Natural Intraocular Lens Research Articles

Comparison of glistenings formation and their effect on forward light scatter between the Acrysof SN60WF and Eternity Natural Uni NW-60 intraocular lenses

AimsTo compare the characteristics of glistenings and forward light scatter between the Alcon Acrysof SN60WF and Santen Eternity Natural Uni NW-60 intraocular lenses (IOLs).MethodsFive Acrysof SN60WF and five Eternity Natural...

Efficacy of vitrectomy for natural lens or intraocular lens dislocated into vitreous cavity combined with retinal detachment

Objective To investigate the results and complications of vitrectomy in the treatment of natural lens or intraocular lens dislocated into vitreous cavity combined with retinal detachment.Methods We retrospectively analyzed the clinical data of 26 eyes of 26 cases with natural lens or intraocular lens dislocated into vitreous cavity combined with retinal detachment who had undergone vitreoretinal surgery.Lens dislocation after blunt trauma was found in 7 eyes,and in other 19 eyes,natural lens or intraocular lens was dislocated during or after cataract surgery.The dislocated intraocular lens was removed through the limbal incision.The dislocated natural lens was removed by phacoemulsification in the vitreous cavity.The vitreous cavity was tamponaded with silicone oil in 14 eyes and C3F8 in other 12 eyes.16 eyes were treated with additional scleral buckling operation.The follow-up duration was 6-18 months,average (11.50 ±2.67) months.Results The dislocated natural lens and intraocular lens were all removed successfully in these 26 eyes.The total retinal reattachment was achieved in 23 eyes (88.46％),part reattachment was found in 2 eyes (7.69％),failure occurred in 1 eye (3.85％) due to severe proliferative vitreoretinopathy (PVR).The visual acuity was improved after operation in all eyes.Conclusion Vitrectomy for natural lens or intraocular lens dislocated into vitreous cavity combined with retinal detachment may achieve a high final retinal reattachment rate,but relatively bad functional results. Key words: Lens; Lens, intraocular; Dislocation; Detachment, retinal; Vitrectomy

Contrast Sensitivity and Spherical Aberration in Eyes Implanted with AcrySof IQ and AcrySof Natural Intraocular Lens: the Results of a Meta-Analysis

BackgroundTo systematically evaluate the visual performance of aspheric AcrySof IQ and spherical AcrySof Natural intraocular lens (IOL) after cataract surgery.Methodology/Principal FindingsPotential randomized controlled trials (RCTs) that involved implanting AcrySof IQ and AcrySof Natural were searched from PubMed, Web of science, EMBASE, Chinese Science and Technology Periodicals Databases and Cochrane Central Register of Controlled Trials. The methodological quality of the studies was assessed by the Jadad method. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) of best-corrected visual acuity (BCVA), contrast sensitivity and spherical aberration were pooled using a random-effects model. Seven studies were identified and analyzed to compare AcrySof IQ (236 eyes) with AcrySof Natural (232 eyes) after phacoemulsification. There was no significant difference in postoperative BCVA between AcrySof IQ and AcrySof Natural (p =0.137) after a follow up of 3 months. For contrast sensitivity, these differences reached statistical significance under photopic conditions at two spatial frequencies (3 cycles per degree (cpd), 6 cpd, 12 cpd, and 18 cpd; p =0.022, p =0.017, p = 0.065, and p=0.191, respectively) and under mesopic conditions at three spatial frequencies (3 cpd, 6 cpd, 12 cpd, and 18 cpd; p =0.007, p =0.033, p =0.030, and p =0.080, respectively). Eyes with AcrySof IQ also had statistically significant less spherical aberration than eyes with AcrySof Natural (p<0.001). Sensitivity analysis showed that the results were relatively stable and reliable.Conclusions/SignificanceThe overall findings indicate that AcrySof IQ with a modified aspheric surface induced significantly less spherical aberration than AcrySof Natural. Contrast sensitivity in eyes with AcrySof IQ is better than that in eyes with AcrySof Natural, especially under mesopic conditions.

Alpins and thibos vectorial astigmatism analyses: proposal of a linear regression model between methods

OBJETIVO: Estabelecer modelos de regressão linear entre os índices propostos por Alpins com os vetores astigmáticos de Thibos, avaliando a validade e a força dessas correlações. MÉTODOS: Série de casos na qual foram avaliados prospectivamente 62 olhos de 31 pacientes de catarata com astigmatismo corneano pré-operatório entre 0,75 e 2,50 dioptrias para ambos os olhos. Os pacientes foram aleatoriamente distribuídos entre 2 grupos: um submetido a implante de lente intraocular (LIO) AcrySof ToricTM em ambos os olhos e outro grupo, [...]

Visual performance of Acrysof ReSTOR compared with a monofocal intraocular lens following implantation in cataract surgery

The aim of this study was to compare the visual performance of Acrysof ReSTOR and Acrysof Natural intraocular lenses (IOLs) following cataract surgery. A randomized prospective study was performed in which 64 eyes (51 patients) were divided randomly into two groups. Monofocal IOLs (Acrysof Natural) were implanted into 34 eyes (27 patients) and multifocal IOLs (Acrysof ReSTOR) were implanted into 30 eyes (24 patients) using phacoemulsification surgery. The corrected distance visual acuity, near visual acuity, pseudoaccommodation, contrast sensitivity (CS) and wavefront analysis were measured at 1 week, 1 month and 3 months after surgery. The distance vision of the monofocal and ReSTOR patients improved equally with glasses (P<0.05). A greater improvement in near vision without glasses was observed in the ReSTOR-implanted patients (P<0.01). The CS values of the multifocal IOL group were significantly lower than those of the monofocal IOL group for all spatial frequencies tested (P<0.05). The spherical aberration was significantly higher in the multifocal IOL group compared with the monofocal IOL group (P<0.05). We observed no differences in coma between the two groups. The difference in the amplitude of pseudoaccommodation between the two groups was statistically significant (−3.14±0.91 D in the ReSTOR group vs. −1.03±0.33 D in the Natural group, P<0.01). The improvement in near vision was significantly more evident in the ReSTOR patients. Compared with the monofocal IOL lens, the multifocal lens is able to increase the amplitude of pseudoaccommodation. However, increased spherical aberration may contribute to lower CS values in the multifocal IOL group.

Accelerated 20-year sunlight exposure simulation of a photochromic foldable intraocular lens in a rabbit model

To assess the long-term biocompatibility and photochromic stability of a new photochromic hydrophobic acrylic intraocular lens (IOL) under extended ultraviolet (UV) light exposure. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. A Matrix Aurium photochromic IOL was implanted in right eyes and a Matrix Acrylic IOL without photochromic properties (n = 6) or a single-piece AcrySof Natural SN60AT IOL (n = 5) in left eyes of 11 New Zealand rabbits. The rabbits were exposed to a UV light source of 5 mW/cm(2) for 3 hours during every 8-hour period, equivalent to 9 hours a day, and followed for up to 12 months. The photochromic changes were evaluated during slitlamp examination by shining a penlight UV source in the right eye. After the rabbits were humanely killed and the eyes enucleated, study and control IOLs were explanted and evaluated in vitro on UV exposure and studied histopathologically. The photochromic IOL was as biocompatible as the control IOLs after 12 months under conditions simulating at least 20 years of UV exposure. In vitro evaluation confirmed the retained optical properties, with photochromic changes observed within 7 seconds of UV exposure. The rabbit eyes had clinical and histopathological changes expected in this model with a 12-month follow-up. The new photochromic IOL turned yellow only on exposure to UV light. The photochromic changes were reversible, reproducible, and stable over time. The IOL was biocompatible with up to 12 months of accelerated UV exposure simulation.

Reduced effect of glare disability on driving performance in patients with blue light–filtering intraocular lenses

To compare the effects of glare on driving performance in patients who had implantation of a blue light-filtering acrylic intraocular lens (IOL) and those who had implantation of an acrylic IOL with no blue-light filter. Department of Applied Psychology, Arizona State University, Mesa, Arizona, USA. Cross-sectional study. Patients with a blue light-filtering AcrySof Natural SN60AT IOL (study group) and patients with an AcrySof SA60AT IOL with no blue-light filter (control group) who had good visual acuity and a valid driver's license performed left-turn maneuvers in a driving simulator in front of oncoming traffic. The safety margin (time to collision minus time taken to turn at intersection with oncoming traffic) was calculated. The measurements were repeated with a glare source simulating low-angle sun conditions (daytime driving). With glare, the safety margin was statistically significantly greater in the study group (n= 17) than in the control group (n = 17) (mean 2.534 seconds ± 0.488 [SD] and 2.116 ± 0.511 seconds, respectively) (P < .05). Comparing no-glare conditions and glare conditions, the study group had significantly lower glare susceptibility, fewer collisions with the oncoming car, and a lower impact on intersection approach speed than the control group. The IOL incorporating blue light-filtering technology significantly reduced glare disability and improved the driver's ability to safely execute a left turn with oncoming traffic in the presence of glare simulating low-angle sun conditions. The real-world benefit of this technology is presumably mediated by a stronger signal to detect approaching objects (motion-in-depth) as a result of a reduction in glare disability. No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

Differences in Visual Performance of Acrysof ReSTOR IOL in High and Low Myopic Eyes

To determine the differences in refractive and visual results obtained in eyes with high and low myopia after multifocal intraocular lens (IOL) implantation. Monocular visual acuity for distance and near, with and without distance correction, and photopic and mesopic contrast sensitivity were measured at 6 months after surgery in 152 myopic eyes implanted with the AcrySof ReSTOR Natural (SN60D3) IOL. Two groups were created: high and low myopia (76 eyes in each). Monocular best distance-corrected visual acuity was 0.02+/-0.06 logMAR for low myopes and 0.05+/-0.09 logMAR for high myopes. Monocular best distance-corrected near visual acuity was 0.04+/-0.05 and 0.07+/-0.08 logMAR for low and high myopes, respectively. Contrast sensitivity for high myopic eyes under photopic conditions was lower, primarily at high spatial frequencies, in relation to low hyperopic. Differences between both groups were statistically significant for 6 and 18 cycles per degree (cpd) spatial frequencies (p<0.006). At mesopic level, high myopic eyes showed lower values compared to low myopic eyes for all spatial frequencies. However, these differences were only statistically significant for 3, 6, and 12 cpd (p<0.003). The AcrySof ReSTOR IOL provided good visual acuity and contrast sensitivity for both distance and near, with and without distance correction; however, better results were found in low myopic eyes compared to those obtained in eyes with high levels of myopia.

Outcomes and Patient Satisfaction After Presbyopic Bilateral Lens Exchange with the ResTOR IOL in Emmetropic Patients

To assess efficacy, safety, predictability, stability, and patient satisfaction after presbyopic lens exchange in emmetropic patients. A prospective, nonrandomized, masked, observational case series (self-controlled) of 46 emmetropic eyes of 23 consecutive patients (age range: 50 to 60 years) after presbyopic lens exchange with bilateral AcrySof ReSTOR Natural (SN60D3) intraocular lens (IOL) (Alcon Laboratories Inc) implantation were evaluated. Mean spherical equivalent refraction (SE) was -0.04±0.14 diopters (D) (range: +0.25 to -0.25 D). Monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected near visual acuity (UNVA), distance-corrected near visual acuity (DCNVA), and patient satisfaction were recorded preoperatively and 6 months after surgery. At 6 months postoperative, efficacy index at distance was 1.00. No eye lost ≥2 lines of CDVA, 5 eyes lost 1 line, 24 eyes did not change after surgery, 14 eyes gained 1 line, and 3 eyes gained 2 lines of visual acuity. Safety index at distance was 1.03. All eyes had a manifest SE within ±0.50 D of emmetropia. Mean postoperative SE was +0.14±0.22 D (range: -0.25 to +0.37 D). No eye lost >2 lines of DCNVA, 1 eye lost 2 lines, 3 eyes lost 1 line, 34 eyes did not change after surgery, and 8 eyes gained 1 line of visual acuity. Uncorrected near visual acuity was 0.95±0.07. Safety and efficacy indexes at near were 1.01 and 1.03, respectively. A patient satisfaction questionnaire showed that patients had a high level of satisfaction after presbyopic lens exchange surgery. Presbyopic lens exchange with implantation of the ReSTOR multifocal IOL in emmetropic eyes is an effective and safe procedure for presbyopia correction.

Ocular wavefront analysis and contrast sensitivity in eyes implanted with AcrySof IQ or AcrySof Natural intraocular lenses

This study aimed to compare ocular wavefront aberrations for pupil diameters of 4 mm and 6 mm, and contrast sensitivity, in eyes with AcrySof IQ and AcrySof Natural intraocular lenses (IOLs). Sixty eyes of 60 patients were enrolled in this prospective randomized study. After phacoemulsification the eyes received either AcrySof IQ SN60WF or AcrySof Natural SN60AT IOLs. One month after surgery, all patients underwent complete ophthalmological examination including corneal topography, wavefront analysis for pupil diameters of 4 mm and 6 mm, and contrast sensitivity measurements with the CSV 1000E instrument under photopic and mesopic conditions with and without glare. There was no statistically significant difference between groups in age, sex or other preoperative ocular characteristics (p > 0.05). Patients with AcrySof IQ IOLs had higher contrast sensitivity at 6 c.p.d. under photopic conditions, at 6 c.p.d. and 18 c.p.d. under mesopic conditions, and at 6 c.p.d., 12 c.p.d. and 18 c.p.d. under mesopic conditions with glare (p < 0.05). Corneal spherical aberration was 0.273 ± 0.074 μm in the AcrySof Natural group and 0.294 ± 0.086 μm in the AcrySof IQ group (p = 0489). Ocular spherical aberration was 0.362 ± 0.141 μm and 0.069 ± 0.043 μm (p < 0.001) for 6-mm diameter pupils and 0.143 ± 0.091 μm and 0.017 ± 0.016 μm (p < 0.001) for 4-mm diameter pupils, with AcrySof Natural and AcrySof IQ IOLs, respectively. There were no significant differences in other higher-order aberrations between the groups (p > 0.05). Aspherical AcrySof IQ IOLs significantly reduced spherical aberration for pupil diameters of both 4 mm and 6 mm and also improved contrast sensitivity more than spherical AcrySof Natural IOLs, especially in mesopic conditions.

Refractive and Visual Results after Implantation of the AcrySof ReSTOR IOL in High and Low Hyperopic Eyes

To assess the differences in refractive and visual results obtained in eyes with high and low hyperopia after implantation of a multifocal intraocular lens (IOL). A prospective study was performed on 172 hyperopic eyes implanted with the AcrySof Re-STOR Natural (SN60D3) IOL. Two groups were created, high and low hyperopes (86 eyes in both cases). We analyzed monocular visual acuity for distance and near, with and without distance correction. Photopic and mesopic contrast sensitivity (CS) were also assessed. All measurements were performed at 6 months after surgery. Monocular best distance-corrected visual acuity was 0.01+/-0.03 logMAR for low hyperopes and 0.04+/-0.10 logMAR for high hyperopes. Monocular best distance-corrected near visual acuity was 0.02+/-0.04 and 0.05+/-0.06 logMAR for low and high hyperopes, respectively. CS for high hyperopic eyes under photopic conditions was lower, primarily at high spatial frequencies, in relation to low hyperopic eyes. Differences between both groups were statistically significant for all spatial frequencies (p<0.004). At the mesopic level, high hyperopic eyes showed lower values compared to low hyperopic eyes for all spatial frequencies. However, these differences were only statistically significant for 1.5, 12, and 18 cpd (p<0.002). The visual acuity and CS for both distance and near, with and without distance correction, were statistically better in eyes with low hyperopia compared to those obtained in eyes with high levels of hyperopia.

Augmentation of Macular Pigment following Implantation of Blue Light–Filtering Intraocular Lenses at the Time of Cataract Surgery

(Photo)-oxidative stress is believed to play a role in the pathogenesis of age-related macular degeneration (AMD), with the threshold for retinal damage being lowest for short-wavelength (blue) light. Macular pigment (MP), consisting of the carotenoids lutein (L), zeaxanthin (Z) and meso-Z, has a maximum absorption at 460 nm and protects the retina from (photo)-oxidative injury. This study was designed to investigate whether the blue light-filtering properties of the Alcon AcrySof Natural intraocular lens (ANIOL) implanted during cataract surgery affects MP optical density (MPOD). Forty-two patients scheduled for cataract surgery were recruited for the study. These patients all had a preoperative best corrected visual acuity rating (BCVAR) of at least 0.5 (logMAR) in the study eye. The patients were randomized to have either the standard Alcon AcrySof three-piece acrylic intraocular lens (AIOL) (controls) or the ANIOL implanted at the time of cataract surgery. The spatial profile of MPOD (i.e., at 0.25 degrees, 0.5 degrees, 1.0 degrees, and 1.75 degrees eccentricity) was measured with customized heterochromatic flicker photometry (cHFP) 1 week before and 1 week after surgery, and at 3, 6, and 12 months after surgery. Serum concentrations of L and Z were also measured at each study visit. There was a highly significant and positive correlation between all MPODs (e.g., at 0.25 degrees) recorded 1 week before and after surgery in eyes with an AIOL implant (r = 0.915, P < 0.01; paired samples t-test, P = 0.631) and in those ANIOL implants (r = 0.868, P < 0.01; paired samples t-test, P = 0.719). Average MPOD across the retina increased significantly with time (after 3 months) in the ANIOL group (repeated-measures, general linear model, P < 0.05), but remained stable in the AIOL group (repeated-measures, general linear model, P > 0.05). There were no significant time or lens effects observed for serum L over the study period (P > 0.05). There was a significant time effect for serum Z over the study period (P < 0.05), but not a significant time/lens interaction (P > 0.05). Customized HFP can reliably measure the MPOD spatial profile in the presence of lens opacity, and cataract surgery does not artifactually alter MPOD readings. This study also provides evidence that implanting an IOL that filters blue light is associated with augmentation of MPOD in the absence of raised serum concentrations of L and Z. However, further and longitudinal study is needed to assess whether the observed increase in MPOD after implantation of blue-filtering IOLs is associated with reduced risk of AMD development and/or progression.

The Effect of the AcrySof Natural Lens on Glare Disability and Photostress

To investigate whether implanting "blue-filtering" yellow intraocular lenses (IOL) could provide a visual benefit in terms of glare disability and photostress recovery. A case-control study. Researchers masked to group assignments tested 58 subjects: 17 with yellow IOLs (AcrySof Natural; SN60WF; Alcon Laboratories Inc, Fort Worth, Texas, USA), 20 with clear IOLs, and 21 phakic controls. Photostress recovery and visual acuity under veiling glare conditions were assessed in a Maxwellian view optical system. Photostress recovery was assessed by measuring the time required to detect a grating stimulus (1 degree diameter) after a 5-second exposure to an intense circular disk (1 degree diameter) of broad-band xenon light. For the veiling glare experiment, subjects fixated on the grating stimulus, and the intensity of a broad-band xenon annulus (the glare source, 10 degrees inner, 12 degrees outer diameter) was adjusted until the grating stimulus was no longer seen. Subjects with AcrySof Natural (P < .0001) and clear IOLs (P < .035) could withstand significantly more light than the phakic controls. Subjects with the AcrySof Natural lens could withstand significantly more light (P < .02) than subjects with clear IOLs. Photostress recovery was significantly longer for subjects with clear IOLs vs phakic controls (P < .01), but the AcrySof Natural lens was not different from phakic controls (P < .09). Photostress recovery was similar between subjects with clear or AcrySof Natural lens (P < .32). The AcrySof Natural lens is related to reduced glare disability relative to a clear IOL or phakic controls.

New approach to evaluate retinal protection by intraocular lenses against age-related lipofuscin accumulation–mediated retinal phototoxicity

To present a new approach for evaluating intraocular lenses (IOLs) for retinal protection from age-related lipofuscin accumulation-mediated phototoxicity. Alcon Laboratories Inc., Fort Worth, Texas, USA, and Cardiff University, Cardiff, United Kingdom. Age-related lipofuscin accumulation-mediated action spectra for retinal phototoxicity in an aphakic eye were created for this evaluation. Transmission curves for 6 IOLs and for cornea and spectral radiant power distribution for sunlight and 2 lamps were used. Pseudophakic action spectra and retinal phototoxicity for 3 wavelength ranges and 3 ages were computed. The percentage protection of each IOL was computed as the reduction in phototoxicity relative to the aphakic eye. Retinal phototoxicity increased 3.66 times from the third to ninth decade of age. The comparative retinal phototoxicity and retinal protection provided by IOLs were dependent on the light source and range of wavelength; however, unlike phototoxicity, retinal protection was independent of age. The 420 to 480 nm range was the most useful for discriminating protection by IOLs. Retinal phototoxicity significantly increased with age; however, the retinal protection by IOLs was independent of age. The interaction between the transmission curve of IOLs and light sources required inclusion of widely used lamps besides sunlight for evaluation of IOLs. For the 420 to 480 nm wavelength range, the 3 light sources clearly discriminated the protection provided by IOLs. The AcrySof Natural IOL (Alcon) provided the highest protection consistently for the tested light sources.

Comparison of Higher Order Aberrations with Spherical and Aspheric Iols Compared to Normal Phakic Eyes

To compare higher order aberrations (HOA) in AcrySof SN60AT and Acrysof IQ SN60WF intraocular lenses (IOLs) and natural crystalline lenses in an age-matched population. Sixty-nine eyes of 55 patients were examined. Group I included AcrySof spheric lenses, group II AcrySof aspheric lenses, and group III included patients with the natural crystalline lens. The HOA data were obtained with a LADARWave aberrometer (Alcon Inc.). Analysis was based on the RMS of coma, spherical aberrations (SA), and HOA. Statistical comparisons were performed with Kruskal Wallis variance analysis. In the case of coma, there were statistically significant differences between spheric and aspheric AcrySof (p<0.005) and between spheric AcrySof and natural crystalline lenses (p<0.005). The differences between aspheric AcrySof and natural crystalline lens group were not significant (p>0.05). SA were significantly different between spheric and aspheric AcrySof group, and spheric AcrySof and natural crystalline lens group (p<0.005), as well as between aspheric AcrySof and natural crystalline lens group (p<0.05). In case of HOAno significant differences were observed between aspheric AcrySof and natural crystalline lens group (p>0.05), but differences between groups AcrySof spheric and aspheric, and spheric AcrySof and natural crystalline lens, showed high significance (p<0.005). The AcrySof Natural IQ aspheric model SN60WF IOL did not change the optical quality of vision compared to a healthy population of 60-80 years of age. The AcrySof Natural model SN60AT spherical IOL resulted in higher HOAs relative to both the natural crystalline lens population and eyes after aspheric AcrySof IQ model SN60WF IOL implantation.

Optical quality of the eye after lens replacement with a pseudoaccommodating intraocular lens

To examine the optical quality of healthy presbyopic eyes before and after implantation of the pseudoaccommodating AcrySof ReSTOR Natural intraocular lens (IOL) (Alcon Laboratories) by measuring visual acuity and wavefront aberrations. University of Valencia, Fernández-Vega Ophthalmological Institute, Valencia, Spain. Monocular refraction and photopic distance (6 m) and near (0.33 m) visual acuities were determined before and after clear lens extraction with bilateral AcrySof ReSTOR Natural IOL implantation in 30 hyperopic eyes (+0.50 to +4.00 diopters [D]) of presbyopic patients with low astigmatism (< or = 1.00 D). Postsurgical binocular visual acuity was measured over a range of effective distances. Wavefront aberrations were measured before and after surgery. Aberrations for 2 pupil diameters (3.0 mm and 5.0 mm) were decomposed using Zernike polynomials; total, defocus, astigmatism spherical, and coma aberration terms were studied separately. Postimplantation results were compared with preoperative values. Safety and efficacy indices for distance vision were 1.01 and 0.96, respectively. At near, they improved to 1.07 and 1.06, respectively. Vision at intermediate distances was noticeably poorer. Total, defocus, and spherical aberrations changed after IOL implantation with both pupil diameters (P<.01). Total and defocus aberrations were significantly reduced postoperatively. Spherical aberration coefficients changed to negative and less positive values for a 3.0 mm and a 5.0 mm pupil, respectively. Implantation of the pseudoaccommodating IOL in healthy eyes yielded uncorrected levels of high-contrast, distance, and near acuities comparable to preoperative best corrected values. Higher-order aberration levels appeared to be similar to the preoperative values.

Visual acuity tolerance to residual refractive errors in patients with an apodized diffractive intraocular lens

To assess visual acuity tolerance to defocus caused by residual refractive errors after clear lens extraction (CLE) with apodized diffractive intraocular lens (IOL) implantation. Fernández-Vega Ophthalmological Institute, Oviedo, Spain. In this prospective study, 150 eyes of 75 consecutive patients who had bilateral CLE with implantation of an AcrySof ReSTOR Natural IOL (Alcon) were evaluated. The eyes were divided into 2 groups: myopia and hyperopia. Residual refractive errors were analyzed using vector analysis. Monocular and binocular uncorrected distance visual acuity, best corrected distance visual acuity, uncorrected distance near visual acuity, and best distance-corrected near visual acuity 6 months after surgery were recorded. When the distance residual refractive error was corrected, there was a statistically significant improvement in uncorrected distance acuity in the myopia group and hyperopia group (P<.001). No differences were found between uncorrected-distance near acuity and best distance-corrected near acuity (P>.2). A significant trend toward worse visual acuity as a function of spherical equivalent (SE) value was significant only for uncorrected distance acuity (P<.001). No significant correlations were found for best corrected distance acuity, uncorrected-distance near acuity, and best distance-corrected near acuity as a function of SE (P>.2). Correction of distance residual refractive error improved distance visual acuity in patients with apodized diffractive IOLs. However, near visual acuity was maintained whether the residual refractive error was corrected or not.

Postoperative Optical Aberrations in Eyes Implanted With AcrySof Spherical and Aspheric Intraocular Lenses

To evaluate and compare optical and visual quality of eyes implanted with spherical and aspheric intraocular lenses (IOLs). Twenty eyes of 17 patients were implanted with the AcrySof Natural IQ aspheric IOL (SN60WF) and 20 eyes of 15 patients were implanted with the AcrySof Natural spherical IOL (SN60AT). Photopic monocular distance best spectacle-corrected visual acuity (BSCVA) was recorded at 6 months postoperatively. Corneal aberrations were measured with the CSO Eyetop topographer, and ocular aberrations were measured with a Hartmann-Shack aberrometer for a 6-mm pupil. Ocular spherical aberration was computed for different pupil diameters (3, 4, 5, and 6 mm). No statistically significant differences were found between the BSCVA of the AcrySof IQ IOL (0.023 +/- 0.004 logMAR) and AcrySof Natural IOL (0.031 +/- 0.003 logMAR) (P = .15). The corneal higher order aberrations showed no statistically significant differences between groups (P > .1). However, spherical aberration and higher order ocular aberrations in the AcrySof IQ eyes were lower than eyes implanted with the AcrySof Natural IOL (P < .01). A statistically significant increase in the spherical aberration coefficient with pupil diameter was found only for the spherical IOL group (P = .0023). Statistically significant differences in the spherical aberration coefficient were found between groups at all pupil diameters (P < .001). A significant reduction in ocular spherical aberration was noted after AcrySof IQ IOL implantation at all pupil diameters compared to the spherical IOL, although photopic BSCVA between groups remained similar.

Ocular aberrations and contrast sensitivity after cataract surgery with AcrySof IQ intraocular lens implantation: Clinical comparative study

To determine whether implantation of an intraocular lens (IOL) with a modified posterior aspherical surface (AcrySof IQ, Alcon Surgical Laboratories) results in reduced ocular aberrations (spherical aberration) and improved contrast sensitivity after cataract surgery. Brasilia Ophthalmologic Hospital, Brasilia, and Sao Geraldo Eye Hospital, Federal University of Minas Gerais, Belo Horizonte, Brazil. In an intraindividual randomized prospective study of 25 patients with bilateral cataract, an IOL with a modified posterior surface (AcrySof IQ) was compared with a biconvex IOL with spherical surfaces (AcrySof Natural, Alcon). Ocular aberrations with a 5.0 mm and 6.0 mm pupil were measured with a Hartmann-Shack aberrometer. Quality of vision was measured by visual acuity and contrast sensitivity under mesopic and photopic conditions. All patients were followed for 3 months. There were no statistically significant differences between eyes in postoperative uncorrected and best corrected distance visual acuities after a follow-up of 1 month and 3 months. Postoperatively, there was a statistically significant between-group difference in contrast sensitivity under photopic conditions without glare at 18 cycles per degree (cpd) (P = .04) and under mesopic conditions without glare at all spatial frequencies (3 cpd, 6 cpd, 12 cpd, and 18 cpd; P = .03, P = .009, P = .003, and P = .003, respectively) and with glare at 3 cpd and 6 cpd (P = .001 and P = .02, respectively). The difference in higher-order aberration (HOA) values between groups was statistically significant with a 5.0 mm and 6.0 mm pupil, with the AcrySof IQ IOL inducing less HOA than the AcrySof Natural IOL. Eyes with an AcrySof IQ IOL also had statistically significant less spherical aberration than eyes with an AcrySof Natural IOL with both pupil diameters (P<.001). The AcrySof IQ IOL with a modified posterior surface induced significantly less HOA and spherical aberration than the AcrySof Natural IOL. Contrast sensitivity was better under mesopic conditions with the AcrySof IQ IOL.

Aspheric intraocular lenses enhance contrast sensitivity

Evaluation of: Pandita D, Raj SM, Vasavada VA, Vasavada VA, Kazi NS, Vasavada AR. Contrast sensitivity and glare disability after implantation of AcrySof IQ natural aspherical intraocular lens: prospective randomized masked clinical trial. J. Cataract Refract. Surg. 33, 603–610 (2007).Intraocular lens (IOL) design is one of the major factors influencing visual function in pseudophakic eyes. Eyes implanted with a spherical IOL showed a reduction in the optical quality, caused, in part, by the increased positive spherical aberration of the IOL. Aspheric IOLs with negative spherical aberrations have been developed to compensate for the positive spherical aberrations of the cornea. Thus, aspheric IOLs have been used to increase the optical quality of pseudophakic eyes and, consequently, their visual quality. The paper under evaluation offers the results of a study assessing the contrast sensitivity and glare disability, as patient’s visual performance indexes, after implantation of an aspheric IOL. This study demonstrates that eyes implanted with the AcrySof® IQ aspheric IOL had significantly higher contrast sensitivity than those spherical IOLs under mesopic conditions, with and without glare.