**1. Introduction**

Cataract surgery is the most common ocular surgery, with more than 20 million procedures performed worldwide [1]. Cataract surgery serves as both a visual restoration operation and refractive procedure [2]. Typically, the intraocular lens (IOL) is placed in a capsular bag. However, patients who experience posterior capsule rupture, zonular dialysis, dropped lens, or dislocated IOL during trauma or ocular surgery may receive alternative techniques such as anterior chamber, iris-fixated, or scleral-fixated IOLs [3].

The scleral-fixated IOL, first mentioned by Malbran [4] in 1986, has become a popular technique for patients with inadequate capsular support. The advantage of IOL scleral fixation over anterior chamber IOL implantation is the reduced risks of corneal endothelial loss, peripheral anterior synechiae, cystoid macular edema, and hyphema [5]. Although scleral-fixated IOL implantation has the problem of suture exposure, modified techniques can be applied to cover the suture ends with scleral pockets [6]. Another method is sutureless intrascleral-fixated IOL. A three-piece IOL is inserted into the anterior chamber, and

**Citation:** Chen, Y.-L.; Pu, C.; Lin, K.-K.; Lee, J.-S.; Liu, L.; Hou, C.-H. A Comparison of Visual Quality and Contrast Sensitivity between Patients with Scleral-Fixated and In-Bag Intraocular Lenses. *J. Clin. Med.* **2022**, *11*, 2917. https://doi.org/10.3390/ jcm11102917

Academic Editors: Nobuyuki Shoji and Laurent Kodjikian

Received: 17 March 2022 Accepted: 20 May 2022 Published: 22 May 2022

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**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

the haptics are pulled out and positioned in the scleral tunnels. However, the complication of this technique includes intraoperative haptic breakdown [3].

Visual acuity can be maintained or improved with scleral fixation [7], but visual quality with regards to higher-order aberrations (HOAs) and contrast sensitivity remain issues. The IOL tilt and decentration after scleral fixation are greater than those after in-bag implantation [8]. IOL decentration can lead to dysphotopsia [9], and IOL tilt induces a considerable amount of ocular coma-like aberrations [10,11]. The appropriate positioning of an IOL is crucial to satisfactory visual quality following cataract surgery. However, the literature on dysphotopsia and contrast sensitivity after scleral-fixated IOL surgery is scant.

The purpose of this study was to compare the visual acuity, aberrometry, and glare disability of eyes treated with scleral fixation with those of eyes treated with standard cataract surgery.
