Conductive keratoplasty for presbyopia and two years follow-up

Abstract

To investigate the effect of conductive keratoplasty (CK) for presbyopia and 2 years follow-up. This study is prospective clinical trial. CK was performed on 34 patients for presbyopia, in which 26 hyperopic patients underwent binocular operations and 8 emmetropic patients underwent monocular operation. The following-up time was 24 months. At 24 months postoperatively, for the hyperopia group, binocular uncorrected near visual acuity (33 cm) (5-logMAR) (4.63 ± 0.12) was increased significantly (t = 9.237, P < 0.001) compared pre-operatively (4.06 ± 0.15); binocular uncorrected distance visual acuity (4.99 ± 0.02) was significantly increased (t = 6.718, P < 0.05) compared pre-operatively (4.82 ± 0.21); for the emmetropia group, binocular uncorrected near visual acuity (33 cm) (5-logMAR) (4.68 ± 0.16) was increased significantly (t = 10.413, P < 0.001) compared pre-operatively (4.13 ± 0.18); binocular uncorrected distance visual acuity was same as pre-operative one; compared pre-operatively (+0.97 ± 0.63D), manifest refractive spherical equivalent was decreased significantly (P < 0.001) to peak value (-1.21 ± 1.00) D at 1 week, and then regressed to a relative plateau (-0.40 ± 0.70) D at 24 months; the regressive rate was decreased from (+0.35 ± 0.44) D/month at 1 month postoperatively to (+0.01 ± 0.01) D/months at 24 months postoperatively. Contrast sensitivity and glare sensitivity, intraocular pressure, tear break-up time, endothelial cell count, central corneal thickness, stereopsis function and best corrected visual acuity were not significantly changed. For treatment of presbyopia, CK appeared to be safe, effective, refractive-predictable and controllable, and relatively stable at 24 months post-operatively. More long-time follow-up is necessary for further evaluation.