Limitations of and Solutions to Using 6 mm Corneal Spherical Aberration and Q Value after Laser Refractive Surgery

This study aimed to evaluate the spherical aberration (SA) in different corneal areas before and after femtosecond laser-assisted in situ keratomileusis (fLASIK) and transepithelial photorefractive keratectomy (tPRK), with the goal of identifying the limitations of and potential improvements in using SA within a 6 mm area. The study included 62 patients who underwent fLASIK and tPRK. Complete eye examinations including keratometry, corneal epithelial thickness, central corneal thickness, and topography were performed preoperatively and postoperatively. Anterior, posterior, and total corneal aberrations were measured preoperatively and three months postoperatively, with pupil diameters ranging from 2 to 8 mm. In the fLASIK group, compared to the preoperative SA, the anterior and total SA increased postoperatively in the 6 and 7 mm areas. In the tPRK group, meanwhile, the anterior and total SA of the 5 mm or larger areas increased postoperatively. An area of 6 mm or larger showed an increase in correlation with the changes in Q value and refractive correction. As the corneal SA and asphericity in the 6 mm zone cannot specifically demonstrate the status of areas smaller than 6 mm or changes in the optical zone after laser refractive surgery, comparison with normal values in various areas of the cornea is necessary.

Comparative Analysis of the Visual, Refractive and Aberrometric Outcome with the Use of 2 Intraocular Refractive Segment Multifocal Lenses

To demonstrate the results of ray tracing higher- and lower-order aberrations in pseudophakic eyes with rotationally asymmetrical segment multifocal lenses, total high- and low-order aberrations, measured by root mean square value (RMS), refraction, uncorrected distance and uncorrected near visual acuity (UCDVA and UCNVA), and tear break-up time, were measured at scotopic size in 42 eyes of patients implanted with bifocal refractive Mplus15/Mplus30 IOL with +1.5 dpt near addition (42 eyes of patients implanted with Mplus15)/+3.0 dpt near addition (91 eyes of patients implanted with Mplus30), and 107 eyes of control group. No significant differences were noticed between the examined groups concerning UCDVA, UCNVA, and tear break-up time (p < 0.001). Coma and total high-order aberrations were significantly higher for the Mplus30 lens in comparison to the Mplus15 lens and the control group (Coma, Trefoil p < 0.001, Secondary Astigmatism p = 0.002). The spherical aberrations were significantly higher in the lower-addition lens (p = 0.016) in comparison to the control group and to the higher-addition lens group (p < 0.001). Both intraocular lens models were successful at reaching refractive aim, good distance, and near function with the lower higher-order aberrations for the low-addition lens.

Visual Outcomes, Quality of Vision, Patient Satisfaction and Spectacle Independence After Bilateral Implantation of the Synergy™ Intraocular Lens

Purpose

To evaluate vision, visual quality, patient satisfaction and spectacle independence after bilateral implantation of the TECNIS Synergy™ intraocular lens.

Setting

Two clinical practices in the USA.

Design

Ambispective unmasked non-randomized clinical trial.

Methods

Patients with a history of uneventful bilateral femtosecond laser assisted cataract surgery with the study IOL implanted, targeted for emmetropia, at least 3 months prior to the study visit were enrolled. Monocular and binocular visual acuity (VA) were measured at distance, intermediate and near, along with binocular mesopic VA. Low contrast binocular VA and reading speed in mesopic and photopic conditions were also measured. Patient satisfaction, spectacle independence, visual symptoms, and functional vision questionnaires were completed.

Results

Results from 52 subjects were available for analysis. Mean binocular unaided visual acuity was ~0.1 logMAR (20/20) from distance to 33 cm, with 81% of subjects having 0.2 logMAR (20/25) vision or better at all test distances and 92% reporting never needing glasses at any distance. Average reading speed at 40 cm was only 10 words/minute slower in dim light (p = 0.03). Mesopic and low contrast acuity appeared good. Halos were the most frequent and bothersome visual disturbances, with the greatest effect on driving at night. Eighty-eight percent of subjects reported being "completely" or "mostly" satisfied with their overall unaided vision.

Conclusion

This hybrid technology IOL provided a range of binocular visual acuity from distance to 33 cm and good functional vision, even in dim light. Patients should be advised of the likelihood of visual disturbances, particularly halos.

Assessing Visual Outcomes: A Comparative Study of US-FDA Premarket Approval Data for Multifocal and EDOF Lens Implants in Cataract Surgery

This study compares the efficacy, safety, and patient-reported outcomes of three intraocular implants (IOL): Tecnis Synergy IOL, AcrySof IQ PanOptix Trifocal, and Tecnis Symfony EDOF IOL. Participants achieving 20/20 or better uncorrected binocular visual acuity were as follows: Synergy-67% distance, 64% intermediate, and 47% near; PanOptix-73% distance, 73% intermediate, and 50% near; and Symfony-63% distance, 75% intermediate, and 22% near. Symfony demonstrated superior intermediate visual acuity compared to Synergy (p = 0.0182) for those achieving 20/25 or better. Both Synergy and PanOptix showed superiority over Symfony for near visual acuity (p < 0.0001). Halos were statistically more common in Synergy participants compared to PanOptix (p = 0.0013) and Symfony (p < 0.0001). Each trial lens outperformed its monofocal IOL in terms of independence from glasses or contacts, with Synergy and PanOptix showing statistical significance over Symfony. Comparing contrast sensitivities and defocus curves was challenging due to data variance and as such, standardization of United States Food and Drug Administration (US-FDA) data reporting is key for better comparison of outcomes among different IOL platforms.

How Reliable Is Pyramidal Wavefront-Based Sensor Aberrometry in Measuring the In Vivo Optical Behaviour of Multifocal IOLs?

Cataract or refractive lens surgery, along with the implantation of multifocal intraocular lenses (MF-IOL), enables a complete range of functional far, near and intermediate vision. Refractive, diffractive and extended depth of focus (EDoF) or combination of these principles represent the technology used to obtain this multifocality. Aberrometry makes it possible to study the aberrations induced by MF-IOLs. Among the different optical principles available to measure ocular aberrations, pyramidal wavefront-based sensor (PWS) aberrometry shows the highest resolution with MF-IOLs. Retinal image quality measured by a PWS aberrometer differed significantly according to the technology of the implanted lens. Monofocal and diffractive lenses showed the highest values of far-distance retinal image quality, followed by refractive and EDoF lenses; however, retinal image quality analysed in diffractive lenses appears to be more dependent on residual refractive error. Considering this limitation, PWS-aberrometry could be used to compare diffractive lenses. Nevertheless, further studies are needed to provide additional information about the clinical retinal image quality of MF-IOLs and to help surgeons in the important preoperative selection of IOLs.

Measurement of change in angle kappa and its correlation with ocular biometric parameters pre- and post-phacoemulsification

Purpose

Angle kappa has been considered to play a role in causing glare and haloes despite accurate centration during implantation of multifocal intraocular lenses following phacoemulsification. There is a lack of substantial data regarding whether angle kappa is a constant entity or changes following ocular surgical procedures. To answer this question, in this prospective observational study, we measured change in angle kappa following phacoemulsification, and studied the ocular biometric parameters correlating with this change.

Methods

Angle kappa was measured objectively using synoptophore. Ocular Biometric parameters (Anterior Chamber Depth, Corneal White-to-White measurement, Lens Thickness, and Axial Length) using LenStar LS 900 Haag Streit Anterior Segment imaging system. outcome measures were a quantitative change in angle kappa from the preoperative value by one degree or more and observation of correlation between change in angle kappa and ocular biometric parameters. The Wilcoxin Signed Rank Test was used to determine the difference between pre-operative and post-operative measurements for angle kappa. A p-value of less than 0.05 was considered statistically significant. Pearson's correlation coefficient was employed to find the relationship between preoperative ocular biometric parameters and a change in angle kappa. A linear regression model was used to derive an equation considering corneal white-to-white measurement as the predictor and change in angle kappa as the outcome measure.

Results

A significant change in angle kappa was recorded, and a significant correlation was found with corneal white to white measurements. This change could be predicted preoperatively, for a known corneal white to white measurement using the standard equation y=mx+c.

Conclusion

This study explains the possible cause of dissatisfaction among seemingly ideal patients who undergo multifocal IOL implantation and the potential for better decision-making during patient selection for multifocal IOL implantation.

Comparative Visual Outcome Analysis of a Diffractive Multifocal Intraocular Lens and a New Diffractive Multifocal Lens with Extended Depth of Focus

This study compares the visual and refractive performance of the TECNIS Synergy (DFR00V-DFW150-225-300-375) multifocal intraocular lens (IOL) and the AcrySof IQ PanOptix (TFAT00-30-40-50-60) multifocal IOL. Patients who underwent phacoemulsification and cataract extraction and received either a multifocal Synergy or PanOptix IOL were included. Monocular uncorrected distance (UDVA), intermediate (UIVA), near (UNVA), and corrected distance (CDVA) visual acuities were assessed at three and six months postoperatively. Secondary outcome measures of photic phenomena were also assessed. A total of 140 patients (224 eyes) were included in this study, with 69 patients (105 eyes) in the Synergy group and 71 patients (119 eyes) in the PanOptix group. There were no statistically significant differences in UIVA or CDVA measurements across all time points. When assessing UDVA, at three months postoperatively, there were more eyes in the PanOptix group with vision better than 20/40 (p = 0.04). At three and six months postoperatively, the average UNVA was superior in the Synergy group (p = 0.01, 0.002). While the Synergy group reported more night vision disturbances at one and three months (p = 0.01, 0.03), the PanOptix group had more night vision disturbances at six months (p = 0.02). Although not statistically significant, the AcrySof IQ PanOptix multifocal IOL demonstrated better UDVA and UIVA sooner postoperatively than the TECNIS Synergy multifocal IOL. The Synergy IOL provided statistically better UNVA compared to the PanOptix IOL at three and six months postoperatively. Synergy patients reported more early photic phenomena than PanOptix patients, which later diminished.

Early patient-reported outcomes of cataract surgery with implantation of the trifocal liberty 677MY intraocular lens: A pilot study

PURPOSE

To report our first clinical and patient-reported outcomes in the early postoperative period with a new model of trifocal diffractive intraocular lens (IOL).

METHODS

Pilot prospective analysis of the results of 26 eyes of 13 patients (age, 44-79 years) undergoing cataract surgery with implantation of the trifocal diffractive IOL Liberty 677MY (Medicontur Medical Engineering Ltd., Zsámbék, Hungary). The following clinical outcomes were evaluated during the first postoperative month: measurement of distance, intermediate and near visual acuity, binocular defocus curve, and level of spectacle independence, patient satisfaction, perception of photic phenomena, and difficulty in performing several vision-related daily tasks by means of a questionnaire.

RESULTS

Mean binocular LogMAR uncorrected distance, intermediate and near visual acuities were -0.03 ± 0.13, 0.21 ± 0.16, and 0.16 ± 0.09, respectively. Furthermore, 100.0%, 84.6% and 92.3% of patients achieved a binocular corrected distance, distance-corrected intermediate and distance-corrected near visual acuity of 20/32 or better, respectively. In the defocus curve, visual acuities were better than 0.2 logMAR for defocus levels between +1.00 and -3.00 D. Spectacle independence was referred by all patients, with any of them reporting dissatisfaction with the outcome of the surgery. The postoperative vision did not lead to difficulties in the daily life in 92.3% of patients. Bothersome halos, glare or starbursts were only reported by only 7.7% of patients.

CONCLUSIONS

The trifocal IOL evaluated provides a successful visual rehabilitation with minimal photic phenomena associated, leading to high levels of spectacle independence and patient satisfaction.

Premium intraocular lenses in children

Multifocal and toric intraocular lenses (IOLs) or the so-called premium IOLs are currently widely used in adult patients as a one-step refractive solution following cataract surgery. However, the decision to implant a premium IOL in a pediatric patient involves multiple factors affecting the child's visual development and is associated with several dilemmas and surgical challenges. The purpose of this review is to summarize these factors and analyse the influence of each of them on the visual outcomes following premium IOL implantation. A review of literature was conducted using the relevant keywords from various databases until 31^st January 2022. All pertinent studies with multifocal or toric IOL implantation in children were reviewed, and relevant articles were studied in detail for age, IOL power calculation, visual outcomes (refractive outcomes, contrast sensitivity and stereopsis) and complications such as dysphotic phenomena and others. A total of 17 relevant studies (10 case series/interventional studies and 7 case reports) on the subject were included. All studies showed a favourable refractive outcome; however, the data available was significantly less. Studies with earlier models of multifocal IOLs showed a higher incidence of IOL decentration and posterior capsule opacification; however, more recent studies with newer IOL models showed much better safety profiles. Toric IOLs showed promising results in all the studies evaluated. Premium IOLs have shown promising results in the pediatric age group. However, their long-term outcomes specifically concerning refractive shift, capsular contraction and role in the management of amblyopia needs to be explored further.

The Influence of Angle Alpha, Angle Kappa, and Optical Aberrations on Visual Outcomes after the Implantation of a High-Addition Trifocal IOL

The aim of our investigation was to examine the possible correlations between optical aberrations, angle kappa, angle alpha, and visual outcomes following cataract surgery. In total, 56 eyes of 28 patients were implanted with the Liberty 677MY trifocal intraocular lens (IOL). Pre- and postoperative higher-order aberrations, coma, astigmatism, angle alpha, and angle kappa were registered, along with uncorrected and corrected visual acuities at multiple distances. Visual acuity and contrast sensitivity defocus curves were plotted, and the areas under the curve were calculated 1 and 3 months postoperatively. Excellent visual outcomes were found at all distances. Patients reported low levels of dysphotopsia, and 96.4% of patients achieved complete spectacle independence. While angle kappa significantly decreased during cataract surgery (p = 0.0007), angle alpha remained unchanged (p = 0.5158). Angle alpha correlated with postoperative HOAs and had a negative impact on near vision (p = 0.0543). Preoperative corneal HOA and coma had a strong adverse effect on future intermediate and near vision. Residual astigmatism significantly affected postoperative intermediate vision (p = 0.0091). Our results suggest that angle kappa is not an optimal predictive factor for future visual outcomes, while angle alpha and the preoperative screening of optical aberrations might help patient selection prior to multifocal IOL implantation.

Preliminary Evaluation of the Clinical Benefit of a Novel Visual Rehabilitation Program in Patients Implanted with Trifocal Diffractive Intraocular Lenses: A Blinded Randomized Placebo-Controlled Clinical Trial

The authors of this study evaluated the potential benefit on visual performance of a novel 3 week visual rehabilitation program based on the use of Gabor patches in patients undergoing bilateral cataract surgery with the implantation of two models of trifocal diffractive intraocular lens (IOL). A total of 30 patients were randomly assigned to two groups: a study group (15 patients) that used a videogame based on Gabor patches and a placebo group (15 patients) that used a videogame without specific stimuli for improving visual performance. No statistically significant differences between groups were found in distance, intermediate, and near post-training visual acuity (p ≥ 0.15). Significantly better distance contrast sensitivity (CS) was found for the spatial frequencies of 6 (p = 0.02) and 12 cpd (p = 0.01) in the study group. Likewise, significantly better values of near CS were found in the study group compared to the placebo group for the spatial frequency of 1.5 cpd (p = 0.02). In conclusion, a 3 week visual rehabilitation program based on the use of Gabor patches in the immediate postoperative period after the bilateral implantation of trifocal diffractive IOLs seems to be beneficial for improving both distance and near visual performance achieved with the implant.

Bilateral Implantation of a New Refractive Multi-Segmented Multifocal Intraocular Lens in Cataract or Refractive Lens Exchange Patients

Purpose

To evaluate the safety and efficacy of a new multi-segmented refractive multifocal intraocular lens (IOL) after phacoemulsification and refractive lens exchange (RLE).

Patients and Methods

In this prospective, multicenter clinical trial, 63 presbyopic subjects who had cataract or where RLE candidates were bilaterally implanted with the Precizon Presbyopia IOL (Ophtec BV, Groningen, the Netherlands) after phacoemulsification. The study was conducted at 6 clinical centers in Germany, the Netherlands, Belgium, Turkey and Spain. Subjects were evaluated at baseline and at 1 day, 1 week, 1 and 3 months postoperatively for monocular and binocular uncorrected (UDVA) and corrected distance visual acuity (CDVA), uncorrected (UIVA) and distance-corrected intermediate visual acuity (DCIVA), uncorrected (UNVA), corrected (CNVA) and distance-corrected near visual acuity (DCNVA), contrast sensitivity and quality of vision.

Results

Three months postoperatively, binocular UDVA and CDVA of ≥20/40 was achieved in 98.4% (60/61) and 100%, respectively. Binocular UIVA and DCIVA of ≥20/40 was achieved in 96.7% (59/61) and 93.4% (57/61) respectively. Binocular UNVA, CNVA and DCNVA of ≥20/40 was achieved in 93.4% (57/61), 98.4% (60/61) and 95% (57/60) subjects, respectively. Complete spectacle independence was achieved in 80% (49/61) patients; 93% of patients reported that they were quite or very satisfied with the outcomes of the procedure.

Conclusion

Precizon Presbyopia IOL implantation is a safe and effective method to provide good visual acuity at all distances in presbyopic and cataract patients.

Differences in Visual Working and Mobile Phone Usage Distance according to the Job Profile

PURPOSE

To analyze and characterize the pattern of visual working distance (WD) and mobile phone usage distance (MPD) in a large population, analyzing the differences in these parameters according to the job profile.

METHODS

Cross-sectional study consisting of a screening campaign evaluating the visual status of professionals from seven different environments. A total of 454 participants with a mean age of 41.5 years (range, 22-64 years) were revised. The screening campaign consisted of several rapid tests performed in a single session in the usual work environment of each participant, including measurement of WD, arm length, and MPD (VisionApp, VisionApp Solutions S.L.).

RESULTS

WD was significantly longer than MPD (82.5 ± 150.6 vs. 31.9 ± 6.3 cm, p < .001), whereas no significant differences were found between arm length (74.3 ± 4.8 cm) and WD (p = .493). WD was below 80 cm in 89.6% (407/454) of participants, whereas MPD was below 40 cm in 89.0% (404/454). No significant correlation was found between WD and MPD (r = 0.126, p = .117). Statistically significant differences were detected among job profile subgroups in WD (p < .001), with military personnel showing significantly longer WD than other professionals (p ≤ 0.018). Significant differences were also found between job profile subgroups in MPD (p = .006), with shorter MPDs for shoe factory professionals compared to sellers (p = .046).

CONCLUSIONS

WD and MPD vary significantly among individuals, but always showing a shorter MPD. WD varies significantly also according to the job profile, being necessary to consider this information when selecting the most optimal optical aid in each case, especially for the compensation of presbyopia.

A clinical study to assess feasibility, acceptance, and outcome of multifocal intraocular lens in patients with bilateral immature cataract at a tertiary eye care institute

Purpose

: To assess feasibility, acceptability, and outcome of multifocal intraocular lenses (IOL) in patients with bilateral immature cataract.

Methods

1691 patients with bilateral immature cataract were included in the study. The feasibility of these IOLs was calculated by studying ocular parameters using Visionix VX120 and subjective characteristics. A prospective study was then conducted in 148 eyes of 74 patients in which multifocal IOLs were implanted. Their visual outcome was assessed using LogMAR for distance and Snellen's chart for near vision, contrast sensitivity by Pelli-Robson chart, and satisfaction using visual function-7 questionnaire.

Results

Considering ocular and subjective characteristics, it was feasible to implant the lens in 920 patients (54.40%) and the acceptability rate was 8.04%, most common reason for decreased acceptability was cost (85%) of IOL. The median distance uncorrected visual acuity (UCVA) at day 7 and at 30 days was LogMAR 0.2 (0.1-0.3) and 0.15 (0.1-0.2), respectively, which was statistically significant compared to preoperative distance UCVA (P < 0.001). The median near UCVA at day 7 and 30 days was N6 for both and statistically significant (P < 0.001) compared to preoperative near UCVA. 77.02% patients had distance UCVA of LogMAR (0.0-0.2) and 91.8% had near UCVA of N6-N8 at 30 days. The contrast sensitivity was decreased in all patients.

Conclusion

Appropriately selected patients can achieve spectacle independence and good visual satisfaction which begins with proper patient education, lifestyle and personality dynamics, and individualized weighing of benefits and side effects of multifocal IOLs.

Comparison of three different presbyopia-correcting intraocular lenses

Objective (aim): to test the refractive and visual outcomes and the quality of vision after the bilateral implantation of three different multifocal intraocular lenses (MIOLs) in patients with age-related cataract. Methods: In this retrospective, comparative study including 90 eyes of 45 cataract patients, bilateral implantation of either the hydrophilic trifocal Liberty® 677MY capsular bag IOL, the hydrophilic AT LISA® tri 839M lens, or the hydrophobic AcrySof® IQ PanOptix® IOL was performed during routine cataract surgery. Refractive outcomes, visual acuities (VA) for far, intermediate and near distances, as well as visual quality, dysphotopic events and spectacle use were evaluated six months postoperatively. Results: VA curves were similar for the three MIOLs, however the Liberty lens seemed to be superior for far and near, while AT LISA tri provided somewhat better VA in the intermediate range. Refractive correction was the most effective with the Liberty IOL (p=0.0131). Dysphotopic phenomena were usually perceived in low light conditions. Their frequency was lower with the AT LISA tri and Liberty lenses. Symptoms were significantly less disturbing for patients implanted with the Liberty lens, two-thirds of AT LISA tri and Liberty patients, while only 57% of PanOptix patients achieved spectacle independence. Conclusions: All examined MIOLs were found to be safe and efficient in presbyopia-correction of cataract patients, however different models had different advantages. The vision preferences of each patient should always be taken into consideration when choosing a MIOL, and the possible occurrence of dysphotopic events should be also clearly communicated in each case. Abbreviations: ACD = Anterior chamber depth, ANOVA = Analysis of variance, AXL = Axial length, CDVA = Corrected distance visual acuity, CYL = Cylinder; Cylindric refraction, D = Diopter, IOL = Intraocular lens, K1; K2 = Keratometry values, MIOL = Multifocal intraocular lens, n = Number of cases, n.a. = Not applicable, Postop = Postoperative, QoV = Quality of Vision, SD = Standard deviation, SEQ = Spherical equivalent, SPH = Sphere; Spherical refraction, UDVA = Uncorrected distance visual acuity, UIVA = Uncorrected intermediate visual acuity, UNVA = Uncorrected near visual acuity, VA = Visual acuity.

A clinical assessment of visual performance of combining the TECNIS® Symfony Extended Range of Vision IOL (ZXR00) with the +3.25 D TECNIS Multifocal 1-piece IOL (ZLB00) in subjects undergoing bilateral cataract extraction

Purpose

To combine the increased depth of focus of the TECNIS^® Symfony intraocular lens (IOL) with a TECNIS Multifocal (MF) low-add IOL (+3.25) to enable a patient to be less dependent on corrective lenses.

Setting

Clinic in Canada.

Design

Single-center, prospective, open-label.

Materials and methods

Fifty patients were enrolled for bilateral surgery. Patients were implanted with TECNIS Symfony Extended Range of Focus lens in the dominant eye, and TECNIS low-add +3.25 MF IOL in the non-dominant eye. Patients were ≥18 years of age and had best-corrected visual acuity >20/30 in both eyes, pupil size >3.5 mm, and <1.5 D of corneal astigmatism. Patients were evaluated preoperatively, operatively, and postoperatively on Day 1, Day 7, Month 1, and Month 3. Postoperative evaluations at Month 3 were completed by 32 of 50 patients enrolled, and included distance, intermediate and near visual acuity (VA), and subjective outcomes.

Results

Three months postoperatively, binocular results without correction revealed 97% (29/30) of patients had distance VA of 20/20 or better, 97% (29/30) had intermediate VA of 20/25 or better, and 94% (28/30) had near VA of 20/25 or better. At Month 3, the majority of patients reported “none” for visual symptoms of glare (30/30, 100%), halo (29/30, 96.6%), starbursts (29/30), or other – blur (30/30, 100%).

Conclusion

Three months postoperatively, the combination of the increased depth of focus of the TECNIS Symfony IOL with a TECNIS MF low-add (+3.25) IOL may provide excellent uncorrected VA at near, intermediate, and far distances with minimal ocular symptoms.

Comparative study of induced changes in effective lens position and refraction after Nd:YAG laser capsulotomy according to intraocular lens design

Purpose

To evaluate and compare the changes in refraction and effective intraocular lens (IOL) position between a plate-haptic IOL and a c-loop single-piece IOL after neodymium-doped yttrium aluminium garnet (YAG) laser posterior capsulotomy.

Methods

In a prospective study, anterior chamber depth and subjective refraction were measured in 110 pseudophakic eyes from 110 patients, before and 1 month after YAG laser capsulotomy. Patients were divided into 2 groups according to the IOL design: group 1 (plate-haptic acrylic hydrophilic AT LISA tri 839MP^®) and group 2 (c-loop acrylic hydrophobic single-piece AcrySof^® SA60AT). Lens position was obtained through optical coherence biometry (Biograph WaveLight OB820^®).

Results

YAG laser capsulotomy was performed 37.8±9.8 months after surgery in group 1 and 40.6±8.6 months in group 2 (p=0.125). Significant changes were found in the lens effective position after treatment in the 2 groups. The YAG posterior capsulotomy led to a change of anterior chamber depth in group 1 from 4.03±0.32 mm to 3.86±0.34 mm (p=0.02) and in group 2 from 4.03±0.37 mm to 4.14±0.45 mm (p=0.025). After YAG laser posterior capsulotomy, no significant changes were observed in mean spherical equivalent, sphere or cylinder for both groups (p>0.05).

Conclusion

YAG laser posterior capsulotomy can induce a significant change in the IOL position according to the IOL type; however, the refractive change after treatment is clinically insignificant.

Comparison of two laboratory-based systems for evaluation of halos in intraocular lenses

Purpose

Multifocal intraocular lenses (IOLs) can be associated with unwanted visual phenomena, including halos. Predicting potential for halos is desirable when designing new multifocal IOLs. Halo images from 6 IOL models were compared using the Optikos modulation transfer function bench system and a new high dynamic range (HDR) system.

Materials and methods

One monofocal, 1 extended depth of focus, and 4 multifocal IOLs were evaluated. An off-the-shelf optical bench was used to simulate a distant (>50 m) car headlight and record images. A custom HDR system was constructed using an imaging photometer to simulate headlight images and to measure quantitative halo luminance data. A metric was developed to characterize halo luminance properties. Clinical relevance was investigated by correlating halo measurements to visual outcomes questionnaire data.

Results

The Optikos system produced halo images useful for visual comparisons; however, measurements were relative and not quantitative. The HDR halo system provided objective and quantitative measurements used to create a metric from the area under the curve (AUC) of the logarithmic normalized halo profile. This proposed metric differentiated between IOL models, and linear regression analysis found strong correlations between AUC and subjective clinical ratings of halos.

Conclusion

The HDR system produced quantitative, preclinical metrics that correlated to patients’ subjective perception of halos.

Clinical outcomes with distance-dominant multifocal and monofocal intraocular lenses in post-LASIK cataract surgery planned using an intraoperative aberrometer

IMPORTANCE

Studies evaluating the clinical benefits of intraoperative aberrometry (IA) in cataract surgery are limited.

BACKGROUND

The study was designed to determine whether IA improved clinical outcomes of post-laser in situ keratomileusis (LASIK) cataract surgery with different intraocular lenses (IOLs) implanted.

DESIGN

A retrospective chart review of clinical outcomes from one surgeon at one surgical centre was conducted. It included post-LASIK cataract surgeries where IA was used for the confirmation of IOL power, with either a distant-dominant multifocal IOL or a monofocal IOL implanted.

PARTICIPANTS

Records for 44 eyes of 31 patients were analysed.

METHODS

Differences in visual acuity (VA) and refractions by lens type were compared, and the effects of IA were evaluated.

MAIN OUTCOME MEASURES

Uncorrected distance VA and the percentage of eyes with a spherical equivalent refraction within 0.5D of the intended correction were the primary outcome measures.

RESULTS

There was no statistically significant difference in the percentage of eyes with uncorrected distance VA of 20/25 or better between IOL groups (P = 0.41). More eyes in the multifocal group had a refraction within 0.50D of intended (P = 0.03). In 39% of cases, the preoperative and IA power calculations suggested the same IOL power. When not equal, the IA results were not significantly more likely to be 'best' (P = 0.08).

CONCLUSIONS AND RELEVANCE

Results suggest that a history of previous LASIK is not a contraindication to use of distant-dominant multifocal IOLs. IA did not appear to improve clinical outcomes in post-LASIK eyes, although a positive trend was evident.

Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses

PURPOSE

To compare the visual acuity (VA) and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL) and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye.

PATIENTS AND METHODS

Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated.

RESULTS

Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P<0.05) at vergences from -0.5 to -1.5 D (from 2 m to 67 cm viewing distance, P<0.05). There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were "bothersome" (P<0.05).

CONCLUSION

Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at viewing distances from 60 to 40 cm, corresponding to computer or reading distance.

Outcomes of excimer laser enhancements in pseudophakic patients with multifocal intraocular lens

Purpose

The aim of this study was to assess visual and refractive outcomes of laser vision correction (LVC) to correct residual refraction after multifocal intraocular lens (IOL) implantation.

Patients and methods

In this retrospective study, 782 eyes that underwent LVC to correct unintended ametropia after multifocal IOL implantation were evaluated. Of all multifocal lenses implanted during primary procedure, 98.7% were refractive and 1.3% had a diffractive design. All eyes were treated with VISX STAR S4 IR excimer laser using a convectional ablation profile. Refractive outcomes, visual acuities, patient satisfaction, and quality of life were evaluated at the last available visit.

Results

The mean time between enhancement and last visit was 6.3±4.4 months. Manifest spherical equivalent changed from −0.02±0.83 D (−3.38 D to +2.25 D) pre-enhancement to 0.00±0.34 D (−1.38 D to +1.25 D) post-enhancement. At the last follow-up, the percentage of eyes within 0.50 D and 1.00 D of emmetropia was 90.4% and 99.5%, respectively. Of all eyes, 74.9% achieved monocular uncorrected distance visual acuity 20/20 or better. The mean corrected distance visual acuity remained the same before (−0.04±0.06 logMAR [logarithm of the minimum angle of resolution]) and after LVC procedure (−0.04±0.07 logMAR; P=0.70). There was a slight improvement in visual phenomena (starburst, halo, glare, ghosting/double vision) following the enhancement. No sight-threatening complications related to LVC occurred in this study.

Conclusion

LVC in pseudophakic patients with multifocal IOL was safe, effective, and predictable in a large cohort of patients.

Comparative visual performance with monofocal and multifocal intraocular lenses

Background

To compare near, intermediate, and distance vision, and quality of vision using appropriate subjective questionnaires, when monofocal or apodized diffractive multifocal intraocular lenses (IOLs) are binocularly implanted.

Methods

Patients with different binocular IOLs implanted were recruited after surgery and had their visual acuity tested, and quality of vision evaluated, at a single diagnostic visit between 3 and 8 months after second-eye surgery. Lenses tested included an aspheric monofocal and two apodized diffractive multifocal IOLs with slightly different design parameters. A total of 94 patients were evaluated.

Results

Subjects with the ReSTOR® +2.5 D IOL had better near and intermediate vision than those subjects with a monofocal IOL. Intermediate vision was similar to, and near vision slightly lower than, that of subjects with a ReSTOR® +3.0 D IOL implanted. The preferred reading distance was slightly farther out for the +2.5 D relative to the +3.0 D lens, and farthest for the monofocal. Visual acuity at the preferred reading distance was equal with the two multifocal IOLs and significantly worse with the monofocal IOL. Quality of vision measures were highest with the monofocal IOL and similar between the two multifocal IOLs.

Conclusion

The data indicate that the ReSTOR +2.5 D IOL provided good intermediate and functional near vision for patients who did not want to accept a higher potential for visual disturbances associated with the ReSTOR +3.0 D IOL, but wanted more near vision than a monofocal IOL generally provides. Quality of vision was not significantly different between the multifocal IOLs, but patient self-selection for each lens type may have been a factor.