Evaluation of rotation and visual outcomes after implantation of monofocal and multifocal toric intraocular lenses

Evaluating the small aperture intraocular lens: depth of focus and the role of refraction and preoperative corneal astigmatism in visual performance

PURPOSE

To evaluate depth of focus (DOF) and visual acuities (VAs) by manifest refractive spherical equivalent (MRSE) and degree of preoperative corneal astigmatism with the IC-8 small aperture intraocular lens (SA IOL) (Apthera).

SETTING

21 investigational sites in the United States.

DESIGN

Prospective, multicenter, open-label, parallel-group, nonrandomized, examiner-masked, 1-year clinical study.

METHODS

Included patients had cataract and ≤1.5 diopters (D) preoperative corneal astigmatism. Patients received either the SA IOL in 1 eye targeted to -0.75 D and a monofocal or monofocal toric IOL in the other targeted to plano (SA IOL group) or bilateral monofocal/monofocal toric IOLs targeted to plano (control group). Monocular and binocular assessments included defocus curves and uncorrected VAs (distance, intermediate, and near) by postoperative MRSE; monocular VAs were assessed by degree of preoperative corneal astigmatism.

RESULTS

The SA IOL group (n = 343) achieved 0.82 D additional binocular DOF vs the control group (n = 110), and SA IOL eyes achieved 0.91 D additional monocular DOF over fellow eyes. Across all MRSEs, the SA IOL group achieved monocular uncorrected VAs of 20/40 or better and binocular uncorrected VAs of 20/32 or better across all distances. In addition, SA IOL eyes with higher (1.0-1.5 D) vs lower (<1.0 D) preoperative corneal astigmatism achieved equivalent monocular uncorrected VAs.

CONCLUSIONS

The SA IOL provides increased DOF vs monofocal/monofocal toric IOLs and consistent monocular and binocular vision across several postoperative MRSEs and up to 1.5 D of preoperative corneal astigmatism, giving patients with cataract and mild astigmatism the potential for an extended range of vision and reliable visual outcomes.

Evaluation of Clinical Results of Implantation of Toric Intraocular Lenses Including their Rotational Stability

PURPOSE

The aim of the study was to evaluate the clinical results of the implantation of the toric intraocular lens Acrysof IQ Toric SN6AT3_8 (Alcon Laboratories, Inc., Fort Worth, TX, USA), including an evaluation of its rotational stability.

MATERIAL AND METHODS

30 eyes of 16 patients (4 males, 12 females; mean age 68 years) with regular corneal astigmatism ranging from -1.5 to -4.0 Dcyl were included in this retrospective study. All the patients underwent uncomplicated cataract surgery with the implantation of a toric intraocular lens (TIOL) at the Department of Ophthalmology of the Faculty of Medicine and Dentistry of Palacký University in Olomouc and University Hospital Olomouc during the course of 2020. Follow-up examinations were performed 3-6 months after cataract surgery. We monitored the resulting uncorrected distance visual acuity (UDVA), postoperative refraction, rotational stability of the implanted lens and subjective patient satisfaction.

RESULTS

mean preoperative corneal astigmatism was -2.41 ±0.67 Dcyl. UDVA improved from a mean value of 0.45 ±0.25 (expressed in decimal Snellen optotype values) to 0.91 ±0.16. The spherical equivalent value of 0.41 ±2.92 improved to -0.11 ±0.27 postoperatively. The mean deviation from the planned axis was 4.87 ±4.75. Subjective satisfaction was rated by patients on a scale of 1-5, with a mean score of 1.5.

CONCLUSION

TIOL implantation is a safe and effective solution for patients with corneal astigmatism and cataract. Our results demonstrate improved UDVA, rotational stability of the TIOL and subjective patient satisfaction with the outcome of the surgery.

Repositioning Rates of Toric IOLs Implanted in Cataract Surgery Patients: A Retrospective Chart Review

Purpose

To determine the incidence of postoperative repositioning of toric intraocular lenses (IOLs) due to clinically significant rotation.

Patients and Methods

This study included consecutive cataract patients with pre-existing astigmatism who had undergone cataract surgery with toric IOL implantation by a single experienced surgeon. Case records of patients who were recommended to undergo toric IOL repositioning surgery due to clinically significant postoperative IOL rotation from the implanted axis were identified. The need for a secondary intervention to manage residual astigmatism was based upon postoperative residual astigmatic error ≥0.75 D, the patient's qualitative dissatisfaction with the level of postoperative distance vision, dilated post-op examination, and confirmation of the significant potential for astigmatism reduction.

Results

Case records of 993 eyes implanted with AcrySof toric (N = 362), Tecnis Toric I (N = 53), Tecnis Toric II (N = 308), or enVista Toric IOLs (N = 270) were included. Postoperative toric IOL repositioning was recommended in 16 eyes (1.6%). The repositioning rate was highest in the eyes implanted with Tecnis Toric I (5.7%), followed by AcrySof Toric (2.2%), enVista Toric IOLs (1.1%), and Tecnis Toric II (0.6%).

Conclusion

This real-world analysis of eyes implanted with toric IOLs revealed that the rate of surgical IOL repositioning due to clinically significant IOL rotation was lower than 2% for enVista and Tecnis Toric II IOLs. When needed and with appropriate planning, toric IOL repositioning can be very successful.

Extensive misalignment of plate-haptic rotationally asymmetric multifocal toric intraocular lens

PURPOSE

Plate-haptic rotationally asymmetric multifocal toric intraocular lenses (IOL) (Lentis Comfort Toric) occasionally rotate extensively after surgery. We conducted the current study to investigate the incidence of extensive misalignment of this IOL and its association with clinical parameters.

STUDY DESIGN

Retrospective case series.

SUBJECTS AND METHODS

Data were collected from patients who had undergone phacoemulsification and implantation of a plate-haptic multifocal toric IOL.

RESULTS

Among 332 eyes, extensive misalignment of toric IOLs ≥ 45º occurred in 3.3% (11 eyes). The amount of misalignment in eyes with extensive misalignment was 81.6 ± 22.9º, while in those without extensive misalignment, it was 3.0 ± 2.7º. The eyes with extensive misalignment showed significantly greater axial length (p < 0.001), larger corneal diameter (p = 0.034), and flatter corneas (p = 0.044) than those without extensive misalignment. Repositioning surgery to correct toric IOL misorientation was conducted in 9 eyes between 7 and 28 days after cataract surgery. In 2 eyes, repositioning surgery was carried out twice.

CONCLUSIONS

In majority of cases plate-haptic multifocal toric IOLs showed satisfactory rotational stability, but extensive misalignment ≥ 45º occurred in 3.3% of cases.

Vision and patient-reported outcomes with nondiffractive EDOF or neutral aspheric monofocal intraocular lenses

PURPOSE

To compare outcomes in patients who underwent cataract extraction with implantation of nondiffractive extended depth-of-focus (ND-EDOF; Alcon AcrySof Vivity) or neutral aspheric monofocal (Bausch & Lomb enVista) intraocular lenses (IOLs).

SETTING

Academic medical center.

DESIGN

Prospective single-center double-arm patient- and assessor-masked randomized controlled trial.

METHODS

Patients were randomized to receive either a ND-EDOF or monofocal IOL in both eyes, targeted for emmetropia. Uncorrected and corrected (CDVA) distance visual acuities, distance-corrected intermediate visual acuity (DCIVA), distance-corrected near visual acuity (DCNVA), level of spectacle independence, and severity of photic phenomena were assessed at 3 months postoperatively.

RESULTS

56 patients were enrolled, of which 24 in the ND-EDOF group and 27 in the monofocal group completed follow-up. The binocular mean CDVA, DCIVA, and DCNVA were 20/20, 20/19, and 20/21 for the ND-EDOF IOL and 20/18 ( P = .188), 20/31 ( P < .001), and 20/30 ( P = .004) for the monofocal IOL, respectively. At intermediate, 88% of the ND-EDOF vs 30% of the monofocal patients had a binocular DCIVA of 20/25 or better ( P < .001). Moderate or severe glare occurred in 20.8% of ND-EDOF vs 7.4% of monofocal patients ( P = .228), whereas moderate or severe halos occurred in 16.7% of ND-EDOF vs 11.1% of monofocal patients ( P = .697).

CONCLUSIONS

The ND-EDOF and monofocal IOLs provided similarly excellent distance vision. Patients implanted with the ND-EDOF IOL had 2 more lines of vision at both intermediate and near, and a greater proportion reported spectacle independence. Most patients in both groups reported low severity of photic phenomena.

Optical Quality Variation of Different Intraocular Lens Designs in a Model Eye: Lens Placed Correctly and in an Upside-Down Position

INTRODUCTION

Intraocular lenses (IOLs) may lose their optical quality if they are not correctly placed inside the capsular bag once implanted. One possible malpositioning of the IOL could be the implantation in an upside-down position. In this work, three aspheric IOLs with different spherical aberration (SA) have been designed and numerically tested to analyse the optical quality variation with the IOL flip, and misalignments, using a theoretical model eye.

METHODS

Using the commercial optical design software OSLO, the effect of decentration and tilt was evaluated by numerical ray tracing in two conditions: in their designed position and flipped with respect to the planned position (IOL is implanted upside down). The theoretical model eye used was the Atchison model eye. Seven IOL designs of +27.00 diopters were used: a lens with negative SA to correct the corneal SA, a lens to partially correct the corneal SA, and a lens to not add any SA to the cornea (aberration-free IOL). These lenses were designed with the aspherical surface located on the anterior and posterior IOL surface. A lens with no aspherical surfaces was also included. For the optical quality analysis, the modulation transfer function (MTF) was used, together with the Zernike wavefront aberration coefficients of defocus, astigmatism, and primary coma.

RESULTS

Off-centring and tilting the IOL reduced overall MTF values and increased wavefront aberration errors. With the IOL correctly positioned within the capsular bag, an aberration-free IOL is the best choice for maintaining optical quality. When the IOL is flipped inside the capsular bag, the optical quality changes, with the aberration-free IOL and the IOL without aspheric surfaces providing the worst results. With the lens in an upside-down position, an IOL design to partially correct corneal SA shows the best optical quality results in decentration and tilt, in terms of MTF and wavefront aberrations.

CONCLUSION

The aberration-free IOL is the best choice when minimal postoperative errors of decentration or tilt are predicted. With IOL flip, the negative SA lens design is the best choice, regarding the root mean square wavefront aberrations. However, in a proper IOL implantation, the IOL designed to partially compensate the corneal SA including asphericity on its posterior surface is the better possible option, even in the presence of decentration or tilt.

Incidence and Risk Factors of Repositioning Surgery to Correct Misalignment of Toric Intraocular Lenses after Cataract Surgery: A Single-Center Retrospective Observational Study

PURPOSE

The aim of this study was to analyze the incidence and outcomes of repositioning surgery to correct misalignment of several toric intraocular lenses (IOLs) after cataract surgery.

METHODS

In this retrospective study, patients who underwent repositioning surgery to correct misalignment of toric IOLs following cataract surgery between January 2019 and December 2021 were enrolled. The medical data on patients' age, gender, preoperative axial length, corneal astigmatism, the axis of astigmatism, IOL models, IOL axis, uncorrected distance visual acuity, residual refraction, and postoperative outcomes were analyzed.

RESULTS

Among the 1,135 eyes implanted with toric IOLs at Qingdao Eye Hospital, 23 (2.026%, 23/1,135) underwent repositioning surgery. Univariate analysis revealed that the incidence of repositioning surgery was significantly lower with AcrySof (0.636%, 5/786) than with ZEISS (2.959%, 5/169) and TECNIS (7.222%, 13/180) IOL platforms; the incidence of repositioning surgery with monofocal toric IOLs (1.169%, 11/941) was significantly lower than multifocal toric IOLs (6.186%, 12/194) (p < 0.001); additionally, a significant difference in age was also observed (p = 0.002). Multivariate logistic regression analysis showed that the IOL platform (p = 0.004) and younger age (p = 0.006) were independent risk factors for repositioning surgery.

CONCLUSION

The incidence of repositioning surgery of toric IOLs after cataract surgery was 2.026%. It was linked to the IOL platform, multifocal toric IOLs, and younger age.

Effect of decentration, tilt and rotation on the optical quality of various toric intraocular lens designs: a numerical and experimental study

Toric intraocular lenses (T-IOLs) may lose their optical quality if they are not correctly positioned inside the capsular bag once implanted. In this work, T-IOLs with cylinder powers of +1.50, +4.50 and +7.50 D and differing degrees of spherical aberration have been designed, manufactured and tested in vitro using a commercial optical bench that complies with the requirements of standard ISO 11979-2. Moreover, the effect of tilt and rotation on optical quality was assessed by means of numerical ray tracing on an astigmatic eye model, while the effect of decentration was evaluated numerically and experimentally.

Outcomes of a Toric Monofocal Piggyback Intraocular Lens for Residual Astigmatic Refractive Error in Pseudophakic Eyes

PURPOSE/AIM

To evaluate the visual outcomes, refractive outcomes and rotational stability of a toric piggyback intraocular lens (1stQ AddOn, GmbH, Mannheim, Germany) for astigmatic refractive error in pseudophakic eyes.

MATERIALS AND METHODS

Visual and refractive outcomes were assessed based on the standard graphs for reporting refractive surgery outcomes. Rotational stability was assessed according to the Intraocular Lens (IOL) standards of the International Organisation for Standards.

RESULTS

Twenty-two eyes of 17 patients (age: 65.1 ± 9.3 years) underwent toric piggyback IOL insertion. After a minimum follow-up of 3 months, 18 eyes (82%) achieved an uncorrected distance visual acuity (UDVA) of 0.00 logMAR (20/20) or better and all eyes achieved 0.1 logMAR (20/25). Mean UDVA improved from 0.27 ± 0.03 to 0.12 ± 0.03 and 0.04 ± 0.04 at one and 3 months (all p < .05). Nineteen eyes (86%) achieved an UDVA at least equal to the pre-operative corrected distance visual acuity (CDVA). No eyes lost more than one line of CDVA. All eyes achieved within 0.5D of target spherical equivalent (SE). In 18 eyes (82%), the residual astigmatism magnitude was 0.5D or less. The mean absolute difference between the target axis and the achieved axis 1 and 3 months postoperatively was 2.5° ± 2.7° and 3.2° ± 3.3°, respectively. The final IOL orientation was within 10 degrees of target axis in 19 of 22 (86.4%) eyes, within 20 degrees in 21 of 22 (95.2%) eyes and within 30 degrees in 22 of 22 (100%) eyes. IOL rotational repositioning was required in two eyes (9.1%).

CONCLUSIONS

In this cohort of patients, the 1stQ AddOn toric monofocal piggyback IOL resulted in very good visual and refractive outcomes and showed reasonable rotational stability. This IOL appears to be an effective treatment option for residual astigmatic refractive error in pseudophakic eyes.

Patient Expectation, Satisfaction and Clinical Outcomes with a New Multifocal Intraocular Lens

Purpose

To report patient expectations, visual performance and satisfaction with AcrySof IQ PanOptix multifocal intraocular lens in a heterogeneous patient group. Additionally, determine if identifiable pre-operative characteristics can predict post-operative satisfaction.

Methods

Data were prospectively collected for 67 consecutive patients (134 eyes) who underwent bilateral Panoptix implantation in a private ophthalmology clinic. A pre-operative questionnaire was completed regarding vision satisfaction, visual phenomena and expectations. Routine clinical parameters were collected 1 month and follow-up questionnaire administered 3 months post-operatively.

Results

Post-operative unaided distance vision was 20/20 (0.01 ± 0.10) and binocular near vision 20/25^-2 (N5; 0.14 ± 0.06). Patients satisfied with vision increased from 6% (n=4) unaided and 48% (n=32) aided pre-operatively to 94% (n=63) unaided post-operatively (p<0.001). There was marked increase in frequency of halo from 14% (n=9) to 69% (n=46; p<0.001) but no corresponding increase in how bothersome this symptom was (p=0.193) nor the frequency of other visual phenomena. Worse post-operative vision and fluctuating vision were associated with lower post-operative satisfaction. There was no difference in satisfaction or residual astigmatism in those implanted with toric lenses. A total of 96% (n=64) of patients were spectacle-free at 3-months and would recommend this procedure to others.

Conclusion

This study supports the trend towards increased patient expectations of multifocal intraocular lenses, matched by excellent visual outcomes and satisfaction. Visual phenomena may be less troubling with new multifocal lenses than previously reported. A pre-operative questionnaire may be a useful education tool but could not isolate pre-operative characteristics that predict post-operative satisfaction.

[Performance of a new 7 mm intraocular lens with follow-up over 1.5 years]

BACKGROUND

Good visibility over the entire fundus is mandatory for optimal diagnostics and treatment of retinal pathologies. If an IOL implantation is planned in the context of retinal pathologies, a model with an enlarged optic diameter offers various advantages. The two most important benefits are an enhanced view at the fundus periphery and an improvement of the IOL positional stability especially with combined vitrectomy and the use of gas or silicone oil tamponades. The purpose of this study was to evaluate the performance and positional stability of a new 7 mm IOL.

MATERIAL AND METHODS

This prospective study included 55 eyes of 39 patients who were scheduled for standardized cataract surgery and received a monofocal 7.0 mm optic IOL (Aspira-aXA, HumanOptics). An incision size of 2.0 mm was chosen. Follow-up visits were performed 1 week (1W), 1 month (1M), 4 months (4M) and 1.5 years (1.5J) postoperatively. Measurements included subjective refraction, uncorrected and corrected distance visual acuity (UDVA and CDVA) as well as IOL stability regarding decentration, tilt and rotation (IOLs had a pseudomarking on the periphery of the optics).

RESULTS

Except for the postoperative occurrence of an Irvine-Gass syndrome in one eye, no intraoperative or postoperative complications were reported. The CDVA did not change significantly (p = 0.40) within the postoperative course from 1 month (median 0.00 logMAR; -0.10 to 0.22 logMAR) to 1.5 years (median 0.00 logMAR; -0.10 to 0.10 logMAR). The IOL was found to be stable over the postoperative course as decentration was < 0.02 mm and tilt < 5.5°. There was a median rotation of 1.8° (0.0-13.4°) within the first postoperative week, which was not significantly different from the rotation between surgery and 1.5 years (median 1.4°; 0.0-10.9°).

CONCLUSION

With comparable functional performance and the same small incision size as with usual 6.0 mm IOLs, the Aspira-aXA offers the advantages of a 7.0 mm optic in the diagnostics and treatment of peripheral retinal pathologies. In addition, the lens shows good position stability in the capsular bag.

Subjective and objective clinical outcomes of a new trifocal toric intraocular lens and effect of femtosecond laser cataract surgery

PURPOSE

To evaluate the clinical outcomes and quality of life following implantation of PanOptix toric intraocular lens (IOL) and to compare the outcomes following femtosecond laser assisted cataract surgery (FLACS) and standard cataract surgery (SCS).

METHODS

This comparative retrospective study included 79 eyes of 55 patients underwent cataract or refractive lens exchange surgery between April 2017 and January 2020 in Bayindir Hospital and Kaskaloglu Eye Hospital. Corneal (CA) and refractive astigmatism (RA), uncorrected visual acuities for distant, intermediate, and near (UDVA, UIVA, and UNVA), low contrast distance visual acuity, rotational stability, defocus curves, photopic and mesopic contrast sensitivity (CS), visual function-14 (VF-14) test, presence of dysphotopsia, and need for spectacles were evaluated at postoperative third month. Outcomes were compared between FLACS and SCS group.

RESULTS

The mean UDVA, UIVA, and UNVA were 0.05 ± 0.07, 0.08 ± 0.08, and 0.06 ± 0.07 logMAR, respectively. All patients achieved ⩾0.3 logMAR uncorrected visual acuity for all distances. UDVA was found significantly better in FLACS group (p = 0.03). All eyes had ⩽1 D of subjective postoperative RA. Defocus curve had two peaks at 0 and -1.50 D. Spectacle independence was achieved in 88.7% of patients. Photopic and mesopic CS was within normal range in all patients. The mean VF-14 score was 98 ± 2. The mean IOL axis rotation was 2.1° ± 2.3°. Only one patient reported seeing disturbing halos.

CONCLUSIONS

This trifocal toric IOL effectively reduced refractive astigmatism and provided excellent visual outcomes with high spectacle independence, patients' satisfaction, and good rotational stability. FLACS might have an impact on optimal postoperative results.

Comparison of the Visual Outcomes of an Extended Depth-of-Focus Lens and a Trifocal Lens

Purpose

To compare the visual performance of the AcrySof IQ PanOptix trifocal intraocular lens and the TECNIS Symfony extended depth-of-focus lens at near and distance visual ranges.

Methods

A total of 146 patients (221 eyes) who underwent phacoemulsification and cataract extraction and received either a PanOptix or Symfony lens from January 2019 to July 2020 were included in the study (83 PanOptix non-toric, 30 PanOptix toric, 70 Symfony non-toric, and 38 Symfony toric). Uncorrected distance (UDVA), uncorrected near (UNVA), and corrected distance (CDVA) visual acuity were assessed at one-day, one-month, and three-months postoperatively. Averages of UDVA, UNVA, and CDVA were taken to evaluate which lens was superior at near and distance visual ranges. Secondary outcome measures including glare, halo, dryness, and problems with night vision were documented at each postoperative visit.

Results

At one month postoperatively, the average UNVA was 0.16 ± 0.14 logMAR in the PanOptix group and 0.21 ± 0.14 logMAR in the Symfony group (P=0.007); the average UDVA for the PanOptix group was 0.09 ± 0.13 logMAR compared to the Symfony group at 0.10 ± 0.14 logMAR (P=0.67); and the average CDVA was 0.02 ± 0.05 logMAR in the PanOptix group and 0.00 ± 0.04 logMAR in the Symfony group (P=0.11). At three months postoperatively, there were no statistically significant differences in UNVA, UDVA, or CDVA between the two groups (P=0.18, 0.79, 0.68 respectively). There was no statistically significant difference in secondary outcome measures at one- and three-months (P=0.49, 0.10 respectively).

Conclusion

The AcrySof IQ PanOptix trifocal intraocular lens appears to afford better UNVA compared to the TECNIS Symfony extended depth-of-focus intraocular lens at one-month postoperatively, though this difference was not seen at three months postoperatively. There is no statistically significant difference in UDVA and CDVA between the two groups at postoperative day one, one-month, and three-months.

Tolerance to Residual Refractive Errors After Trifocal and Trifocal Toric Intraocular Lens Implantation

OBJECTIVE

The objective of this study was to assess the impact of 0.50 diopter (D) positive or negative defocus on visual function in patients implanted with trifocal and trifocal toric intraocular lenses (IOLs).

METHODS

The study included patients implanted with the AcrySof IQ PanOptix IOL or the PanOptix Toric. Visual acuity (VA) at high (100%), medium (50%) and low (10%) contrast, contrast sensitivity function (CSF), and halo perception were assessed three months after surgery. Explorations were performed with corrected distance visual acuity (CDVA), with a positive defocus of +0.50D (myopization) and with a negative defocus of -0.50D (hyperopization).

RESULTS

The study included 60 eyes of 60 patients (30 eyes with PanOptix and 30 eyes with PanOptix Toric). For both groups, VA was better for all contrast settings at the CDVA situation (P<0.05 in all cases). For low spatial frequencies, no differences in CSF were found among the three refractive situations in either group. For higher frequencies, the results showed an overall trend for better CSF results for the CDVA situation. The halo effect was lower for the CDVA situation if compared to myopization and hyperopization in both the PanOptix and the PanOptix Toric groups (P<0.05 for all cases).

CONCLUSIONS

There is an impact on visual quality and halo perception in patients implanted with trifocal or trifocal toric IOLs even for low residual refractive errors.

Effect of defocus combined with rotation on the optical performance of trifocal toric IOLs

PURPOSE

To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced.

METHODS

This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D).

RESULTS

The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively.

CONCLUSION

For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

Rotation Characteristics of Three Toric Monofocal Intraocular Lenses

Purpose

To evaluate the rotational stability of the three monofocal toric intraocular lenses (IOLs) via data from an online toric IOL back-calculator.

Methods

A retrospective data review of an online toric IOL back-calculator, which allows users to input preoperative toric planning information, postoperative lens orientation, and subjective refraction. Inputted data were used to determine the optimal orientation of the toric IOL to minimize residual refractive astigmatism. Aggregate data from 3/11/2019 to 3/10/2020 were extracted and validated. Only data with ≥0.5D of residual refractive astigmatism were used in the study. Pre-operative intended IOL orientation and post-operative IOL orientation were used to calculate IOL rotation.

Results

After validation, 5397 entries were determined to represent patient eyes, of which 3238 represented the three monofocal IOLs evaluated. The rate of rotation for AcrySof, TECNIS, and enVista Toric IOLs was 72.7%, 83.4%, and 83.0%, respectively, and location only significantly impacted TECNIS IOLs. The magnitude of rotation for rotated IOLs was similar for all models and was significantly more for IOLs initially placed in the oblique axis. All IOL models tended to rotate in a counterclockwise direction (53.2%, 73.0%, 69.7%, respectively; p<0.05), and the tendency was greater for IOLs initially located horizontally.

Conclusion

The AcrySof IQ Toric IOL was more rotationally stable than both the TECNIS and enVista Toric IOLs; there was no significant difference in rotational stability of the latter two.

Comparison of Long-Term Rotational Stability of Three Commonly Implanted Intraocular Lenses

PURPOSE

To compare rotational stability and its influencing factors in 3 different widely used hydrophobic acrylic intraocular lenses (IOLs) from the end of surgery (EoS) to 4-7 months (6 months) in over 380 eyes.

DESIGN

Prospective interventional comparative clinical study.

METHODS

Setting: Department of Ophthalmology, Medical University of Vienna.

PATIENT POPULATION

A total of 381 eyes of 199 patients with age-related cataract received an IOL Acrysof SN60WF, Tecnis ZCB00, or Envista MX60 in a consecutive order.

INTERVENTION

Implantation of an Acrysof, Tecnis, or Envista IOL randomized to the 0 ± 10, 45 ± 10, 90 ± 10, or 135 ± 10° axis in 1 or both eyes. Baseline measurement was performed with patients supine still on the operating table. Postoperative follow-ups were conducted after 1 hour, 1 week, 1 month, and 6 months.

MAIN OUTCOME MEASURES

Difference of absolute rotation from the EoS to 6 months.

RESULTS

Absolute rotations from the EoS to 6 months were 1.65 ± 2.1, 2.65 ± 4.1, and 3.18 ± 5.8° for the Acrysof, Tecnis, and Envista group, respectively. Rotational stability was statistically significantly superior in the Acrysof compared with the Envista group (P = .014), but not compared with the Tecnis group (P = .10). No significant difference was found between the Tecnis and Envista groups (P = .761). Maximum values of 15.8, 38.6, and 44.9° were observed for the Acrysof, Tecnis, and Envista group, respectively.

CONCLUSION

The Acrysof IOL showed the least amount of absolute rotation compared with the Tecnis and Envista IOLs. Outliers possibly requiring secondary intervention were observed in all groups. The amount of rotation was greatest during the first postoperative hour.

Prospective assessment of plate-haptic rotationally asymmetric multifocal toric intraocular lens with near addition of + 1.5 diopters

Background

To prospectively evaluate surgical results following implantation of rotationally asymmetric, plate-haptic, refractive segmented multifocal toric intraocular lenses (IOLs) with near addition of + 1.5 diopters (D) (Lentis Comfort LS-313 MF15T, Oculentis GmbH).

Methods

In 59 eyes of 41 patients, ocular examinations were conducted before and 1 day, 1 week, 1, 3, and 6 months after surgery. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity, uncorrected (UIVA) and distance-corrected (DCIVA) intermediate visual acuity at 70 cm, and uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuity at 30 cm were tested. A defocus curve was drawn, and the degree of disturbing photic phenomena were questioned.

Results

The IOL showed excellent rotational stability; the average absolute rotation was 1.66 ± 1.17 degrees from 1 day 1 to 6 months postoperatively, and 98.1 and 100% of eyes yielded rotation of less than 5 and 10 degrees, respectively. Postoperative distance and intermediate visual acuity were highly satisfactory; UDVA, CDVA, UIVA, and DCIVA were about 20/20, 20/16, 20/25, 20/25, respectively. Near visual acuity was suboptimal; UNVA and DCNVA were at approximately 20/60. The defocus curve analysis showed that 20/25 and 20/40 uncorrected visual acuity was attained at as close as 60 and 40 cm, respectively. Contrast sensitivity was within a normal range, and subjective photic phenomena were minimum.

Conclusions

The refractive segmented, rotationally asymmetric multifocal toric IOLs with + 1.5 D near addition showed superb rotational stability and highly satisfactory distance and intermediate vision. Contrast sensitivity was high and incidence of photic symptoms was very low.

Trial registration

This study was registered at JAPIC Clinical Trials Information, ID: JapicCTI-183,877, https://www.clinicaltrials.jp/cti-user/trial/Search.jsp (February 5, 2018).

Effect of haptic geometry in C-loop intraocular lenses on optical quality

The biomechanical stability of intraocular lenses (IOLs) must achieve high-quality optical performance and clinical outcomes after cataract surgery. For this reason, the quality and performance features of the IOLs should be previously analysed following the Standard ISO 11979-2 and ISO 11979-3. The ISO 11979-3 tries to reproduce the behaviour of the IOL in the capsular bag by compressing the lens between two clamps. With this test, it has been demonstrated that the haptic design is a crucial factor to obtain biomechanical stability. Hence, the main goal of this study was to design an aberration-free aspheric IOL and to study the influence of haptic geometry on the optical quality. For that purpose, 5 hydrophobic IOLs with different haptic design were manufactured and their biomechanical stability was compared experimentally and numerically. The IOLs were classified as stiff and flexible designs depending on their haptic geometry. The biomechanical response was measured by means of the compression force, the axial displacement, the angle of contact or contact area, the decentration, the tilt and the strain energy. The results suggest that in vitro and in silico compression tests present similar responses for the IOLs analysed. Furthermore, the flexible IOL designs presented better biomechanical stability than stiff designs. These results were correlated with the optical performance, where the optical quality decreases with worst biomechanical stability. This numerical methodology provides an indisputable advance regarding IOL designs, leading to reduce costs by exploring a feasible space of solutions during the product design process and prior to manufacturing.

Optical tolerance to rotation of trifocal toric intraocular lenses as a function of the cylinder power

BACKGROUND

The aim was to assess the impact of 5- and 10-degree rotations in the optical quality of a trifocal toric intraocular lens with different amounts of cylinder.

METHODS

Two Physiol Toric intraocular lenses with 1.5 and 3.0 D of cylinder were analysed in three different positions: centred, 5 and 10 degrees rotated. The optical quality of the intraocular lenses was evaluated with the PMTF optical bench through specific perpendicular targets. The analysis was performed by the through-focus modulation transfer function curves and the modulation transfer function corresponding to distance vision (0 D of vergence).

RESULTS

For a centred situation, the through-focus modulation transfer function curves of both intraocular lenses showed the classical three peaks corresponding to the powers of the two principal meridians of the intraocular lenses. When 5 and 10 degrees of rotation were induced, the three peaks were attenuated in both cases. The case with the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation showed the worst optical quality and a significant loss of trifocality. The modulation transfer function values obtained for distance vision also showed the worst optical quality for the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation.

CONCLUSION

Rotations over 5 degrees decreased the optical quality of trifocal toric intraocular lenses, being this reduction moderate from 5 to 10 degrees for low levels of cylinder (≤1.5 D). For mid-high levels of cylinder (≥3.0 D), rotations over 5 degrees cause a significant loss of optical quality at all object distances.

Accuracy of two devices and three different calculation methods for predicting residual astigmatism after intraocular lens implantation

This study examined how different methods of biometric measurement, types of intraocular lens calculation, and levels of surgeon experience affected predicted postoperative astigmatism with toric intraocular lens implantation. The error in predicted residual astigmatism was determined using the IOL Master 500 and Lenstar LS 900 devices and was calculated by the Alcon toric calculator, Alcon toric calculator with Baylor nomogram, and Barrett toric calculator. Results were reviewed from 147 eyes of 125 patients. Of the three calculations, the Barrett toric calculator had the lowest mean absolute error in predicted residual astigmatism (P < 0.0001). The mean absolute errors of the IOL Master 500 and the Lenstar LS 900 were not significantly different when compared using three different calculation methods (P = 0.54). The mean absolute error was significantly lower (P = 0.049) for ophthalmology staff than for ophthalmology residents when calculation methods were considered. In conclusion, the calculation method used for IOL selection in cataract surgery significantly affects the accuracy of both staff and residents.

Evaluating Refractive and Visual Outcomes After Bilateral Implantation of an Apodized Diffractive Multifocal Toric Intraocular Lens with a Moderate Add in the Dominant Eye and a Higher Add in the Fellow Eye

Purpose

To review refractive, visual acuity, defocus curve and subjective visual quality results after bilateral implantation of an apodized diffractive toric intraocular lens (IOL) with a moderate add in the dominant eye and a higher add in the non-dominant eye.

Setting

One site in Gainesville, GA, USA.

Design

Single arm, non-randomized prospective study.

Methods

This was a single-arm prospective study of visual acuity and subjective visual quality after implantation of a toric low-add apodized diffractive multifocal IOL in the dominant eye and a higher add IOL of the same type in the non-dominant eye three months after surgery. Binocular visual acuity at 4 m, 60 cm and 40 cm was tested. Other tests included refraction, defocus curve measurement and evaluation of the quality of vision. Toric IOL orientation was also measured.

Results

A total of 29 subjects were enrolled. There were no statistically significant differences in the mean keratometry, corneal astigmatism or IOL sphere power implanted in the dominant and non-dominant eyes. Vision was preferred without any correction in more than half of the eyes tested (32/58, 55%). The residual refractive astigmatism was ≤ 0.50 D in 100% of eyes. Seventy-five percent of subjects (22/29) had 0.10 logMAR (20/25 Snellen) binocular uncorrected visual acuity at all tested distances. Glare and haloes were the most common visual disturbances, but most subjects (22/29, 76%) reported that they were not bothered by any visual disturbances. In 97% of eyes (56/58), the measured difference in orientation between 1 month and 3 months was less than 5 degrees, with no change more than 14 degrees.

Conclusion

This blended bifocal IOL modality appears to be well-tolerated by subjects with a good range of vision and minimal bother from visual disturbances.

Systematic Study on the Biomechanical Stability of C-Loop Intraocular Lenses: Approach to an Optimal Design of the Haptics

To study the main design parameters that affect the mechanical stability of C-loop intraocular lenses, leading to an optimal design that minimizes the axial displacement, tilt and rotation. A total of 144 geometrical variations were studied on a 1-piece, non-angulated, C-loop hydrophobic acrylate intraocular lens. The study was performed in a finite element modeling simulation. The suitable set of variations was determined using a mixed-factorial analysis, allowing to analyse the impact of the different designs on the mechanical stability of the lens (compression force, axial displacement, tilt and rotation). The design parameters under study were: the length, width, thickness and opening angle of the haptic, the haptic-optic junction and the start of the haptic curvature. The compression (or reaction) force is affected by the haptic width, the haptic-optic junction, and the interaction between both. The axial displacement is mainly affected by the width and thickness of the haptic, and the size of the haptic-optic junction as well. The tilt is affected by the haptic thickness and the interaction between the haptic curvature and the haptic-optic junction. The rotation is affected by the start of the haptic curvature, the haptic-optic junction and the haptic width. The haptic-optic juntion is one of the most influential parameters affecting the four responses studied of the C-Loop IOL. The smaller the haptic-optic juntion, the better biomechanical stability.

Refractive and Visual Outcomes and Rotational Stability of Toric Intraocular Lenses in Eyes With and Without Previous Ocular Surgeries: A Longitudinal Study

PURPOSE

To evaluate visual and refractive outcomes and rotational stability of toric intraocular lens (IOL) implantation in eyes with previous ocular surgeries.

METHODS

This controlled, longitudinal cohort study included a total of 133 eyes (59 study cases with a history of corneal, vitreoretinal, and/or glaucoma surgery and 74 randomly selected controls without a history of ocular surgery) that had cataract and corneal astigmatism treated with toric IOL implantation. Postoperative outcomes were recorded at postoperative 1 month and 3 to 12 months.

RESULTS

Refractive prediction errors were within ±1.00 diopter (D) of target in 93.5% and 88.4% of the study cases at postoperative 1 month and 3 to 12 months, respectively. They were within ±0.50 D of target in 56.5% and 60.5% of the cases during the same follow-up intervals, respectively. Study cases showed statistically significantly inferior uncorrected distance visual acuity (UDVA) compared to controls at 1 month postoperatively (0.27 ± 0.24 and 0.17 ± 0.21 logMAR, respectively, P = .027) but not during the later follow-up (0.19 ± 0.19 and 0.16 ± 0.19 logMAR, respectively, P = .431). Corrected distance visual acuity (CDVA) was slightly lower in the study cases than in controls at 1 month postoperatively (0.13 ± 0.16 and 0.07 ± 0.14, respectively, P = .005) and subsequent follow-up months (0.10 ± 0.13 and 0.03 ± 0.10, respectively, P < .001). Of the examined study cases, 93.9% and 88.4% had IOL axes within 5° of intended axis at postoperative 1 month and 3 to 12 months, respectively.

CONCLUSIONS

Toric IOLs provided significant and sustained improvement in visual acuity and refraction in eyes with a history of prior ophthalmic surgery. Refractive outcomes achieved postoperatively were comparable to those in eyes without a prior history of ophthalmic surgery, although the rate of visual recovery may be different. [J Refract Surg. 2019;35(12):781-788.].

Visual quality and patient satisfaction with a trifocal intraocular lens and its new toric version

PURPOSE

To assess and compare the visual quality and subjective outcomes of a trifocal spherical intraocular lens (IOL) and its new toric version.

SETTING

Clínica Rementería, Madrid, Spain.

DESIGN

Prospective case series.

METHODS

Patients had bilateral implantation of the AcrySof IQ PanOptix spherical or toric IOL. Three months postoperatively, monocular and the binocular uncorrected and corrected distance, intermediate, and near visual acuities; binocular defocus curves; and binocular contrast sensitivity function (CSF) were assessed. Patient satisfaction was evaluated with the Catquest 9SF questionnaire.

RESULTS

The study comprised 250 eyes (166 with spherical IOL; 84 with toric IOL) of 125 patients. Both groups had good monocular visual acuity at all distances with no statistically significant differences between groups. The mean monocular uncorrected acuity in the spherical group was 0.06 logarithm of the minimum angle of resolution (logMAR) ± 0.07 (SD), 0.20 ± 0.10 logMAR, and 0.05 ± 0.07 logMAR for far, intermediate, and near, respectively, and in the toric group, 0.07 ± 0.10 logMAR, 0.23 ± 0.20 logMAR, and 0.07 ± 0.12 logMAR, respectively. Defocus curves showed a visual acuity of 0.1 logMAR or better between -2.5 diopters (D) and +0.5 D with no differences between groups. The CSF values were within normal ranges with both IOLs. The questionnaire showed high rates of patient satisfaction with no differences between groups.

CONCLUSIONS

The visual outcomes with the 2 IOLs were similar. With optimum implantation and alignment, the trifocal toric IOL seems to provide visual quality and patient satisfaction that is equivalent to that with the nontoric version with the same platform.

Evaluation of an intraoperative toric intraocular lens alignment system using an image-guided system

PURPOSE

To evaluate an intraoperative toric intraocular lens (IOL) alignment system using a dedicated operating microscope with an image-guided system without preoperative corneal marking.

SETTING

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN

Prospective case series.

METHODS

In this prospective study, a new operating microscope system was used for cataract surgery (toric IOL alignment system of the OPMI Lumera 700 microscope and CALLISTO eye software). This system allows toric IOL alignment by matching limbal vessels from a preoperative photograph with the live image of the microscope. The preoperative photograph was taken with IOLMaster 500, which included a "Reference Image Attachment" system (red-free image), and this was used to track and follow the eye during surgery. After surgery, rotational alignment was assessed and compared with the preoperative axis calculation. At 1 hour postoperatively, a retroilluminaton photograph was taken, and then rotational alignment was compared with the preoperative axis calculation to see the rotational stability.

RESULTS

Fifty eyes of 50 patients were included. The feasibility of the intraoperative marking was high. Deviation between the postoperative (at the end of surgery in the operating room) and aimed IOL axes was 0.52 degrees ± 0.56 (SD). The deviation between 1 hour postoperatively and the aimed IOL axes was 5.10 ± 4.45 degrees.

CONCLUSION

Intraoperative toric IOL alignment using an image-guided system was an accurate and fast procedure resulting in precise toric IOL alignment, and the system simplified the positioning of toric IOLs. There was a slight rotation of IOLs shortly after surgery (within the first hour).

Outcomes of toric supplementary intraocular lenses for residual astigmatic refractive error in pseudophakic eyes

PURPOSE

To evaluate rotational stability and visual and refractive outcomes of supplementary toric IOLs (Sulcoflex Toric 653T, Rayner Intraocular Lenses Ltd) for residual astigmatic refractive error in pseudophakic eyes.

METHODS

A retrospective interventional case series was conducted in a single surgeon practice. Charts of patients who had Sulcoflex Toric supplementary IOLs inserted between June 2009 and September 2015 were reviewed. Outcomes were compared between eyes with and without prior corneal transplant. Patients with at least 3-months follow-up were included.

RESULTS

In 51 eyes, mean UDVA improved from 20/86 to 20/43 (p = 0.002), though UDVA was better in eyes without corneal grafts (20/31) than eyes with (20/62). The proportion of eyes achieving 20/20 UDVA was 43%, 61% and 17% overall, in eyes with prior graft and in eyes with no prior graft, respectively. Sixty-four percentage achieved a spherical equivalent of within 0.5D of target (84% no graft, 34% prior graft). Fifty-three percentage of eyes achieved a cylinder of within 0.5D of target (no graft: 73%, prior graft: 0%). Mean lens rotation was 8.23° on day 1, and mean maximal rotation during follow-up was 17.63°. Sixty-two percentage of IOLs required repositioning. Of those that required repositioning, this was conducted a mean of 2.3 times. The mean final IOL rotation (following repositioning if required) was 6.17°.

CONCLUSION

Sulcoflex Toric supplementary IOLs result in good visual and refractive outcomes in eyes with no prior corneal graft. However, outcomes are sub-optimal in eyes with prior corneal transplantation, and the majority of lenses require repositioning.

Toric intraocular lenses in eyes with with-the-rule, against-the-rule, and oblique astigmatism: One-year results

PURPOSE

To assess 1-year clinical results of toric intraocular lenses (IOLs) in eyes having with-the-rule (WTR), against-the-rule (ATR), or oblique corneal astigmatism.

SETTING

Four ophthalmic surgical sites, Japan.

DESIGN

Prospective case series.

METHODS

One of 3 toric IOLs or 1 nontoric IOL was implanted in eyes having phacoemulsification and IOL implantation.

RESULTS

The study comprised 218 eyes (155 patients). Based on the suggestion of an online toric calculator with anterior corneal curvature data, 63 eyes received the SN6AT3 IOL with a cylinder power of 1.50 diopters [D] at IOL plane (1.50 D cylinder IOL) 55 eyes the SN6AT4 IOL with a cylinder power of 2.25 D at IOL plane (2.25 D cylinder IOL), and 58 eyes the SN6AT5 IOL with a cylinder power of 3.00 D at IOL plane (3.00 D cylinder IOL) (all Acrysof IQ toric), and 42 eyes received the SN60WF IOL (nontoric IOL). One hundred ninety-four eyes (89.0%) completed 1-year of follow-up. The centroid error in predicted residual astigmatism calculated using vector analysis was close to the origin in eyes with WTR astigmatism (0.17 diopter [D] @ 174.9 ± 0.54 D), while those with ATR and oblique astigmatism were significantly shifted toward the ATR direction (P < .001). The distance from the origin was significantly smaller in the WTR group than in ATR and oblique groups (P < .05). The centroid errors were shifted toward ATR in all toric IOL groups (P < .001); however, the distance from the origin was not different between groups (P = .52). Postoperatively, the mean absolute misalignment of the IOLs was 5.92 degrees ± 5.59 (SD) at 1 day and 6.24 ± 5.87 degrees at 1 year. The results of other clinical parameters were excellent, with no significant differences between astigmatism categories or IOL models.

CONCLUSION

Based on anterior corneal curvature alone, toric IOLs undercorrected ATR and oblique astigmatism; however, 1-year clinical results of toric IOLs were highly stable and satisfactory.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Patient outcomes following implantation with a trifocal toric IOL: twelve-month prospective multicentre study

PURPOSE

To evaluate clinical outcomes with a premium diffractive-refractive trifocal toric intraocular lens (IOL) over a 12-month period.

METHODS

Multicentre prospective clinical trial including 227 eyes of 114 patients undergoing cataract surgery with bilateral implantation of the AT LISA tri toric 939MP IOL (Carl Zeiss Meditec, Jena, Germany). One patient was implanted unilaterally. Outcome measures were: visual acuity, manifest refraction, reading performance, contrast sensitivity, defocus curve, patient satisfaction and subjective quality of vision. Alpins vector analysis was used to evaluate astigmatic changes.

RESULTS

12-month follow up results of binocular uncorrected distance, intermediate and near visual acuity were ≤0.3 logMAR in 99.0%, 98.10% and 91.40% of eyes, respectively. 79.7% of eyes had a cylinder value of ±0.50 D at 12 months post-surgery. Contrast sensitivity was in the normal range at 6 months post-surgery. The defocus curve exhibited a smooth transition between far and near foci. Vector analysis showed a mean magnitude of error of -0.16 ± 0.48 D. Mean binocular distance-corrected reading visual acuity was 0.15 ± 0.13 logRAD at 6 months postoperatively. 93.3%, 89.4% and 84.6% of patients expressed satisfaction (good or very good) with distance, intermediate and near vision, respectively, 12 months after surgery. Most (≥95%) patients felt that visual disturbances, including halos, glare, focusing difficulties and depth perception, caused little or no disturbance.

CONCLUSIONS

The diffractive-refractive trifocal toric IOL, AT LISA tri toric 939MP, provides effective distance, intermediate and near visual acuity in eyes with corneal astigmatism. Patient satisfaction was high and 98.1% of patients expressed satisfaction with the IOL implanted.

Prospective multicenter clinical trial to evaluate the safety and effectiveness of a new glistening-free one-piece acrylic toric intraocular lens

Purpose

Glistening formation in the intraocular lens (IOL) optic has the potential to impact quality of vision. The enVista One-Piece Hydrophobic Acrylic Spherical IOL Model MX60 (MX60 IOL) is currently the only US Food and Drug Administration-approved IOL with a label of “no glistenings”. The purpose of this prospective, multicenter, partially randomized, partially controlled, double-masked, pivotal study was to evaluate the safety and effectiveness of the enVista One-Piece Hydrophobic Acrylic MX60T Toric IOL (enVista MX60T Toric IOL).

Patients and methods

Subjects (n=191) were implanted with the enVista MX60T Toric IOL (cylinder powers 1.25, 2.00, or 2.75 D) or the parent MX60 IOL (control). Eyes within the lowest range of corneal astigmatism were randomized to receive either Toric 1.25 D IOL or control IOL in a 1:1 ratio. All subjects with corneal astigmatism requiring 2.00 or 2.75 D cylinder IOLs received toric IOLs. Rotational stability, cylinder reduction, and best-corrected distance visual acuity were primary effectiveness endpoints measured at Visit 4 (120–180 days postoperatively).

Results

Visit 4 mean absolute axis misalignment in the All Toric group was 4.68°±7.33°, and all subjects had ≤5° absolute rotation from Visit 3 to Visit 4. The 1.25 D group had significantly greater improvement in dioptric cylinder reduction (P<0.001), percent cylinder reduction (P<0.001), and mean uncorrected distance visual acuity (P<0.001), compared to control at Visit 4. Most adverse events (AEs) were mild, with no serious AEs in the study eyes. The rates of cumulative AEs through Visit 4 were below International Organization for Standardization (ISO) standard 11979-7 AE rates.

Conclusion

enVista MX60T Toric IOL is safe and effective for patients with preoperative corneal astigmatism undergoing IOL implantation.

Comparing surgically induced astigmatism calculated by means of simulated keratometry versus total corneal refractive power

Purpose:

To evaluate surgically induced astigmatism as computed by means of either simulated keratometry (KSIM) or total corneal refractive power (TCRP) after temporal incisions.

Methods:

Prospective observational study including 36 right eyes undergoing cataract surgery. Astigmatism was measured preoperatively during the 3-month follow-up period using Pentacam. Surgically induced astigmatism was computed considering anterior corneal surface astigmatism at 3 mm with KSIM and considering both corneal surfaces with TCRP from 1 to 8 mm (TCRP3 for 3 mm). The eyes under study were divided into two balanced groups: LOW with KSIM astigmatism <0.90 D and HIGH with KSIM astigmatism ≥0.90 D. Resulting surgically induced astigmatism values were compared across groups and measuring techniques by means of flattening, steepening, and torque analysis.

Results:

Mean surgically induced astigmatism was higher in the HIGH group (0.31 D @ 102°) than in the LOW group (0.04 D @ 16°). The temporal incision resulted in a steepening in the HIGH group of 0.15 D @ 90°, as estimated with KSIM, versus 0.28 D @ 90° with TCRP3, but no significant differences were found for the steepening in the LOW group or for the torque in either group. Differences between KSIM- and TCRP3-based surgically induced astigmatism values were negligible in LOW group.

Conclusion:

Surgically induced astigmatism was considerably higher in the high-astigmatism group and its value was underestimated with the KSIM approach. Eyes having low astigmatism should not be included for computing the surgically induced astigmatism because steepening would be underestimated.

Comparison of the Rotational Stability of Two Toric Intraocular Lenses in 1273 Consecutive Eyes

PURPOSE

To compare the rotational stability of the 2 most commonly used toric intraocular lenses (TIOLs).

DESIGN

Retrospective cohort study in a single private practice.

SUBJECTS

The study included all patients receiving an Acrysof (n = 626) or Tecnis TIOL (n = 647) over an 18-month period from April 2015 to September 2016. Patients were only excluded if their surgery could not be performed using a digital marking system.

METHODS

All patients had cataract surgery performed in the same surgical center with a similar technique. A digital marking system with limbal vessel registration was used to record the axis of the TIOL at the conclusion of surgery. A dilated examination was performed either later on the day of surgery or the next morning, and the postoperative rotation of the 2 TIOL models was compared. Patients who required a return to the operating room for TIOL repositioning were examined to determine risk factors for reoperation and subsequent outcomes.

MAIN OUTCOME MEASURES

The primary outcome measure was the percentage of eyes with TIOL rotation >5 and >10 degrees. The second main outcome was likelihood of requiring return to the operating room to reposition a rotated TIOL.

RESULTS

The Acrysof TIOL was less likely to rotate postoperatively, with 91.9% of eyes rotated ≤5 degrees at the first postoperative check compared with 81.8% of Tecnis TIOL eyes (P < 0.0001). This difference persisted for rotation ≤10 degrees (97.8% Acrysof vs. 93.2% Tecnis, P = 0.0002) and ≤15 degrees (98.6% Acrysof vs. 96.4% Tecnis, P = 0.02). The mean rotation was 2.72 degrees (95% confidence interval 2.35-3.08 degrees) for Acrysof and 3.79 degrees (95% confidence interval 3.36-4.22 degrees) for Tecnis TIOLs (P < 0.05). The Tecnis TIOL showed a strong predisposition to rotate counterclockwise, unlike the Acrysof. More Tecnis TIOL patients required repositioning (3.1% vs. 1.6%), but this did not reach statistical significance (P = 0.10). Refractive outcomes were similar between the 2 groups.

CONCLUSIONS

The Acrysof TIOL showed significantly greater rotational stability than the Tecnis TIOL.

Optimizing outcomes with toric intraocular lenses

Toric intraocular lenses (IOLs) are the procedure of choice to correct corneal astigmatism of 1 D or more in cases undergoing cataract surgery. Comprehensive literature search was performed in MEDLINE using “toric intraocular lenses,” “astigmatism,” and “cataract surgery” as keywords. The outcomes after toric IOL implantation are influenced by numerous factors, right from the preoperative case selection and investigations to accurate intraoperative alignment and postoperative care. Enhanced accuracy of keratometry estimation may be achieved by taking multiple measurements and employing at least two separate devices based on different principles. The importance of posterior corneal curvature is increasingly being recognized in various studies, and newer investigative modalities that account for both the anterior and posterior corneal power are becoming the standard of care. An ideal IOL power calculation formula should take into account the surgically induced astigmatism, the posterior corneal curvature as well as the effective lens position. Conventional manual marking has given way to image-guided systems and intraoperative aberrometry, which provide a mark-less IOL alignment and also aid in planning the incisions, capsulorhexis size, and optimal IOL centration. Postoperative toric IOL misalignment is the major factor responsible for suboptimal visual outcomes after toric IOL implantation. Realignment of the toric IOL is needed in 0.65%–3.3% cases, with more than 10° of rotation from the target axis. Newer toric IOLs have enhanced rotational stability and provide precise visual outcomes with minimal higher order aberrations.

Stability of a Novel Intraocular Lens Design: Comparison of Two Trifocal Lenses

PURPOSE

To compare visual outcomes, rotational stability, and centration in a randomized controlled trial in patients undergoing cataract surgery who were bilaterally implanted with two different trifocal intraocular lenses (IOLs) with a similar optical zone but different haptic shape.

METHODS

Twenty-one patients (42 eyes) with cataract and less than 1.50 D of corneal astigmatism underwent implantation of one FineVision/MicoF IOL in one eye and one POD FineVision IOL in the contralateral eye (PhysIOL, Liège, Belgium) at IOA Madrid Innova Ocular, Madrid, Spain. IOL allocation was random. Outcome measures, all evaluated 3 months postoperatively, included monocular and binocular uncorrected distance (UDVA), corrected distance (CDVA), distance-corrected intermediate (DCIVA), and near (DCNVA) visual acuity (at 80, 40, and 25 cm) under photopic conditions, refraction, IOL centration, haptic rotation, dysphotopsia, objective quality of vision and aberration quantification, patient satisfaction, and spectacle independence.

RESULTS

Three months postoperatively, mean monocular UDVA, CDVA, DCIVA, and DCNVA (40 cm) under photopic conditions were 0.04 ± 0.07, 0.01 ± 0.04, 0.15 ± 0.11, and 0.16 ± 0.08 logMAR for the eyes implanted with the POD FineVision IOL and 0.03 ± 0.05, 0.01 ± 0.02, 0.17 ± 0.12, and 0.14 ± 0.08 logMAR for those receiving the FineVision/MicroF IOL. Moreover, the POD FineVision IOL showed similar centration (P> .05) and better rotational stability (P < .05) than the FineVision/MicroF IOL. Regarding halos, there was a minimal but statistically significant difference, obtaining better results with FineVision/MicroF. Full spectacle independence was reported by all patients.

CONCLUSIONS

This study revealed similar visual outcomes for both trifocal IOLs under test (POD FineVision and FineVision/MicroF). However, the POD FineVision IOL showed better rotational stability, as afforded by its design. [J Refract Surg. 2016;32(6):394-402.].

Intraocular lens alignment methods

PURPOSE OF REVIEW

This article reviews current concepts in intraocular lens alignment strategies to maximize intraocular lens (IOL) positioning.

RECENT FINDINGS

A variety of strategies has been developed to maximize toric IOL position, including preoperative calculators to determine the appropriate IOL power and orientation, intraoperative alignment devices, and postoperative software to determine if IOL rotation would be beneficial for refractive outcomes.

SUMMARY

The combination of using multiple toric IOL calculators and intraoperative alignment devices has improved toric IOL outcomes. The relationship of the posterior corneal power and its effect on outcomes remains to be fully elucidated. Postoperative IOL rotation may be necessary even when the IOL is aligned as planned because of surgically induced astigmatism.

Visual and Refractive Outcomes of a Toric Presbyopia-Correcting Intraocular Lens

Purpose. To evaluate outcomes in astigmatic patients implanted with the Trulign (Bausch + Lomb) toric presbyopia-correcting intraocular lens (IOL) during cataract surgery in a clinical practice setting. Methods. Retrospective study in 40 eyes (31 patients) that underwent cataract extraction and IOL implantation in a procedure using intraoperative wavefront aberrometry guidance (ORA system). Endpoints included uncorrected visual acuity (VA), reduction in refractive cylinder, accuracy to target, axis orientation, and safety. Results. At postoperative month 1, refractive cylinder was ≤0.50 D in 97.5% of eyes (≤1.00 D in 100%), uncorrected distance VA was 20/25 or better in 95%, uncorrected intermediate VA was 20/25 or better in 95%, and uncorrected near VA was 20/40 (J3 equivalent) or better in 92.5%. Manifest refraction spherical equivalent was within 1.00 D of target in 95% of eyes and within 0.50 D in 82.5%. Lens rotation was <5° and best-corrected VA was 20/25 or better in all eyes. Conclusion. The IOL effectively reduced refractive cylinder and provided excellent uncorrected distance and intermediate vision and functional near vision. Refractive predictability and rotational stability were exceptional. Implantation of this toric presbyopia-correcting IOL using ORA intraoperative aberrometry provides excellent refractive and visual outcomes in a standard of care setting.