes (65.5%) had a best-corrected visual acuity of 0.2 LogMAR (20/29) or better with Aphex KC. The mean +/- SD wear time was 12.6 +/- 3.2 hr/day with Aphex KC and 0.4 +/- 0.7 hr/day with a previously prescribed spherical RGP contact lens (P = 1 x 10). The numbers of eyes wearing Aphex KC or the previously prescribed RGP contact lens for >12 hr/day were 26 and 0, respectively (P = 1 x 10). No serious complications of Aphex KC wear were observed.


CONCLUSIONS
Fitting of an Aphex KC lens improved visual acuity and increased lens wear time in keratoconus patients who were intolerant of a spherical RGP contact lens. Aphex KC thus provides a viable alternative for management of such patients.
Yanai
Ryoji
R
Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube City, Yamaguchi, Japan. yanai@yamaguchi-u.ac.jp
Ueda
Kiichi
K
Nishida
Teruo
T
D000293:Adolescent; D000328:Adult; D003261:Contact Lenses / Q000009:adverse effects; D004867:Equipment Design; D005139:Eyeglasses; D005260:Female; D005500:Follow-Up Studies; D005740:Gases; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology* / Q000534:rehabilitation*; D008297:Male; D008875:Middle Aged; D010539:Permeability; D012189:Retrospective Studies; D013997:Time Factors; D014792:Visual Acuity; D055815:Young Adult
D005740:Gases