Efficacy of Toric intraocular lens implantation in eyes with high myopia: A prospective, case‑controlled observational study

Abstract

The present prospective clinical observational study aimed to evaluate the efficacy of Toric intraocular lenses (IOL) to achieve rotational stability and astigmatism correction in eyes with high myopia. A total of 27 consecutive cataract patients (39 eyes) with pre-existing corneal astigmatism (1.5–3.5 D) were divided into two groups according to their refractive status: One group of 18 eyes with high myopia -(12.5–6.0 D) and another group consisting of 21 eyes with emmetropia or low myopia (−3.0–0.0 D). All eyes underwent cataract phacoemulsification surgeries by the same surgeon, with the implantation of an AcrySof® Toric IOL at the pre-designed degree. Uncorrected visual acuity, best corrected visual acuity and phoropter examination results were recorded at the 1st day, 1st week, 1st month and 3rd month after the surgery. By analyzing digital images from slim-lamp photography with a self-designed software, the rotational stability was observed. The contrast sensitivity was also measured. No significant difference in the baseline and post-operative residual astigmatism was identified between the two groups (P>0.05). In addition, no significant difference in the degree of rotation was observed between the two groups. All patients had significantly improved visual quality after the surgery (P<0.05). In conclusion, the present study observed an equal astigmatism-correction efficiency and rotational stability in the two groups. A second auxiliary spot-penetrating incision, removal of visco-elastic substances and tight adherence of the IOL to the posterior capsular membrane are essential for a successful surgery.

Anterior capsule coverage and rotational stability of an acrylic toric intraocular lens

“…Some previous studies reported that long axial length is a risk factor for toric IOL rotation, whereas others denied the association between long axial length (high myopia) and toric IOL rotation. [1][2][3][4][5][6][7][8][9] These conflicting findings might be attributable to the difference in IOL diameter (12.0 to 13.5 mm), surface finishing of the IOL (frosted or not), and different timing to measure the reference axis. 9 Toric IOLs form different manufacturers behave differently depending on the material, design, mechanical stability, and surface finish, leading to dissimilar surgical outcomes in rotational stability, amount of residual astigmatism, and incidence of repositioning surgery.…”

“…Although some studies reported that long axial length is a risk factor for toric IOL rotation, others denied the association between long axial length (high myopia) and toric IOL rotation. [1][2][3][4][5][6][7][8][9] Aspiration of residual lens epithelial cells was found to make no difference in toric IOL rotation, but another study suggested that reducing the polishing of anterior capsule might improve the rotational stability of a toric IOL. 2,6 There was 1 study that indicated significant correlation between the area of capsulorhexis and postoperative rotational stability, whereas another study reported no correlation between IOL rotation and capsular contraction.…”

Evaluation of preoperative corneal astigmatism using swept-source optical biometry in Chinese cataract surgery candidates with high myopia: a prospective, comparative observational study

“…In current clinical practice, corneal astigmatism correction during cataract surgery has been identified as an important factor in improving postoperative vision (11). Although limbal relaxing incisions, excimer lasers, femtosecond lasers and other similar procedures could address corneal astigmatism at the time of cataract surgery, toric IOLs are still the preferred approach to correct astigmatism (11,29); they have been shown to be safe and efficacious in highly myopic eyes (9,30), and increasing numbers of surgeons are practising this approach. Because patients with high myopia tend to suffer cataracts at a younger age than those without high myopia and have a high incidence of anxiety and depression (>20%), high myopia patients have higher expectations for postoperative visual function (1,31,32).…”

“…Due to advances in phacoemulsification techniques, intraocular lens (IOL) power calculations and IOL design, cataract surgery is routinely performed in patients with high myopia (6,8). In particular, those who suffer from both cataracts and corneal astigmatism can now undergo implantation of a toric IOL, which corrects corneal astigmatism to improve postoperative visual acuity and increase spectacle independence (9)(10)(11). Findings in several studies (11)(12)(13)(14) have suggested that corneal astigmatism is a major contributor to uncorrected poor vision after cataract surgery and that correcting residual astigmatism can greatly improve visual acuity both at a distance and up close.…”

Stereopsis after bilateral implantation of Toric intraocular lenses in high myopic cataract patients with astigmatism

“… 4 Although a long axial length is a risk factor for Toric IOL rotation, emerging studies have indicated high predictability and reliability of Toric IOL in correcting astigmatism compared to limbal relaxing incisions, and no significant difference in the rotation degree was noted between high myopia and low myopia. 5 , 6 , 7 , 8 …”