Cataract Surgery in Eyes with Low Corneal Astigmatism: Implantation of the Acrysof IQ Toric SN6AT2 Intraocular Lens

One-dioptre toric IOL versus spherical IOL in eyes with low preoperative corneal astigmatism

Purpose

To investigate the advantages/disadvantages of a 1.0 D toric IOL vs spherical IOL after regular phacoemulsification in eyes with preoperative astigmatism ≤ 1 D.

Methods

Retrospective comparative series involving pseudophakic eyes with preoperative topographic astigmatism ≤ 1.0 D implanted either with monofocal 1.0 D Toric IOL (T-group), or with spherical IOL (S-group). The postoperative refractive astigmatism (PRA, i.e. surgically induced + corneal) was the main outcome; also considered in the analyses were the uncorrected and best-corrected distance visual acuity (VA). The data were referred to the last postoperative follow-up visit, 2 to 4 months after surgery.

Results

A total of 60 eyes were included: 30 in the T-group and 30 in the S-group, matched for patient’s age, laterality, and axial length. Before surgery, the mean corneal astigmatism was 0.62 ± 0.39 D in the T-group and 0.54 ± 0.33 D in the S-group (p = 0.4). In the S-group, PRA was 0.73 ± 0.37 D, higher than the corresponding preoperative corneal astigmatism (p = 0.040). In the T-group, PRA was 0.58 ± 0.31 D; the variation was not statistically significant. Uncorrected VA was significantly better in the T-group vs the S-group (p = 0.007), and the best-corrected VA was comparable in the two groups.

Conclusion

The present study indicated that in eyes with very low preoperative astigmatism, 1.0 D toric IOLs were able to limit the increase of the PRA instead of those observed with the spherical IOLs. This could support the better uncorrected VA recorded in the T-group.

Comparing Visual Acuity, Low Contrast Acuity and Refractive Error After Implantation of a Low Cylinder Power Toric Intraocular Lens or a Non-Toric Intraocular Lens

Purpose

To compare uncorrected and best-corrected visual acuity, low contrast acuity, residual refraction and ocular biometry after low cylinder power toric intraocular lens (IOL) or non-toric IOL implantation.

Patients and Methods

This was a non-interventional comparative study of visual outcomes after uncomplicated cataract or refractive lens exchange surgery with either a low cylinder (Low_Cyl) or non-toric (Non_Toric) IOL of similar design implanted (AcrySof^® T2 IQ Toric IOL and AcrySof^® IQ IOL). Subjects in both groups had to have been eligible for the low cylinder IOL based on biometry. They had to have uncorrected distance visual acuity (UDVA) of 20/32 (0.2 logMAR) or better at the time of their single diagnostic study visit. Clinical evaluation included the manifest refraction, visual acuity (VA), low contrast VA and ocular biometry.

Results

A total of 94 eyes were enrolled, 51 Low_Cyl and 43 Non_Toric. The mean manifest refractive cylinder was statistically significantly lower (~0.25 D) in the Low_Toric group (p < 0.01) and significantly more eyes had 0.25 D or less of refractive cylinder in that group (p = 0.03). The orientation of the preoperative anterior corneal astigmatism was a significant cofactor, with the difference between groups more evident when astigmatism was against the rule. Uncorrected high contrast visual acuity was statistically significantly better in the Low_Toric group (p = 0.02) as was the percentage of eyes with 20/20 visual acuity (p = 0.05). Uncorrected low contrast visual acuity was not statistically significantly different in mesopic or photopic conditions.

Conclusion

The low cylinder power toric IOL provided better uncorrected visual acuity and lower residual refractive cylinder than a similar non-toric IOL after cataract surgery.

[Correction of corneal astigmatism in femtosecond laser-assisted cataract extraction surgery]

PURPOSE

To perform a comparative analysis of clinical and functional results and efficiency of corneal astigmatism correction after femtosecond laser-assisted cataract surgery (FLACS) with implantation of toric intraocular lens (TIOL) and in combination with arcuate keratotomy (FL-AC).

MATERIAL AND METHODS

The examination included 60 patients (60 eyes). The first group consisted of 30 patients (30 eyes) who underwent FLACS with implantation of TIOL (Acrysof IQ Toric, Alcon, U.S.A.); the second group consisted of 30 patients (30 eyes) who underwent FLACS in combination with FL-AC. The examination was carried out before the operation, on the 3^rd day and 3 months after surgery. Corneal astigmatism correction efficiency was analyzed using the Alpins method and graphical vector analysis.

RESULTS

Uncorrected visual acuity (UCVA) indices increased to 0.70±0.24 and 0.66±0.31 in the FLACS with TIOL and FLACS with FL-AC groups, respectively, without statistically significant differences between the groups (p=0.03). The value of the residual cylinder was significantly lower in the FLACS with TIOL group (-0.77±0.58 and -0.80±0.39) compared with FLACS with FL-AC (-1.08±0.81 and -1.18±0.63) both on day 3 (p=0.02), and 3 months after surgery (p=0.02). In the FLACS with TIOL group, a higher correction index (0.99±0.18) and a smaller difference vector (0.77±0.64) were achieved compared to the FLACS with FL-AC group (0.78±0.35 and 1.05±0.76, respectively). Corneal higher-order aberrations (HOA) significantly differed on the 3^rd day after surgery in the 3.0 mm (p=0.04) and 5.0 mm (p=0.04) zones between the groups. Endothelial cells density was 2460.50±328.40 and 2526.125±196.74 cl/mm² after 3 months of observation in the FLACS with TIOL and FLACS with FL-AC groups, respectively (p=0.61).

CONCLUSION

Both methods had comparable visual acuity results (p=0.03). FLACS with TIOL provided more effective correction of the cylindrical component of refraction to 3.0 D.

Comparison of the clinical efficacy of AcrySof® IQ and TECNIS® toric intraocular lenses: A real-world study

Corneal astigmatism significantly compromises uncorrected visual acuity (UCVA) after phacoemulsification with implantation of traditional spherical or non-spherical monofocal intraocular lens (IOL). Toric IOL provides an effective way to gain favorable postoperative UCVA for the patients with cataracts with corneal astigmatism. There are numerous types of toric IOLs; however AcrySof^® IQ toric IOL (Alcon Laboratories, Inc.) and TECNIS^® toric IOL (Johnson & Johnson Vision; Johnson & Johnson) are most frequently used in our clinical practice. The purpose of the current study was to compare the clinical efficacy of AcrySof IQ with TECNIS toric IOL implantation, and to provide a clinical basis on selecting an appropriate toric IOL before cataract surgery for patients with corneal astigmatism. A total of 30 patients with cataract (44 eyes) with corneal astigmatism [0.82-7.27 diopters (D)], who have undergone phacoemulsification with toric IOL implantation between October 2012 and December 2017, were included in the current retrospective cohort study. Patients were divided into two groups: One group (26 eyes) received the AcrySof IQ toric IOL (AcrySof group) and the other group (18 eyes) received the TECNIS toric IOL (Tecnis group). The indexes of curative effect, such as uncorrected and corrected distance visual acuity (UDVA and CDVA, respectively), refractive outcomes, contrast sensitivity (CS), IOL rotation, and satisfaction, were evaluated. Both toric IOLs significantly improved UDVA and CDVA. Postoperative mean residual astigmatism was similar in the AcrySof group and in the Tecnis group (0.75±0.50 and 0.78±0.90 D; P=0.896). There was no statistically significant between postoperative CS in the AcrySof and Tecnis groups. Rotations of >10˚ were considered to be significant and were identified in three eyes. The mean IOL rotation showed no statistically significant difference (AcrySof group, 0.24±5.54˚; Tecnis group, -0.19±6.28˚; P=0.416). The mean patient satisfaction score was 8.46±1.21 in the AcrySof group and 8.78±1.44 in the Tecnis group (P=0.260). The results of the current study indicated that patients with cataracts with corneal astigmatism undergoing phacoemulsification with AcrySof IQ and TECNIS toric IOL implantation achieved similar clinical efficacy in term of visual outcomes, refraction correction, CS, rotational stability and satisfaction.

MicroRNAs: new players in cataract

Cataract is the most common cause of blindness worldwide. Multiple factors such as aging, eye injury, diabetes mellitus, ultraviolet exposure, drug use and other ocular diseases are etiologically linked to cataractogenesis. Due to a rapid increase in aging population, age-related cataract has become the leading cause of blindness. Therefore, it is urgent to understand the molecular mechanism underlying cataractogenesis. MicroRNAs (miRNAs) are a group of endogenous, small noncoding RNAs that regulate gene expression at the post-translational level through binding with the 3'-untranslated regions of target mRNAs. Studies have shown that miRNAs play important roles in multiple cellular functions, including apoptosis, cell proliferation, senescence and stress response. Deregulated expression of miRNAs is also linked to the pathogenesis of many diseases, including ocular diseases. In our review, we focus on miRNAs that are involved in cataract development and discuss their potential applications as novel diagnostic markers and therapeutic targets.