The Relationship between Long-Term Contact Lens Wear and Corneal Thickness

Purpose. The purpose of this study is to assess the effects of long-term contact lens wear on corneal thickness and to compare differences based on rigid versus soft lens material. Methods. This analysis included scanning slit topographic imaging (Orbscan, Bausch & Lomb, Rochester, NY) performed on 124 consecutive patients (248 eyes), who underwent comprehensive evaluations in consideration of refractive surgery by one surgeon. Results. Sixty-two 62 patients (124 eyes) who had not previously worn contact lenses had a least-squares mean pachymetry of 546.4 μm ± 3.5 SE. Thirty-nine patients (78 eyes) who had previously worn soft contact lenses for an average of 16 years had a least-squares mean pachymetry of 543.2 μm ± 3.8 SE. Twenty-three patients (46 eyes) who had worn rigid contact lenses for an average of 19 years had a least-squares mean pachymetry of 509.4 μm ± 6.9 SE. Mean pachymetry differed significantly between eyes wearing rigid lenses versus no lenses (P<0.0001) and between eyes wearing rigid lenses versus soft lenses (P=0.0002). Conclusion. Long-term rigid contact lens wear is associated with a decrease in the average central-corneal thickness (CCT) by an average of 37 μm, in this group of otherwise healthy eyes, compared to no contact lens wear. Long-term soft contact lens wear did not appear to significantly change corneal thickness compared to no contact lens wear, Caution should be exercised when screening patients with a history of long-term rigid contact lens wear for possible excimer-laser photoablative correction.