Study details visual, refractive outcomes of opposite clear corneal incision combined with rotationally asymmetric multifocal intraocular lens implantation

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A team of researchers in China conducted a study to evaluate the visual and refractive outcomes of astigmatic cataract patients following treatment with an opposite clear corneal incision (OCCI) combined with rotationally asymmetric multifocal intraocular lens (IOL) implantation.

The researchers are from the Department of Ophthalmology, Zhongshan Hospital (Xiamen), Fudan University, Xiamen, China, and the Center for Evidence-based Medicine, Fudan University, Shanghai, China.

The retrospective cohort study included 58 cataract eyes of 54 patients with corneal astigmatism who underwent phacoemulsification and rotationally asymmetric multifocal IOL implantation, treated with either an OCCI (OCCI group) or a single clear corneal incision (SCCI group).¹

“In this study, we aim to investigate the efficacy and safety of the technique by comparing the visual and refractive outcomes of a group of cataract patients with or without an OCCI during phacoemulsification and rotationally asymmetric multifocal IOL implantation,” the researchers wrote.

Patients underwent phacoemulsification and rotationally asymmetric multifocal IOL implantation (Lentis Comfort LS-313 MF15, Teleon GmbH) from December 1, 2022, to April 30, 2023, at Zhongshan Hospital. The patients were 50 years or older with a preoperative magnitude of manifest astigmatism ≥ 0.5 diopter (D), and a preoperative magnitude of corneal astigmatism between 0.50 and 3.00 D.

In total, 58 eyes of 54 patients were enrolled in this study. These patients were separated into two groups based on whether they were treated with an OCCI or an SCCI surgical procedure.¹

An experienced surgeon performed all the surgeries, and proparacaine hydrochloride eye drops (Alcaine, Alcon) were administered to induce surface anesthesia. The surgical procedures differed between the 2 groups when performing corneal incisions.

In the OCCI group, limbal marks were made prior to surgery at the 3 and 9 o’clock positions on the cornea with patients sitting in front of the slit-lamp and looking straight ahead to avoid cyclotorsion. Patients underwent a topographic examination (Oculus 77000) before surgery, and the axis position of the maximal keratometry value from the axial map was selected as the main incision position.

In the SCCI group, limbal marks were not required. The incisions were made at the 11 and 1 o’clock positions (2.4 and 1 mm in width, respectively). The remaining surgical procedures were identical to those of the OCCI group, excluding the OCCI.¹

According to the researchers, the follow-up period was 3 months postoperatively. They accessed distance, intermediate and near visual acuity, refractive outcomes, and corneal anterior keratometry between the 2 groups, and a vector analysis was used to evaluate the astigmatism correction.

The researchers found that 3 months after surgery, the distance, intermediate, and near visual acuity, and sphere remained comparable between the 2 groups, but a significant difference was detected in residual astigmatism and anterior corneal keratometric astigmatism. In the OCCI group, the residual astigmatism and keratometric astigmatism were −0.60 ± 0.29 D and 0.59 ± 0.28 D, respectively, which were lower than those in the SCCI groups (−1.18 ± 0.47 D and 1.15 ± 0.45 D, both p < 0.05). In vector analysis, the difference vector, angle of error (AoE), absolute AoE, index of success, and correction index were statistically significantly different between the 2 groups (p < 0.05).¹

The researchers noted that the OCCI combined with rotationally asymmetric multifocal IOL implantation showed predictable and desirable efficacy in treating cataract patients with astigmatism.

“The current study confirms that incisions placed at the steep K meridian can safely reduce residual astigmatism after cataract surgery,” the researchers concluded in the study. “Corneal curvature optimized incision planning, specifically opposite the clear corneal incision, and combined with rotationally asymmetric multifocal IOL implantation provides optimal visual and refractive outcomes.”

The authors declare that financial support was received for the research, authorship, and/or publication of this article. This work was supported by Xiamen Municipal Natural Science Foundation (No. 3502Z20227277). It was also supported by the Science and Technology Project of Xiamen (No. 3502Z20224ZD1076). The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.¹

Reference:

1. Xiaoyo Qin, Pengxiang Yao, Xinyuan Wu, Yang Wu, Yufang Hong, Zhenzong Chen, Yuanzhi Yuan. Visual and refractive outcomes of opposite clear corneal incision combined with rotationally asymmetric multifocal intraocular lens implantation. Front. Med., Published June 27, 2024, Accessed June 28, 2024. Sec. Ophthalmology Volume 11 - 2024 | https://doi.org/10.3389/fmed.2024.1389186