Comparison of clinical outcomes of toric intraocular lens, Precizon vs Tecnis: a single center randomized controlled trial

Spherical aberrations and their role in modern ophthalmology

Spherical aberration is an imperfection of the optical system of the human eye. The role of spherical aberration of the human eye in the quality of vision and pseudoaccommodation is reviewed. Spherical aberration is an imperfection of the optical system of the human eye. In most cases, due to well-developed neuroadaptation, it is insignificant for the perception of the image. Nevertheless, its role in modern ophthalmology is far from straightforward. On the one hand, there are clinical scenarios in which an excess of spherical aberration degrades the retinal image and leads to a high dissatisfaction rate among patients.©Recently, there is a growing interest in the modulation of spherical aberration in the clinical setting. Modern intraocular lenses as well as laser refractive procedures are aimed at interfering with spherical aberrations of the optical system in order to increase range of pseudoaccommodation. Here, we review the role of spherical aberration of the human eye in the quality of vision and pseudoaccommodation.

Spherical Aberration of Astigmatic Corneas in a Cataract Population

PURPOSE

To study the distribution of spherical aberration (SA) in astigmatic corneas in a cataract population and the relationship between magnitude of corneal astigmatism and fourth-order corneal SA.

METHODS

Data routinely collected using a Scheimpflug camera (Pentacam; Oculus Optikgeräte GmbH) were retrospectively analyzed. Patients with a minimum age of 60 years were included. Total corneal SA (from anterior and posterior corneal surface) was obtained for a 6-mm cor-neal area aligned with the pupil center. Exclusion criteria were insufficient measurement quality, total deviation index (Belin/Ambrósio Deviation) greater than 1.60, and corneal thickness at the thinnest point of less than 490 μm. One eye per patient was chosen randomly. Eyes were divided into low (≤ 1.00 diopters [D]), moderate (> 1.00 to ≤ 2.00 D), and high (> 2.00 D) astigmatism groups according to the Scheimpflug measurements.

RESULTS

A total of 528 eyes were included in this analysis. Low astigmatism was found in 129 patients, moderate astigmatism in 265 patients, and high astigmatism in 134 patients. Mean astigmatism was 0.68 ± 0.24, 1.45 ± 0.28, and 2.91 ± 0.95 D in the low, moderate, and high astigmatism groups, respectively. Mean corneal SA in patients with moderate and high astigmatism was higher than in the low astigmatism group. The difference reached the significance level for the comparison of low and high astigmatism groups (P = .023). The fourth-order SA increased gradually with the magnitude of astigmatism with a slope of 0.015.

CONCLUSIONS

SA was significantly larger in the cataract population with high corneal astigmatism. The increase of positive sign SA with the magnitude of astigmatism suggests that patients with moderate to high astigmatism may benefit more from intraocular lenses with negative sign SA correction. [J Refract Surg. 2023;39(8):532-538.].

Comparison of clinical outcomes of Eyecryl toric and Alcon toric intra-ocular lenses - A real world study

Purpose

To compare the visual outcomes and residual astigmatism following implantation of Eyecryl toric versus Alcon AcrySof IQ toric intra-ocular lenses (IOLs).

Methods

This retrospective, observational study included 143 eyes of 141 patients who underwent phaco-emulsification, followed by implantation of Eyecryl toric IOL (n = 83 eyes) or Alcon toric IOL (n = 60 eyes) in an eye hospital in South India from 2018 to 2021. At 1 month post-op, the uncorrected distance visual acuity (UCVA), best corrected distance visual acuity (BCVA), and residual astigmatism of the toric IOL were compared and analyzed.

Results

The mean pre-op corneal astigmatism was 2.02 ± 0.81 D and 1.70 ± 0.68 D in the Alcon and Eyecryl groups, respectively (P = 0.005). The mean post-op corneal astigmatism at 1 month was 0.50 ± 0.51 D and 0.36 ± 0.42 D in the Alcon and Eyecryl groups, respectively, with no statistically significant difference between them (P = 0.87). The mean post-op UCVA in logarithm of minimum angle of resolution (logMAR) at 1 month was similar between the groups at 0.17 ± 0.18 and 0.17 ± 0.16 in the Alcon and Eyecryl groups, respectively (P = 0.98). The mean post-op BCVA in logMAR at 1 month was 0.06 ± 0.09 and 0.03 ± 0.10 in the Alcon and Eyecryl groups, respectively (P = 0.02).

Conclusion

Both Eyecryl toric and Alcon AcrySof IQ toric IOLs showed comparable post-operative outcomes in terms of UCVA and residual astigmatism. The post-op BCVA was clinically similar between groups but statistically better in the Eyecryl toric group.

One-year long-term clinical outcomes following diffractive trifocal toric intraocular lens implantation: retrospective observational case series study

BACKGROUND

Trifocal intraocular lens (IOL) provides three foci for the external light to the eye. The reduction of corneal astigmatism makes three foci to clearly focus on the fovea. This study aimed to evaluate one-year clinical outcomes for near, intermediate, and far distance visual acuity and satisfaction in patients implanted with diffractive trifocal toric IOLs.

METHODS

This retrospective observational case series study was based on the medical records of patients who undergone uncomplicated cataract surgery with implantation of a trifocal toric IOL (POD AY 26P F-T FineVision Toric; PhysIOL SA, Liège, Belgium). Eyes with corneal astigmatism greater than 1.00 diopters were included. Postoperative evaluations included uncorrected near, intermediate, and distance and corrected distance visual acuity; defocus curves; and contrast sensitivity measured at both three months and one-year postoperatively. Subjective satisfaction was evaluated based on three kinds of questionnaires for spectacle dependence, quality of vision, and overall satisfaction.

RESULTS

Postoperative uncorrected distance visual acuity and that at 33, 43, 50, 60, and 80 cm at one-year were 0.07±0.08, 0.22±0.11, 0.17±0.11, 0.14±0.10, 0.14±0.10, and 0.15±0.10 logarithm of the minimal angle of resolution (logMAR), respectively. A smooth range of good visual acuity was found on defocus curve. Subjective scores for spectacle dependence, quality of vision, and subjective satisfaction showed no significant differences between three months and one-year postoperatively. The mean amount of IOL axis rotation was 2.14±1.72° (range: 0.2-5.1°) at one-year postoperatively.

CONCLUSIONS

Implantation of a diffractive trifocal toric IOL for cataract, presbyopia, and astigmatism correction provided good refractive and visual outcomes, relatively smooth range of intermediate vision, and high levels of visual quality and patient satisfaction until one-year after surgery.

Effects of Modified Haptics on Surgical Outcomes and Rotational Stability of Toric Intraocular Lens Implantation

PURPOSE

To assess the rotational stability of a new toric intraocular lens (IOL), TECNIS toric II (toric II), which is a modified version of the TECNIS toric IOL (toric I) with frosted haptics (Johnson & Johnson).

METHODS

A total of 101 eyes of 101 patients who had been treated with phacoemulsification and toric IOL implantation were included. Before and 1 day, 1 week, and 1 month after surgery, uncorrected (UDVA) and corrected (CDVA) distance visual acuity were measured. Preoperative corneal astigmatism and postoperative manifest refractive astigmatism at 1 day and 1 month were analyzed. At 1 day and 1 month postoperatively, the amount of IOL axis misalignment from the intended orientation, tilt, and decentration were measured using anterior segment optical coherence tomography.

RESULTS

Fifty-one eyes received the toric I IOL and 50 eyes received the toric II IOL. Toric I IOLs showed a significantly larger amount of axis misalignment than toric II IOLs at both 1 day (9.6 ± 7.6° vs 5.4 ± 4.8°, P = .003) and 1 month (9.1 ± 7.8° vs. 4.7 ± 4.2°, P = .003) postoperatively.The proportion of eyes with misalignment greater than 10° was significantly larger with toric I than toric II IOLs (P < .001). There were no significant differences between IOLs in the amount of residual astigmatism, UDVA, CDVA, and amount of tilt and decentration at 1 day and 1 month postoperatively.

CONCLUSIONS

The TECNIS toric II IOL with frosted haptics has significantly improved rotational stability compared to its previous model. [J Refract Surg. 2022;38(10):648-653.].

Toric intraocular lenses: Expanding indications and preoperative and surgical considerations to improve outcomes

Since the introduction of the first toric intraocular lens (IOLs) in the early 1990s, these lenses have become the preferred choice for surgeons across the globe to correct corneal astigmatism during cataract surgery. These lenses allow patients to enjoy distortion-free distance vision with excellent outcomes. They also have their own set of challenges. Inappropriate keratometry measurement, underestimating the posterior corneal astigmatism, intraoperative IOL misalignment, postoperative rotation of these lenses, and IOL decentration after YAG-laser capsulotomy may result in residual cylindrical errors and poor uncorrected visual acuity resulting in patient dissatisfaction. This review provides a broad overview of a few important considerations, which include appropriate patient selection, precise biometry, understanding the design and science behind these lenses, knowledge of intraoperative surgical technique with emphasis on how to achieve proper alignment manually and with image-recognition devices, and successful management of postoperative complications.

Transitional conic toric intraocular lens evaluation after femtosecond laser-assisted cataract surgery using intraoperative aberrometry

PURPOSE

To assess refractive and visual outcomes following phacoemulsification with femtosecond laser-assisted cataract surgery (FLACS) using intraoperative aberrometry and implantation of a toric intraocular lens (IOL) in eyes with different degrees of astigmatism.

METHODS

One hundred two eyes of 70 patients who underwent implantation of the transitional toric 565 Precizon IOL (Ophtec BV) were enrolled. FLACS, capsular tension ring insertion, and intraoperative aberrometry were performed. Main outcome measures were refractive error, uncorrected- and corrected distance snellen decimal visual acuity values (UDVA and CDVA, respectively), and IOL rotation. Specifically, a vector analysis was carried out with J0 and J45 evaluation. Eyes were evaluated 1-year after surgery.

RESULTS

Overall, 94.12% (96 eyes) and 100% (102 eyes) of the eyes showed a spherical equivalent (SE) within ± 0.50D and ± 1.00D, respectively. The mean SE and refractive cylinder were - 0.06 ± 0.29D and - 0.23 ± 0.37D, respectively. Vector analysis revealed that 100% of the eyes were within ± 0.50D for the J0 and J45 cylindrical components. The mean toric axis rotation was 1.10 ± 1.71° (from 0° to 5°), 77% (79 eyes), and 100% (102 eyes) of the eyes showed UDVA and CDVA of 20/25, respectively. The postoperative mean values of monocular UDVA and CDVA were 0.88 ± 0.17 and 0.96 ± 0.07 (about 20/20), respectively. No patient required IOL realignment during the postoperative follow-up.

CONCLUSIONS

The present study suggests that the use of the Precizon IOL after FLACS, using intraoperative aberrometry in patients with different amounts of astigmatism, provides good visual acuity, accurate refractive outcomes, and excellent rotational stability.

Influence of frosted haptics on rotational stability of toric intraocular lenses

We investigated the unfolding property and rotational stability of a new toric intraocular lens (IOL); TECNIS toric II (toric-II, ZCW, Johnson & Johnson) that is an improved version of TECNIS toric IOL (toric-I, ZCV). Both IOLs are based on an identical platform, except for the frosted haptics with toric-II IOL. The study consisted of two parts; experimental study and clinical, retrospective, case series. Experimental study indicated that the overall time from IOL ejection to unfolding to 11 mm was significantly shorter with toricII than toric-I IOLs (p = 0.032), due to the earlier separation of the haptics from the optic with toric-II IOL. Clinical study included 131 eyes of 99 patients who had undergone phacoemulsification and toric IOL implantation. At 3 months postoperatively, toric-II IOL showed significantly better rotational stability than toric-I IOL, including smaller residual manifest astigmatism (p = 0.018), less amount of axis misalignment from the intended axis (p = 0.04), lower incidence of misalignment > 10º (p = 0.0044), and less degree of prediction errors (p = 0.043). Postoperative uncorrected distance visual acuity tended to be better in the toric-II than in the toric-I groups, with marginal statistical difference (p = 0.057). TECNIS toric II IOL with the frosted haptics showed significantly better rotational stability than its predecessor, probably due to quicker unfolding and greater friction with the capsular bag.

Comparison of penetrating femtosecond laser-assisted astigmatic keratotomy and toric intraocular lens implantation for correction of astigmatism in cataract surgery

This study tried to compare the clinical outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for astigmatism correction and identify factors affecting the efficacy of FSAK and toric IOL implantation in astigmatism correction. This retrospective case series comprised patients with corneal astigmatism ranging between 0.5 D and 4.5 D. Patients underwent FSAK or toric IOL implantation for cataract treatment and correction of astigmatism at the Samsung Medical Center, a tertiary surgical center, between April 2016 and December 2018. All patients underwent examination before and at three months after the surgery for comparative evaluation of refractive astigmatism, corneal high order aberrations and irregularity index. The astigmatism correction was analyzed by the Alpins method. Subgroup analysis of preoperative factors was based on the extent of target-induced astigmatism (TIA), the degree of astigmatism, and astigmatism classification based on topography. Thirty-one eyes underwent toric IOL implantation and 35 eyes underwent FSAK. The refractive astigmatism was significantly decreased in both toric IOL (P = 0.000) and FSAK group (P = 0.003). The correction index (CI) of refractive astigmatism was 0.84 ± 0.39 in the toric IOL and 0.71 ± 0.60 in the FSAK group. There was no difference between the two groups (P = 0.337). The CI of the FSAK group was significantly lower than in the toric IOL group when TIA was more than 1.5 D (P = 0.006), when correcting against-the-rule (P = 0.017), and limbus-to-limbus astigmatism (P = 0.008). In conclusion, toric IOL implantation is an effective and safe procedure for correcting preoperative astigmatism in cataract surgery in the short-term observation.

Evaluation of Astigmatism-Correcting Efficiency and Rotational Stability after Cataract Surgery with a Double-Loop Haptic Toric Intraocular Lens: A 1-Year Follow-Up

OBJECTIVES

The aim of this study was to assess the clinical outcomes, predictability of results, efficiency of astigmatism correction, and rotational stability of the Bi-Flex 677TAY (Medicontur Medical Engineering Ltd., Zsámbék, Hungary) monofocal toric intraocular lens (IOL) designed for cataract patients with astigmatism.

METHODS

The IOLs were implanted either mono- or binocularly, following routine cataract surgery. Visual and refractive outcomes, as well as off-axis rotation were assessed throughout a 1-year follow-up period. All clinical data for this work were collected retrospectively. Vector analysis based on the Alpins method was performed to assess the efficiency of astigmatism correction.

RESULTS

No complications or adverse events occurred during surgery or the follow-up period. IOL implantation brought 88% of eyes into the ±0.50 D, and 100% into the ± 1.00 D range compared to the target spherical equivalent refraction, emmetropia. Astigmatism correction brought similar results: 94% of eyes had a residual cylindrical error of not higher than ±0.50 D, and 97% were within ±1.00 D. Vector analysis resulted in a correction index of 0.96 and a difference vector of 0.17. Both refractive and visual outcomes showed long-term stability. During the 12-month follow-up period, no eyes had a rotation of >5°. Absolute rotation after 1 year was 1.42 ± 1.89° (median = 0°), while signed rotation was 1.06 ± 2.12° (median = 0°).

CONCLUSION

The Bi-Flex 677TAY monofocal toric IOL, designed by Medicontur Medical Engineering Ltd., represents an efficient and safe solution for cataract patients with astigmatism. Clinical and refractive outcomes are predictable, and rotational stability ensures long-term visual comfort.

Evaluating Rotational Stability of an Extended Depth of Focus Toric Intraocular Lens Using a Slit Lamp and Image-Based Analysis

Purpose

To evaluate the rotational stability of a toric extended depth of focus (EDOF) intraocular lens (IOL), using either slit lamp evaluation or image-processing software.

Setting

Three clinical practices in the USA.

Design

Prospective unmasked randomized clinical trial.

Methods

Subjects presenting for routine cataract surgery that were interested in improved near vision received toric EDOF lenses (TECNIS Symfony^® Toric) in both eyes. The measures of interest in the current analysis were the change in orientation of the IOL between 1 day, 1 month and 3 months postoperative. Orientation was measured at the microscope on the day of surgery, and with the slit lamp at all other visits. Day 1, 1-month and 3-month images of the lens orientation were captured with a slit lamp camera. Differences in orientation were recorded and analyzed.

Results

A total of 150 eyes had IOL orientation data available. Image analysis showed mean absolute lens orientation changes from 1 day to 1 month and 3 months of less than 2 degrees. The percentage of lenses exhibiting rotation of ≤5 degrees between any measured time points was 97% or higher. Results were similar, but significantly more variable, when IOL orientation was measured at the slit lamp.

Conclusion

The toric EDOF lens evaluated here demonstrated rotational stability that exceeded the prior ANSI standard. The best method to determine IOL orientation changes was through image analysis.  

Early-stage clinical outcomes and rotational stability of TECNIS toric intraocular lens implantation in cataract cases with long axial length

Background

A major focus of toric intraocular lens (IOL) implantation is the rotational stability, especially in the patients with long axial length (AL). In this study, we aimed to evaluate the clinical outcomes after implantation of TECNIS toric IOL in eyes with long AL and identify factors influencing their early-stage stability with preoperative corneal astigmatism.

Methods

The study population consisted of 64 eyes from 52 cataract patients, and these patients had preoperative corneal astigmatism between 1.0 and 3.7 diopters (D) and underwent phacoemulsification and TECNIS toric IOL implantation. Ophthalmic biological measurements were carried out preoperatively, including AL, anterior chamber depth (ACD), lens thickness (LT), vitreous length (VL), anterior chamber volume (ACV), sulcus-to-sulcus (STS) and keratometric value (K). Clinical examinations, including visual acuity, manifest refraction, keratometry, digital anterior segment photographs with pupillary dilation, were performed at 1 and 3 months after surgery.

Results

The mean best corrected distance visual acuity (BCDVA) was improved from 0.93 ± 0.35 logarithms of the minimal angle of resolution (logMAR) preoperatively to 0.07 ± 0.10 logMAR postoperatively at 3 months after surgery. The mean residual astigmatism (RAS) was 0.91 ± 0.74D at 3 months, which was significantly decreased compared with the preoperative corneal astigmatism of 1.71 ± 0.55 D. The mean absolute rotation of TECNIS toric IOL at 1 and 3 months was 7.42 ± 11.32 degree (°) (0–79°) and 7.48 ± 11.19°(0–79°), respectively. The mean area of capsulorhexis and the overlapped area between capsulorhexis and IOL optic intraoperatively was 21.04 ± 3.30 mm² and 7.40 ± 2.87 mm².A positive correlation was found between IOL rotation and the area of capsulorhexis (p = 0.017) at 3 months after surgery. No correlation was found between IOL rotation and AL (p = 0.876), ACD (p = 0.387), LT (p = 0.523), VL (p = 0.546), ACV (p = 0.480), STS (p = 0.884), K1 (p = 0.429), K2 (p = 0.644), average of K1 and K2 (p = 0.520), intraoperative IOL axial direction (p = 0.396), preoperative corneal astigmatism (p = 0.269) or the overlapped area between capsulorhexis and IOL optic intraoperatively (p = 0.131) .

Conclusions

The large CCC was a risk factor for toric IOL rotation. An appropriately smaller sized CCC was conducive to increase the rotational stability of TECNIS toric IOL implantation in cataract cases with long AL.

Comparative effects of various types of toric intraocular lenses on astigmatism correction

BACKGROUND

Currently, various types of toric intraocular lenses (IOL) have been manufactured and can be divided into three types according to the location of correction component; front-toric IOL (correction on anterior IOL surface), back-toric IOL (correction on posterior IOL surface), and bi-toric IOL (correction on both anterior and posterior IOL surfaces). In this study, we aimed to investigate the effectiveness of reducing corneal astigmatism of either normal or post-penetrating keratoplasty (PKP) corneas according to the type of implanted toric IOLs.

METHODS

Medical records were retrospectively reviewed in 370 patients who had undergone phacoemulsification with posterior chamber toric IOL insertion (front-toric IOL, back-toric IOL or bi-toric IOL). Subjects were divided into 2 groups; subjects who had no history of corneal disease with corneal astigmatism more than 1.00 diopters (D) (G1) and subjects who received previous PKP with all corneal sutures removed and had corneal astigmatism more than 1.25 D (G2). Preoperatively intended target from SRK/T was evaluated. Refractive astigmatism and its vector analysis (J0, J45), mean numerical error (MNE) and mean absolute error (MAE) were assessed at least a month after cataract surgery.

RESULTS

Mean preoperative corneal astigmatisms were 2.2 D and 4.0 D in G1 and G2, respectively. There was significant reduction of mean postoperative refractive astigmatism to 0.89 D in G1 and to 2.33 D in G2. In G1, bi-toric IOL showed significantly more improved refractive astigmatism than back-toric IOL. In G2, no difference in refractive astigmatism according to toric IOL type was observed. While G2 showed no difference in MNE among toric IOLs, in G1, bi-toric IOL showed significant hyperopic shift compared to back-toric IOL. In both groups, there was no significant difference in MAE according to type of IOL. No postoperative complications were observed.

CONCLUSION

Our study suggests that all types of toric IOL are beneficial in correcting astigmatism of normal and post-PKP corneas. Noticeably, bi-toric IOL showed significantly better results in refractive astigmatism than back-toric IOL in normal cornea. However, bi-toric IOL showed a more hyperopic shift compared to back-toric IOL. Among post-PKP corneas, all types of toric IOL showed similar results.