Predicting time to refractive stability after discontinuation of rigid contact lens wear before refractive surgery

Abstract

This was a retrospective study to determine the length of time required to reach refractive stability after discontinuation of rigid contact lens wear for purposes of preoperative evaluation for refractive surgery. Patients were examined at 3-week intervals after discontinuation of rigid contact lens wear, at which time visual acuity, subjective refraction, and corneal topography were performed. Stability was defined 2 consecutive examinations in which the refraction was within ± 0.25 diopter (D) sphere and 0.25 D cylinder with less than 25 degrees of axis orientation. Thirty-one (56.4%) of 55 eyes achieved stability by the second visit, suggesting that stability had been achieved within 3 weeks of discontinuation of lens wear. Twenty-four (43.6%) eyes required more than 2 visits to achieve stability, confirming instability still existed 3 weeks after discontinuation of lens wear. The number of years of contact lens was statistically significantly correlated with the likelihood of requiring longer time to reach refractive stability (P = .05). No statistically-significant between-group difference was observed in age, gender, refractive cylinder, topographic cylinder, difference between refractive and topographic cylinders, surface irregularity index, surface asymmetry index, or spherical equivalent at initial examination. The conclusion was that the length of time required to reach refractive stability after cessation of rigid contact lens wear is highly variable, especially for long-term wearers, and that the customary 3-week interval used by many refractive surgeons does not always allow sufficient time to obtain accurate preoperative measurements. —Michael D. Wagoner This was a retrospective study to determine the length of time required to reach refractive stability after discontinuation of rigid contact lens wear for purposes of preoperative evaluation for refractive surgery. Patients were examined at 3-week intervals after discontinuation of rigid contact lens wear, at which time visual acuity, subjective refraction, and corneal topography were performed. Stability was defined 2 consecutive examinations in which the refraction was within ± 0.25 diopter (D) sphere and 0.25 D cylinder with less than 25 degrees of axis orientation. Thirty-one (56.4%) of 55 eyes achieved stability by the second visit, suggesting that stability had been achieved within 3 weeks of discontinuation of lens wear. Twenty-four (43.6%) eyes required more than 2 visits to achieve stability, confirming instability still existed 3 weeks after discontinuation of lens wear. The number of years of contact lens was statistically significantly correlated with the likelihood of requiring longer time to reach refractive stability (P = .05). No statistically-significant between-group difference was observed in age, gender, refractive cylinder, topographic cylinder, difference between refractive and topographic cylinders, surface irregularity index, surface asymmetry index, or spherical equivalent at initial examination. The conclusion was that the length of time required to reach refractive stability after cessation of rigid contact lens wear is highly variable, especially for long-term wearers, and that the customary 3-week interval used by many refractive surgeons does not always allow sufficient time to obtain accurate preoperative measurements. —Michael D. Wagoner