J Korean Ophthalmol Soc.  2019 Jan;60(1):9-15. 10.3341/jkos.2019.60.1.9.

The Effect of Preoperative Corneal Asphericity on the Refractive Outcomes of Multifocal Intraocular Lens Implantation

• Beak JU
• Shin HJ
• Park CH
• Whang WJ
• Na KS
• Kim HS

• KMID: 2431834
• DOI: http://doi.org/10.3341/jkos.2019.60.1.9

Abstract

PURPOSE
To analyze the effects of preoperative corneal asphericity on the refractive outcomes of multifocal intraocular lens implantation by correlating Q-values on anterior corneal surfaces and the prediction errors after surgery.
METHODS
Fifty-six eyes of 39 patients who underwent phacoemulsification, and multifocal intraocular lens implantation were included in this retrospective study. Intraocular lens power was calculated using the SRK/T, Hoffer Q, and Haigis formulas. The Q-values were measured at 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm with a rotating Sheimpflug camera (Pentacam®, Oculus, Wetzlar, Germany). The relationship between the prediction errors and the Q-values at 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm were assessed by linear regression.
RESULTS
Two different multifocal intraocular lens models (Acrysof IQ RESTOR +2.5D SV25T0 [Alcon Laboratories Inc., Fort Worth, TX, USA] and ZEISS AT LISA tri 839MP [Carl Zeiss Meditec AG, Inc., Jena, Germany]) were implanted in 56 eyes. In both groups, regression analyses showed statistically significant relationships between the prediction errors and the Q-values at 6 mm, 7 mm, and 8 mm using the SRK/T formula. The correlation coefficient between the Q-values and the prediction errors were higher using the SRK/T formula than using the Hoffer-Q and Haigis formulas.
CONCLUSIONS
Corneal asphericity affected refractive power during implantation of a multifocal intraocular lens and, as the preoperative Q-value increased, it resulted in a hyperopic refractive outcome for oblate corneas. These results were especially prominent when the SRK/T formula was used.

Keyword

Cataract; Cornea; Intraocular lenses; Refractive errors

MeSH Terms

Cataract
Cornea
Humans
Lens Implantation, Intraocular*
Lenses, Intraocular*
Linear Models
Phacoemulsification
Refractive Errors
Retrospective Studies

Figure

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  Figure 1 Scatter spot of axial length and the PE of the SRK/T formula. PE = prediction error; D = diopter.

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  Figure 2 Regression line showing the relationship between the PE of the SRK/T formula and corneal asphericity (Q-value 6 mm, 7 mm, 8 mm) in the (A) Acrysof group (left) and (B) ZEISS group (right). Straight line represent regression line, and two curved lines represent the 95% prediction interval. Scatter spot means patient distribution. PE = prediction error.

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