The effects of long term rigid gas permeable contact lens wear on ocular surface in keratoconus / 眼科

ABSTRACT

Objective To investigate the effects of rigid gas permeable contact lens (RGPCL) wearing 3 years on ocular surface in keratoconus.Design Retrospective case series.Participants 73 patients with keratoconus.Methods From July 2001 to July 2004,73 patients (142 eyes) wearing RGPCL for more than 3 years were collected in Peking University Optometry & Ophthalmology Center.Be- fore and at 1 year,2 years and 3 years of RGPCL wearing,density and morphologic changes of corneal endothelium were examined with non-contact specular microscope.Eye axial length,central and peripheral thickness of cornea were measured with A-scan pachymeter. All eyes were examined with slit-lamp microscope periodically.Main Outcome Measures Corneal endothelial density and morphology, corneal thickness,eye axial length,ocular surface changes.Results Before and at 1 year,2 years and 3 years of RGPCL wearing,aver- age corneal endothelial density was 2901.92?445.20,2862.78?497.13,2854.71?526.80,3015.61?421.22 (cells/mm~2)without significant difference statistically (F=1.571,P=0.20).Morphologic changes were not significant during 3 years.Eye axial length was 25.15?1.50, 24.93?1.36,24.78?1.25,25.39?1.31 (mm) without significant difference statistically (F=2.218,P=0.10).Corneal central thickness was 489.09?59.64,484.02?60.80,496.61?59.74,487.44?54.25(?m)without significant difference statistically (F=0.991,P=0.40).Peripheral thickness changes were also not significant statistically during 3 years.69 eyes with mild conjunctival congestion,12 eyes with corneal fluorescence stain and 6 eyes with corneal epithelial rough were found with slit-lamp microscope during follow-up.Conclusions For the patients with keratoconus,long term of RGPCL wear will not lead to significant ocular changes or severe ocular complications.