Primary posterior continuous curvilinear capsulorhexis combined with diffractive multifocal intraocular lens implantation

Abstract

PurposeTo evaluate the effect of mild posterior capsule opacity (PCO) on visual acuity (VA) in eyes implanted with a diffractive multifocal intraocular lens (IOL) compared with a monofocal IOL, and the effect of posterior continuous curvilinear capsulorhexis (PCCC) combined with diffractive multifocal IOL implantation.MethodsFor the initial evaluation, we compared charge-coupled device (CCD) camera photographs taken through both a monofocal IOL-loaded model eye and a diffractive IOL-loaded model eye under the conditions of both with and without an opaque filter for the simulation of mild PCO. The clinical evaluation involved 20 patients who underwent bilateral implantation of the same diffractive multifocal IOL. In all 20 cases, PCCC was performed in 1 eye (PCCC group) and not performed in the fellow eye (NCCC group). Postoperative clinical results were then compared between the two groups.ResultsThe CCD photographs revealed that the diffractive IOL-loaded eye was more strongly affected by the simulated PCO than was the monofocal IOL-loaded eye. In the clinical setting, the PCCC group registered better results than NCCC group in distance and near VA, low-contrast VA, and contrast sensitivity testing.ConclusionsDiffractive multifocal IOLs tend to be more influenced by mild PCO than do monofocal IOLs, and PCCC prior to IOL implantation can contribute to the avoidance of this effect.

Figure 1

Slit-lamp examination of a PCCC eye (right eye) at 1-day postoperative. (a) PCCC can be easily observed using retroillumination. (b) Macro photograph of the same eye illustrating the difference of transparency between the PCCC area and the remaining posterior capsule bordering the edge of the PCCC (arrowhead). PCCC, posterior continuous curvilinear capsulorhexis.

Figure 2

Comparison of images between through monofocal IOL and diffractive IOL loaded model eyes both with and without simulated mild PCO using an opaque filter. (a) Photograph taken through a monofocal IOL without simulated PCO. (b) Photograph taken through a diffractive IOL without simulated PCO. (c) Photograph taken through a monofocal IOL with simulated PCO. (d) Photograph taken through a diffractive IOL with simulated PCO. Without the opaque filter, the Landolt rings of the distance test chart (center) could be distinguished up to the five large rings, both in the monofocal IOL (a) and diffractive IOL (b) loaded model eye. With the opaque filter, contrast decreased in both of the IOL loaded model eyes. However, up to five large rings in the distance VA test chart could still be distinguished through the monofocal IOL loaded eye (c) whereas only three large rings could be distinguished and with strong degradation of image quality through the diffractive IOL loaded eye (d). Moreover, the 40 cm (left) and 50 cm (right) near VA test chart showed further image degradation through the diffractive IOL loaded eye (d). VA, visual acuity; diffractive, diffractive multifocal; IOL, intraocular lens; PCO, posterior capsule opacity.

Figure 3

Uncorrected (a) and best-corrected (b) postoperative distance VA. Uncorrected (c) and best-corrected (d) postoperative near VA.

Figure 4

Postoperative low-contrast VA. (a): 12.5% low-contrast VA, (b): 6% low-contrast VA.

Figure 5

Contrast sensitivity at (a) 1-day postoperative and (b) 6-months postoperative.