Intraocular Lens Models Research Articles

In vitro comparative optical bench analysis of a spherical and aspheric optic design of the same IOL model

BackgroundTo analyse objective optical properties of the spherical and aspheric design of the same intraocular lens (IOL) model using optical bench analysis.MethodsThis study entailed a comparative analysis of 10 spherical C-flex 570 C and 10 aspheric C-flex 970 C IOLs (Rayner Intraocular Lenses Ltd., Hove, UK) of 26 diopters [D] using an optical bench (OptiSpheric, Trioptics, Germany). In all lenses, we evaluated the modulation transfer function (MTF) at 50 lp/mm and 100 lp/mm and the Strehl Ratio using a 3-mm (photopic) and 4.5-mm (mesopic) aperture.ResultsAt 50 lp/mm, the MTF values were 0.713/0.805 (C-flex 570 C/C-flex 970 C) for a 3-mm aperture and 0.294/0.591 for a 4.5-mm aperture. At 100 lp/mm, the MTF values were 0.524/0.634 for a 3-mm aperture and 0.198/0.344 for a 4.5-mm aperture. The Strehl Ratio was 0.806/0.925 and 0.237/0.479 for a 3-mm and 4.5-mm aperture respectively. A Mann–Whitney U test revealed all intergroup differences to be statistically significant (p < 0.01).ConclusionThe aspheric IOL design achieved higher MTF values than the spherical design of the same IOL for both apertures. Moreover, the differences between the two designs of the IOL were more prominent for larger apertures. This suggests that the evaluated IOL provides enhanced optical quality to patients with larger pupils or working under mesopic conditions.

Intraocular Lens Explantation After Cataract Surgery: Indications, Results, and Explantation Techniques.

Intraocular lens (IOL) explantation after uneventful cataract surgery is rare but associated with a high risk of complications. In the past few years, the number of published reports about IOL explantation has grown significantly and most of them focus on explantation surgery due to spontaneous late IOL in-the-bag dislocations. This is related to the growth of the pseudophakic population, first as a result of longer lifespans, and second, because the improvements in safety and accuracy of phacoemulsification surgery have led to an increased number of phacorefractive procedures performed in younger patients. The improvement in phacoemulsification surgery goes in tandem with higher patient demands and expectations of the surgery. Therefore, incorrect lens power or patients who fail to neuroadapt to multifocal IOLs are also well‑recognized indications for IOL explantation and exchange. IOL opacification, although it was an epidemic in the past especially associated with certain IOL models, is currently still occurring even with some new IOL models. The outcomes of explantation surgeries are analyzed in this review separately according to the reason for explantation. Finally, the main reported IOL explantation techniques are reviewed as well.

The comparative analysis of the effectiveness of implantation of toric, spherical and aspherical intraocular lenses for the surgical treatment of congenital cataract

Objective. The comparative analysis of the outcomes of the surgical treatment of the children presenting with congenital cataract and astigmatism following the implantation of toric, spherical, and aspherical intraocular lenses (IOLs). Materials and methods. A total of 97 children (127 eyes) presenting with congenital cataract were selected for the present study. Group 1 consisted of the patients suffering from corneal astigmatism of more than 1,0 D who had undergone toric IOLs implantation (25 children, 38 eyes). Group 2 was comprised of the patients with corneal astigmatism of more than 1,0 D who had undergone implantation of spherical and aspherical intraocular lenses (40 children, 48 eyes). Group 3 was composed of 32 children (41 eyes) with corneal astigmatism of less than 1,0 D who had undergone implantation of non-toric intraocular lenses. Lensectomy was performed with the use of the small (1,8 mm and 2,2 mm) incision technique. Various IOL models (Alcon, USA) were used for implantation. The vector analysis of astigmatic correction (Alpinus) was employed to evaluate the quality of astigmatism correction. Results. The patients of all groups experienced a significant improvement of postoperative non-correctable and maximally correctable visual acuity during the long-term follow-up period (over 3 years in duration). In the children comprising group 1, the estimated value of vector astigmatism (-0,72) was close to the actual postoperative value (-0,81). The TIA axis was 113,7 degrees and the SIA axis 92,6 degrees. The vector difference was 0,18 diopters which suggested the high precision of astigmatism correction. The correction index averaged 1,12 ± 0,14. The IOL index was 0,25 ± 0,16 in comparison with its ideal value of 0.0. In the children of group 2, the estimated value of vector astigmatism (-0,87) was significantly higher than the actual postoperative values (-0,56). The TIA axis was 134,3 degrees and the SIA axis 77,1 degrees (p

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

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. Four ophthalmic surgical sites, Japan. Prospective case series. One of 3 toric IOLs or 1 nontoric IOL was implanted in eyes having phacoemulsification and IOL implantation. 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 1day and 6.24±5.87 degrees at 1year. The results of other clinical parameters were excellent, with no significant differences between astigmatism categories or IOL models. 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. None of the authors has a financial or proprietary interest in any material or method mentioned.

Late postoperative opacification of a hydrophilic–hydrophobic acrylic intraocular lens

To report late postoperative opacification of a model of hydrophilic-hydrophobic acrylic intraocular lens (IOL) as well as the clinical consequences and laboratory characteristics. Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. Retrospective case series. Medical records were reviewed of patients with Lentis LS-502-1 IOL opacification reporting visual loss who had IOL explantation between November 2013 and March 2015. Patients were identified in the emergency room or during regular follow-up visits. Explanted IOLs were analyzed at the Ophthalmic Explants Biobank, Vissum, Spain, or at the John A. Moran Eye Center, University of Utah, USA. Twenty opacified IOLs were explanted from 19 patients. The mean interval between cataract surgery and diagnosis of opacification was 29.15months±9.57 (SD) (range 6 to 45months). Opacification led to a statistically significant reduction in corrected distance visual acuity (mean 0.86±0.76 logMAR; P<.001) and occurred in 5.1% of the hydrophilic-hydrophobic acrylic IOLs implanted at the department. The most frequently associated medical conditions were arterial hypertension, diabetes, and glaucoma. All IOLs but 1 had a similar pattern of opacification, with yellowish diffuse opacification uniformly distributed and calcium deposits on the surface and/or subsurface of the optic and haptics and within the IOL material. Opacification of the hydrophilic-hydrophobic acrylic IOL was found in a significant number of patients and had a significant effect on their vision. The opacification was attributed to primary calcification. None of the authors has a financial or proprietary interest in any material or method mentioned.

Special Intraocular Lenses in Refractive Lens Surgery

Many different models and types of special intraocular lenses (IOL) are now available for refractive lens surgery. In particular, toric and multifocal IOL need specific conditions to achieve satisfactory results. For multifocal IOL, many models with different optical principles are available. For optimal individual patient-centred care, it is necessary to consider several different options. With special refractive lenses, the principle objective for the patients is to become less dependent on glasses. Different IOL are evaluated on the basis of published studies and our own experience and data. IOL filtering blue light should not be classified as special IOL, but should be used as standards. Aspherical IOL are only beneficial in special situations. Toric IOL give reliable and good results, as long as certain specific requirements are considered. Multifocal IOL are still an optical compromise, although they are the only IOL that can reliably make the patient independent of glasses. To achieve satisfying results, the optimal IOL model should be selected individually. Many refractive needs can now be adequately satisfied by special IOL. The surgeon should provide ideal perioperative conditions, and he should be aware of the different IOL principles if he is to give the patient optimal advice. This can help to avoid upsetting both patients and ophthalmologists.

Topography, Wettability, and Electrostatic Charge Consist Major Surface Properties of Intraocular Lenses

ABSTRACTPurpose: To quantify potential relevant factors that affect the biocompatibility and functionality of intraocular lenses (IOLs) by analyzing the surface properties of various IOL materials.Methods: Eleven IOL models with the same dioptric power made by different manufacturers were studied. The IOLs were made of poly-methyl methacrylate (PMMA), hydrophobic acrylate, hydrophilic acrylate, and silicone. The IOL surface topography was evaluated using atomic force microscopy (AFM). Surface potential was measured by electric force microscopy (EFM). Surface wettability was assessed with the water contact angle using the sessile drop method.Results: The PMMA IOLs had statistically significant surface irregularities with the highest surface roughness values while the silicone and hydrophilic acrylic IOLs had the lowest values. Surface potentials on IOLs revealed that all IOL models made of PMMA had positive charge. The hydrophobic acrylic IOL had a significantly higher positive charge (6.2v ± 0.1v), while the hydrophobic acrylic with blue blocker exhibited negative charge. Negative charge was also observed on hydrophilic acrylic IOLs (–72mv ± 5mv) and silicone IOLs (–5.06v ± 0.02v). Contact angle values of PMMA IOLs ranged from 49° to 64°. Heparin modification resulted in significant reduction of the contact angle value. IOL models made of hydrophobic acrylate had contact angle values between 78° and 89°. The silicone IOL appeared to be significantly hydrophobic with the highest mean value of 107°.Conclusions: The variance of the parameters of surface roughness, contact angle, and electrostatic charge on the surfaces of PMMA, hydrophobic acrylic, hydrophilic acrylic, and silicone IOLs is useful to the interpretation of the differences in clinical behaviors of these materials. The negative surface charge of silicone and hydrophilic IOLs might account for the occurrence of IOL calcification.

Optimization of optical performance of biconvex Toric intraocular lens using a customized vision model

Background The optic quality of Toric intraocular lens (IOL)-implanted eye is affected by the residual astigmatism and individual difference of corneal spherical aberration and different magnification from steep and flat axis refraction.Whether correcting Toric IOL spherical aberration can effectively improve the image quality of individual patient is a question to be studied. Objective This study attempted to collect eye parameters of cataract patients to reconstruct the customized vision model by using Zemax optical software, and to evaluate the image performance with different Toric IOL spherical aberration. Methods A prospective study was performed.Forty-five eyes of 45 cataract patients were included in Second Hospital of Hebei Medical University from August 2012 to October 2013.Several relevant parameters were measured by Pentacam, including anterior and posterior surface height of cornea, corneal thickness, curvature radius of flat and steep meridians of anterior surface astigmatism, refractive diopter and curvature radius of posterior surface.The astigmatism of anterior and posterior corneal surface was described by Matlab 4.5 software.Corneal astigmatism model were set as aspheric state, and the effective position of Toric IOL was calculated using HolladayⅠformula.Customized individual model eyes were constructed by Zemax software.The contrast sensitivity function (CSF) of different spherical Toric IOLs at different spatial frequencies were calculated and compared between 300 Td light environment with 3 mm pupil diameter (photopia light) and 0.3-1.0 Td light environment with 5 mm pupil diameter (mesopia light). This study was approved by Second Hospital of Hebei Medical University ethics committee, all the patients signed the informed consent. Results The mean astigmatism power was (1.51±0.36)D and (1.49±0.37)D, and the mean astigmatism meridian was (101.5±59.8)° and (101.9±58.5)° in the model eyes and cataract eyes, respectively, without significant differences between them (t=0.886, 0.652; both at P>0.05). Bland-Altman test showed a good agreement in astigmatism power and astigmatism meridian between model eyes and cataract eyes.The LogCSF values at 1.5, 3.0, 6.0, 12.0 and 18.0 c/d spatial frequencies were significantly higher in the aspherical Toric IOL model eyes than those in the spherical Toric IOL model eyes, and the LogCSF values at various spatial frequencies were significantly higher in the Toric IOLs with spherical aberrations of -0.13 μm and -0.26 μm than those in the zero spherical aberrations in both photopia light and mesopia light (all at P<0.05). Conclusions A precise corneal astigmatism model based on cornea high data of cataract eyes was successfully constructed through special formulas with Zemax software.Aspherical Toric IOL can compensate for spherical aberration of cornea and enhance the optic quality in individual model eye. Key words: Lens, artificial; Astigmatism; Wavefront aberration; Corneal topography/methods; Imaging, three-dimensional/methods; Model; Algorithms; Computer simulation; Contrast sensitive function

Pupil Influence on the Visual Outcomes of a New-Generation Multifocal Toric Intraocular Lens With a Surface-Embedded Near Segment.

To evaluate the influences of preoperative pupil parameters on the visual outcomes of a new-generation multifocal toric intraocular lens (IOL) model with a surface-embedded near segment. In this prospective study, patients with cataract had phacoemulsification and implantation of Lentis Mplus toric LU-313 30TY IOLs (Oculentis GmbH, Berlin, Germany). The visual and optical outcomes were measured and compared preoperatively and postoperatively. The correlations between preoperative pupil parameters (diameter and decentration) and 3-month postoperative visual outcomes were evaluated using the Spearman's rank-order correlation coefficient (Rs) for the nonparametric data. A total of 27 eyes (16 patients) were enrolled into the current study. Statistically significant improvements in visual and refractive performances were found after the implantation of Lentis Mplus toric LU-313 30TY IOLs (P < .05). Statistically significant correlations were present between preoperative pupil diameters and postoperative visual acuities (Rs > 0; P < .05). Patients with a larger pupil always have better postoperative visual acuities. Meanwhile, there was no statistically significant correlation between pupil decentration and visual acuities (P > .05). Lentis Mplus toric LU-313 30TY IOLs provided excellent visual and optical performances during the 3-month follow-up. The preoperative pupil size is an important parameter when this toric multifocal IOL model is contemplated for surgery.

Three-dimensional ray-tracing model for the study of advanced refractive errors in keratoconus.

We propose a numerical three-dimensional (3D) ray-tracing model for the analysis of advanced corneal refractive errors. The 3D modeling was based on measured corneal elevation data by means of Scheimpflug photography. A mathematical description of the measured corneal surfaces from a keratoconus (KC) patient was used for the 3D ray tracing, based on Snell's law of refraction. A model of a commercial intraocular lens (IOL) was included in the analysis. By modifying the posterior IOL surface, it was shown that the imaging quality could be significantly improved. The RMS values were reduced by approximately 50% close to the retina, both for on- and off-axis geometries. The 3D ray-tracing model can constitute a basis for simulation of customized IOLs that are able to correct the advanced, irregular refractive errors in KC.

Ultra-widefield retinal imaging through a black intraocular lens

To evaluate the feasibility of ultra-widefield retinal imaging in patients with near infrared (IR)-transmitting black intraocular lenses (IOLs). Oxford Eye Hospital, Oxford, United Kingdom. Laboratory evaluation of a diagnostic technology with interventional case report. The field of retinal imaging through a Morcher poly(methyl methacrylate) (PMMA) black IOL was determined in a purpose-built adult schematic model eye with the HRA2 Spectralis confocal scanning laser ophthalmoscope using standard imaging, Staurenghi retina lens-assisted imaging, and ultra-widefield noncontact imaging. Retinal imaging using each modality was then performed on a patient implanted with another Morcher PMMA black IOL model. Ultra-widefield noncontact imaging and lens-assisted imaging captured up to 150 degrees of field (versus 40 degrees with a standard confocal scanning laser ophthalmoscope). Ultra-widefield retinal images were successfully acquired in a patient eye with a black IOL. This study has identified the first ultra-widefield retinal imaging modalities for patients with near IR-transmitting black IOLs. Should larger studies confirm this finding, noncontact ultra-widefield confocal scanning laser ophthalmoscopy might be considered the gold standard imaging technique for retinal surveillance in patients with near IR-transmitting black IOLs. No author has a financial or proprietary interest in any material or method mentioned.

Implantation of a diffractive trifocal intraocular lens: One-year follow-up

To evaluate the visual, refractive, contrast-sensitivity, and aberrometric outcomes during a 1-year follow-up after implantation of a trifocal intraocular lens (IOL). Premium Clinic, Teplice, Czech Republic. Prospective case series. This study included eyes of patients having cataract surgery with implantation of the trifocal IOL model AT Lisa tri 839MP. Distance, intermediate (66 and 80 cm), and near (33 and 40 cm) vision; contrast sensitivity; aberrometric outcomes; and the defocus curve were evaluated during a 12-month follow-up. The level of posterior capsule opacification (PCO) was also evaluated. In 120 eyes (60 patients), 1 month postoperatively, an improvement was observed in all visual parameters (P ≤ .03) except corrected near and intermediate visual acuities (both P ≥ .05). From 1 month to 12 months postoperatively, small but statistically significant changes were observed in uncorrected and corrected distance and near visual acuities (all P ≤ .03) and in uncorrected intermediate visual acuity (P = .01). In the defocus curve, no significant differences were found between visual acuities corresponding to defocus levels of -1.0 diopter (D) and -2.0 D (P = .22). The level of ocular spherical aberration decreased statistically significantly at 6 months (P < .001). Ocular and internal higher-order aberrations increased minimally but significantly from 6 to 12 months postoperatively (P < .001). The mean 12-month PCO score was 0.32 ± 0.44 (SD). Four eyes (3.3%) required neodymium:YAG capsulotomy. The trifocal IOL provided complete and stable visual restoration after cataract surgery during a 12-month follow-up, with good levels of visual quality. No author has a financial or proprietary interest in any material or method mentioned.

Long-term observation of surface light scattering in a foldable acrylic intraocular lens

To observe time-course changes in surface light scattering after Acrysof intraocular lens (IOL) implantation over 6 years postoperatively and its influence on visual function. Miyata Eye Hospital, Miyakonojo, Miyazaki, Japan. Retrospective comparative case series. Clinical records of eyes that had implantation of an Acrysof IOL (Group 1) or another IOL model (AR40 or Clariflex) (Group 2) were evaluated. Postoperative examinations including light scattering on the anterior surface of the IOL, corrected distance visual acuity (CDVA), and contrast sensitivity were performed 1 month and 3 years postoperatively. The same examinations were performed over the extended postoperative period, allowing analysis of time-course changes in surface light scattering and visual function. The study evaluated 24 eyes, 14 in Group 1 and 10 in Group 2. The mean time to the last postoperative examination was 8.4 years ± 1.0 (SD) (range 6.5 to 10 years). Surface light scattering in Group 1 increased, even after 3 years, at a rate of 12.02 computer-compatible tapes per year. Scattering did not increase in Group 2. The CDVA remained unchanged 3 to 6 or more years postoperatively in both groups. There was no difference in contrast sensitivity between the 2 groups 6 or more years postoperatively. Surface light scattering increased in Group 1, even after 3 years postoperatively; however, it did not affect visual function. No author has a financial or proprietary interest in any material or method mentioned.

Posterior chamber collagen copolymer phakic intraocular lens with a central hole to correct myopia: One-year follow-up

To assess the predictability, stability, efficacy, and safety of a newly developed posterior chamber phakic intraocular lens (pIOL) (model V4c Visian Implantable Collamer Lens) to correct moderate to high myopia. Fernández-Vega Ophthalmological Institute, Oviedo, Spain. Prospective case series. This study evaluated eyes that had implantation of the new pIOL model with a central hole for myopia correction. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density, pIOL vault, and adverse events were evaluated over 12 months. The study comprised 147 eyes of 80 patients. Preoperatively, the mean spherical equivalent (SE) was -8.80 diopters (D) ± 2.60 (SD). At 12 months, the mean SE was -0.14 ± 0.26 D, with 93.9% of eyes within ±0.50 D of the target and 100% of eyes within ±1.00 D. The mean UDVA and CDVA were 0.028 ± 0.055 logMAR and 0.003 ± 0.013 logMAR, respectively. The efficacy and safety indices were 1.00 and 1.04, respectively. All eyes had unchanged CDVA or gained 1 or more lines during the follow-up. The IOP remained stable over time; no eye developed anterior subcapsular cataract. Twelve months postoperatively, the mean vault was 405.5 ± 184.7 μm (range 100 to 980 μm), and the mean endothelial cell loss was 1.7%. The good refractive and visual acuity outcomes and the highly stable IOP values obtained over 12 months support the use of the new pIOL model with a central hole for the correction of moderate to high myopia. No author has a financial or proprietary interest in any material or method mentioned.

Intraindividual comparative analysis of capsule opacification after implantation of 2 single-piece hydrophobic acrylic intraocular lenses models: Three-year follow-up

To compare the 3-year postoperative anterior (ACO) and posterior (PCO) capsule opacification and the level of anterior capsule retraction after implantation of 2 single-piece hydrophobic acrylic intraocular lens (IOL) models. Hospital of St. John of God, Vienna, Austria. Comparative randomized controlled double-blind clinical trial. Eyes with bilateral cataract were evaluated. Each patient had an Acrysof SA60AT (interrupted optic edge) IOL implanted in 1 eye (Group A) and a Tecnis ZCB00 (continuous optic edge) IOL implanted in the fellow eye (Group B). One and 3 years postoperatively, PCO was evaluated using Evaluation of Posterior Capsule Opacification software and the ACO level and capsule-retraction level were evaluated and graded subjectively. The study evaluated 100 eyes of 50 patients ranging from 61 to 80 years. Postoperatively, there were no statistically significant differences in PCO between Group A and Group B at 1 year (0.06 ± 0.12 [SD] and 0.07 ± 0.13, respectively; P = 4.35) or 3 years (0.23 ± 0.36 and 0.22 ± 0.32, respectively; P = .66). In Group A and Group B, ACO was present in 18.0% of eyes and 2.7% of eyes, respectively, at 1 year (P = .03) and in 92.0% and 24.0%, respectively, at 3 years (P < .01). Capsule phimosis (18.0% at 1 year; 30.0% at 3 years) and glistenings (66.0% at 1 year; 86.0% at 3 years) were observed in Group A only. Both IOLs had similarly low PCO rates 3 years postoperatively, although more ACO and capsule retraction were observed in eyes with the interrupted optic edge IOL.

Influence of corneal asphericity on the refractive outcome of intraocular lens implantation in cataract surgery

To evaluate the possible influence of anterior corneal surface asphericity on the refractive outcomes in eyes having intraocular lens (IOL) implantation after cataract surgery. Fondazione G.B. Bietti IRCCS, Rome, Italy. Retrospective comparative case series. Intraocular lens power was calculated using the Haigis, Hoffer Q, Holladay 1, and SRK/T formulas. Asphericity (Q-value) was measured at 8.0 mm with a Placido-disk corneal topographer (Keratron), a rotating Scheimpflug camera (Pentacam), and a rotating Scheimpflug camera combined with Placido-disk corneal topography (Sirius). The relationship between the error in refraction prediction (ie, difference between expected refraction and refraction measured 1 month after surgery) and the Q-value was assessed by linear regression. The same IOL model (Acrysof SA60AT) was implanted in 115 eyes of 115 consecutive patients. Regression analysis showed a statistically significant relationship between the error in refraction prediction and the Q-value with all formulas and all devices. In all cases, a more negative Q-value (prolate cornea) was associated with a myopic outcome, whereas a more positive Q-value (oblate cornea) was associated with a hyperopic outcome. The highest coefficient of determination was detected between the Hoffer Q formula and the Placido-disk corneal topographer (R(2) = 0.2630), for which the error in refraction prediction (y) was related to the Q-value (x) according to the formula y = -0.2641 + 1.4589 × x. Corneal asphericity influences the refractive outcomes of IOL implantation and should be taken into consideration when using third-generation IOL power formulas. Dr. Hoffer receives book royalties from Slack, Inc., Thorofare, New Jersey, and formula royalties from all manufacturers using the Hoffer Q formula. No other author has a financial or proprietary interest in any material or method mentioned.

Visual outcomes after bilateral trifocal diffractive intraocular lens implantation.

BackgroundIn recent years new models of intraocular lenses are appearing on the market to reduce requirements for additional optical correction. The purpose of this study is to assess visual outcomes following bilateral cataract surgery and the implant of a FineVision® trifocal intraocular lens (IOL).MethodsProspective, nonrandomized, observational study. Vision was assessed in 44 eyes of 22 patients (mean age 68.4 ± 5.5 years) before and 3 months after surgery. Aberrations were determined using the Topcon KR-1 W wave-front analyzer. LogMAR visual acuity was measured at distance (corrected distance visual acuity, CDVA 4 m), intermediate (distance corrected intermediate visual acuity, DCIVA 60 cm) and near (distance corrected near visual acuity, DCNVA 40 cm). The Pelli-Robson letter chart and the CSV-1000 test were used to estimate contrast sensitivity (CS). Defocus curve testing was performed in photopic and mesopic conditions. Adverse photic phenomena were assessed using the Halo v1.0 program.ResultsMean aberration values for a mesopic pupil diameter were: total HOA RMS: 0.41 ± 0.30 μm, coma: 0.32 ± 0.22 μm and spherical aberration: 0.21 ± 0.20 μm. Binocular logMAR measurements were: CDVA −0.05 ± 0.05, DCIVA 0.15 ± 0.10, and DCNVA 0.06 ± 0.10. Mean Pelli-Robson CS was 1.40 ± 0.14 log units. Mean CSV100 CS for the 4 frequencies examined (A: 3 cycles/degree (cpd), B: 6 cpd, C: 12 cpd, D: 18 cpd) were 1.64 ± 0.14, 1.77 ± 0.18, 1.44 ± 0.24 and 0.98 ± 0.24 log units, respectively. Significant differences were observed in defocus curves for photopic and mesopic conditions (p < 0.0001). A mean disturbance index of 0.28 ± 0.22 was obtained.ConclusionsBilateral FineVision IOL implant achieved a full range of adequate vision, satisfactory contrast sensitivity, and a lack of significant adverse photic phenomena.Trial registrationEudract Clinical Trials Registry Number: 2014-003266-2.

Opacification of hydrophilic intraocular lenses after Descemet stripping automated endothelial keratoplasty.

PurposeOpacification of hydrophilic acrylic intraocular lenses (IOLs) is an emerging complication following Descemet stripping automated endothelial keratoplasty (DSAEK). We report six cases and review the current literature.MethodsIn this retrospective, noncomparative, observational case series, patients with IOL opacification after previous DSAEK surgery were identified from corneal clinic records. Case notes were reviewed for demographic details, indication for DSAEK, IOL model, incidence of rebubbling, and postoperative course.ResultsSix patients developed IOL opacification after DSAEK. All patients had Fuchs’ endothelial dystrophy and had previously received hydrophilic acrylic IOL models. Central anterior IOL opacification was noted in all six cases. Five cases (83%) had required rebubbling due to dislocated graft tissue, and one had an early postoperative intraocular pressure (IOP) rise. Five cases (83%) were managed conservatively, and one case with a failed graft underwent redo DSAEK and IOL exchange.ConclusionRepeated exposure to intracameral air, raised IOP, and other patient influences may be major etiological factors for IOL opacification after DSAEK. We advise avoiding hydrophilic acrylic IOL models in patients who may require future endothelial keratoplasty.

Comparison of visual outcomes of 2 diffractive trifocal intraocular lenses

To compare the visual outcomes after cataract surgery with bilateral implantation of 1 of 2 diffractive trifocal intraocular lenses (IOLs). Two clinical centers, Lisbon, Portugal. Prospective comparative case series. Phacoemulsification with bilateral implantation of a Finevision Micro F IOL (Group 1) or an AT Lisa tri 839 MP IOL (Group 2) was performed. Over a 3-month follow-up, the main outcome measures were uncorrected distance visual acuity (UDVA), corrected monocular and binocular distance visual acuity, uncorrected intermediate visual acuity at 80 cm, distance-corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity at 40 cm, distance-corrected near visual acuity (DCNVA), spherical equivalent (SE) refraction, defocus curves, contrast sensitivity, presence of dysphotopsia, and use of spectacles. Each group comprised 30 eyes (15 patients). The mean values at 3 months were UDVA, 0.03 logMAR ± 0.08 (SD) (Group 1) and 0.08 ± 0.12 (Group 2) (P = .765); DCIVA, 0.04 ± 0.07 logMAR and 0.18 ± 0.18 logMAR, respectively (P = .048); DCNVA, 0.03 ± 0.06 logMAR and 0.11 ± 0.08 logMAR, respectively (P = .032); SE, -0.25 ± 0.30 diopter (D) and -0.02 ± 0.39 D, respectively (P = .087). There was no significant difference in contrast sensitivity or dysphotopic phenomena between groups. Both trifocal IOL models provided excellent distance, intermediate, and near visual outcomes. Monocular DCIVA and DCNVA appeared slightly better in Group 1. Predictability of the refractive results and optical performance were excellent, and all patients achieved spectacle independence. Neither author has a financial or proprietary interest in any material or method mentioned.

Preoperative Evaluation of Cases with Aphakia and Intraocular Lens Dislocation by Ultrasound Biomicroscopy

The purpose of this study is to evaluate the capabilities of ultrasound biomicroscopy (UBM) as a diagnostic method for surgical planning of secondary intraocular lens (IOL) implantation in aphakia and intraocular lens dislocation. In this retrospective study, 19 eyes of 19 patients with aphakia and IOL dislocation that was not possible to evaluate by biomicroscopy because of the causes like corneal edema, opacity, anterior chamber reaction, ectopic pupil or poor pupil dilatation following cataract surgery were included. Ultrasound biomicroscopy was performed preoperatively to determine the capsule integrity, degree of ciliary sulcus support and iridocapsular adhesions. Seven patients with aphakia and 12 patients with posterior chamber IOL following cataract surgery were studied. Ultrasound biomicroscopy revealed that 4 of 7 eyes with aphakia had adequate capsule integrity (two eyes also had iridocapsular adhesions) and ciliary sulcus support, and 3 eyes had inadequate capsular remnant. Sulcus-supported posterior chamber IOLs were implanted in 4 eyes, and scleral-fixated posterior chamber IOLs were implanted in 3 eyes. Ultrasound biomicroscopy showed that 4 of 12 eyes with IOL dislocation had adequate capsule remnant, and there was no adequate capsular remnant and ciliary sulcus support in 8 eyes. IOL reposition or IOL exchange were performed in 4 eyes and IOL exchange and scleral-fixated posterior chamber IOLs implantation or scleral fixation of dislocated IOLs were performed in 8 eyes. In conclusion, ultrasound biomicroscopy helps the surgeon to select the appropriate surgical protocol by determining the capsule integrity, implant bed and iridocapsular adhesions preoperatively. It is also useful to choose the IOL model and its fixation type.