Objectives: To compare the clinical performance of the Clearkone hybrid
contact lens for the treatment of keratoconus against the habitual contact
lens of the patients.
Methods: A total of 33 eyes from 18 patients were fitted with the
Clearkone. High- and low-contrast visual acuity (HCVA and LCVA),
central corneal thickness (CCT), and contrast sensitivity acuity (CSF) were
recorded with habitual lenses (prestudy visit) and after 1 week, 15 days, and
1 month of wear of prescribed Clearkone. Subjective vision and comfort
were rated using visual analogue scales (VAS).
Results: Three patients discontinued the study, one because of diffuse
corneal staining after 1 day of use and the other two because of extreme
discomfort. The rest of the patients completed the 1-month study. High
contrast visual acuity and LCVA (logMAR) improved significantly from
0.16 6 0.12 and 0.44 6 0.22, respectively, with the patient’s habitual contact
lenses to 20.006 6 0.058 and 0.23 6 0.13 after 1 day wearing Clearkone,
remaining significant during all follow-up visits (P,0.001; repeated measures
analysis of variance [RM-ANOVA]). There were no statistically significant
differences in the mean CCT. The improvement of CSF was statistically
significant with hybrid contact lenses prescribed compared with the patient’s
habitual contact lenses (P,0.001; RM-ANOVA test). Improvement in VAS
score, with prescribed Clearkone, was statistically significant for comfort
(P=0.043; RM-ANOVA test), but not for the subjective vision (P=0.759;
RM-ANOVA test).
Conclusions: Clearkone provides an improvement in visual acuity, contrast
sensitivity, and subjective comfort in patients with keratoconus when
compared with other contact lens options. However, clinicians must get
specific training to fit the lens and be aware of potential adverse event
