Abstract
Purpose: :
Fitting rigid gas permeable contact lenses (RGPCLs) for keratoconus patients is sometimes difficult because of uniquely protruded corneal shape and several patients require frequent prescriptions. The purpose of the current study is to investigate retrospectively frequencies and characteristics of renewing RGPCLs in keratoconus patients.
Methods: :
70 eyes of 43 keratoconus patients to whom renewal prescriptions of RGPCLs were made at the special contact lens clinic in the department of ophthalmology, the University of Tokyo hospital from June 2003 to November 2011 with at least more than 2 years follow-up were included in the current study. The age of the patients were ranged from 12 to 56 years old (average 29.5 ±9.8 years old). Follow-up periods, frequencies of renewing RGPCLs per a year, purposes of renewing RGPCLs were investigated.
Results: :
Mean follow-up periods were 50.5±15.9 months.(range 24-95 months) Mean frequencies of renewing RGPCLs per a year were 1.15 ± 0.68 times (range 0.35-3.00 times). Among total 255 times of renewing RGPCLs, the purposes were for changing base curves in 81 times (31.8%), lens power in 132 times (51.8%), lens sizes in 70 times (27.5%) and lens designs in 86 times (33.7%).
Conclusions: :
This retrospective data suggested average frequencies of renewing RGPCLs in keratoconus patients were more than once a year. More than half of the renewals of RGPCLs were related to lens power changes.
Keywords: keratoconus • contact lens