Tolerance Of Residual Refraction After Implantation Of Enhanced Monofocal Intraocular Lens And Its Influence Due To Residual Cylinder

After implantation of enhanced monofocal intraocular lens (IOLs), tolerance of residual refraction, in which an acceptable uncorrected visual acuity (UDVA) is stably obtained, is anticipated. This retrospective study aimed to evaluate the tolerance of residual refractions in eyes with enhanced monofocal IOL with higher-order aspheric optics and investigate the influence of residual cylinder.

Tokyo Dental College Suidobashi Hospital 

Refractive records 1 month postoperatively of eyes with Eyhance IOLs   (Eyhance, J&J Surgical Vision) were investigated. Inclusion criteria were normal axial length, postoperative corrected distance visual acuity (CDVA) of 0.0 logMAR or better, and no complications. Refractive tolerances under three ranges of residual cylinders (zero, 0.0 to -1.0 D, and -1.0 D and less) were evaluated. Segmented regressions between spherical equivalent refraction (SE) and UDVA were analyzed, and tolerances from emmetropia to SE values for UDVA of 0.0 and 0.1 logMAR were evaluated.

280 eyes from 174 patients (mean age: 70.2 years) were eligible for analysis. For eyes with zero cylinder (N = 94), UDVA was stable until -0.60 D and regression results indicated that myopic tolerance for 0.0 and 0.1 logMAR would be -0.83 and -1.05 D, respectively. For eyes with cylinder of  0.0 to -1.0 D (N = 146), the myopic tolerances were obtained -0.6 and -1.0 D for 0.0 and 0.1 logMAR, respectively. In 40 eyes with cylinders of  -1.0 D and less, UDVA was relatively stable until -1.56 D and the myopic tolerances were -0.85 and -1.66 D.

In eyes with Eyhance IOLs, the refractive tolerance of -1.0 for UDVA of 0.1 logMAR was obtained with no residual cylinder. When the residual cylinder was -1.0 D or less, refractive tolerance was disturbed with wider tolerance for UDVA of 0.1 logMAR.