PURPOSE: To assess corneal aberration changes induced by corneal refractive therapy (CRT) for different pupil sizes and to examine the recovery after cessation of contact lens wear. METHODS: A single-center, prospective, and longitudinal study was performed. Thirty-four subjects who underwent CRT for 1 year were included. High-contrast corrected distance visual acuity (CDVA), manifest refraction, and corneal topography were determined during the treatment and 1 month after the discontinuation of the treatment. Corneal aberrations were calculated using the Vol-CT 6.89 software. Corneal spherical aberration, Z(4,0), and root mean square values (RMS) for coma-like, trefoil, tetrafoil, and higher order aberrations (HOAs) were estimated for different pupil sizes (3-, 4-, 5-, 6-, and 7-mm diameters). Early Treatment Diabetic Retinopathy Study charts were used to measure CDVA. RESULTS: The CRT treatment induced a statistically significant increase of all aberrations studied for all pupil diameters. RMS values for coma-like, trefoil, and tetrafoil aberrations and HOAs after cessation of contact lens wear were not statistically significantly different for any of the different pupil diameters studied at baseline. However, Z(4,0) significantly increased from baseline to 1 month after discontinuation of the CRT lens wear for 5-, 6-, and 7-mm diameter pupils. CONCLUSIONS: Our results suggest that CRT is a treatment completely reversible at 1 month after cessation of contact lens wear in terms of CDVA, refractive error, and RMS of coma-like aberrations and HOAs for all pupil sizes. However, for spherical aberration, 1 month is not enough to recover to the baseline level.
PURPOSE: To assess corneal aberration changes induced by corneal refractive therapy (CRT) for different pupil sizes and to examine the recovery after cessation of contact lens wear. METHODS: A single-center, prospective, and longitudinal study was performed. Thirty-four subjects who underwent CRT for 1 year were included. High-contrast corrected distance visual acuity (CDVA), manifest refraction, and corneal topography were determined during the treatment and 1 month after the discontinuation of the treatment. Corneal aberrations were calculated using the Vol-CT 6.89 software. Corneal spherical aberration, Z(4,0), and root mean square values (RMS) for coma-like, trefoil, tetrafoil, and higher order aberrations (HOAs) were estimated for different pupil sizes (3-, 4-, 5-, 6-, and 7-mm diameters). Early Treatment Diabetic Retinopathy Study charts were used to measure CDVA. RESULTS: The CRT treatment induced a statistically significant increase of all aberrations studied for all pupil diameters. RMS values for coma-like, trefoil, and tetrafoil aberrations and HOAs after cessation of contact lens wear were not statistically significantly different for any of the different pupil diameters studied at baseline. However, Z(4,0) significantly increased from baseline to 1 month after discontinuation of the CRT lens wear for 5-, 6-, and 7-mm diameter pupils. CONCLUSIONS: Our results suggest that CRT is a treatment completely reversible at 1 month after cessation of contact lens wear in terms of CDVA, refractive error, and RMS of coma-like aberrations and HOAs for all pupil sizes. However, for spherical aberration, 1 month is not enough to recover to the baseline level.
Authors: Thao N Yeh; Harry M Green; Yixiu Zhou; Julie Pitts; Britney Kitamata-Wong; Sophia Lee; Shiyin L Wang; Meng C Lin Journal: Invest Ophthalmol Vis Sci Date: 2013-06-06 Impact factor: 4.799