J Korean Ophthalmol Soc.  2019 Feb;60(2):126-134. 10.3341/jkos.2019.60.2.126.

Accuracy of Astigmatic Correction Using Toric Intraocular Lens by Position and Size of Corneal Incision

• Park W
• Kim MS
• Kim EC

• KMID: 2438071
• DOI: http://doi.org/10.3341/jkos.2019.60.2.126

Abstract

PURPOSE
To assess the accuracy of toric intraocular lens (IOL) implantation by the location and size of the corneal incision.
METHODS
We retrospectively reviewed the medical records of 98 patients (98 eyes) who underwent phacoemulsification with toric IOL implantation from January 2014 to March 2017. The patients were divided into two groups: group 1 got an incision of the superior side of the cornea (n = 54) and group 2 received an incision on the temporal side of the eye (n = 44). For both groups, incisions were made at their steep corneal astigmatism axises. Each group was further divided into subgroups for whom different sized blades were employed (2.75 vs. 2.2 mm widths). We measured the refractive index and autokeratometric parameters. We postoperatively assessed residual astigmatism and any reduction thereof.
RESULTS
In both groups, uncorrected and best-corrected visual acuity, refraction cylinder astigmatism, and autokeratometric astigmatism improved statistically. Between two groups, corneal astigmatism decrease was not significant. Residual astigmatism also showed no significant differences between the two. Patients in both groups treated using 2.75 mm wide blades exhibited greater increases in corneal astigmatism.
CONCLUSIONS
During cataract surgery, precise correction of astigmatism via toric IOL implantation is possible when surgically induced astigmatism is minimized by careful choice of the location and size of the corneal incision.

Keyword

Astigmatism; Intraocular lens

MeSH Terms

Astigmatism
Cataract
Cornea
Humans
Lenses, Intraocular*
Medical Records
Phacoemulsification
Refractometry
Retrospective Studies
Visual Acuity

Figure

• 

  Figure 1 Double-angle plots of refraction cylinder astigmatism. Red dots are mean values of the amount and axis of refractive astigmatisms. (A) Group 1 (n = 52) preoperative (superior), postoperative (inferior). (B) In group 1, 2.75 mm incision subgroup (n = 39). (C) In group 1, 2.2 mm incision subgroup (n = 13). (D) Group 2 (n = 46). (E) In group 2, 2.75 mm incision subgroup (n = 35). (F) In group 2, 2.2 mm incision subgroup (n = 11). D = diopter.

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