Simulations of Decentration and Tilt of a Supplementary Sulcus-Fixated Intraocular Lens in a Polypseudophakic Combination Using Ray-Tracing Software

This study aimed to assess image quality after the tilt and decentration of supplementary intraocular lenses (IOLs) in a two-lens configuration. One was designed for sulcus fixation with a nominal power range of 1D–10D and was combined with a capsular fixation 20D IOL. The optical performance of a ray-tracing model was tested under IOL misalignment through the area under the modulation transfer function (MTFa) and wave aberrations. Tilting by 10° resulted in a 4% reduction of the MTFa for a 10D IOL as compared to 9% for the 20D lens. The two models demonstrated good tolerance to a 1 mm decentration; as for the 10D sulcus-fixated lens, the MTFa loss was 2%, and 4% for the capsular fixation lens. Coma and astigmatism increased three- and four-fold, respectively, after a 10° tilt compared to the aberration level induced by the 1 mm decentration. Both analyses showed a trend towards a lower MTF impact and fewer optical errors with decreasing nominal power. In conclusion, when misaligned, low-power sulcus-fixated IOLs might retain their good optical quality. An extreme tilt of 10° has a more detrimental effect on the IOL performance than a 1 mm decentration. The proper alignment of a high-power capsular fixation lens is important in achieving a desirable postoperative outcome.

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Visual acuity and image quality in 5 diffractive intraocular lenses

European Journal of Ophthalmology ◽

10.5301/ejo.5000994 ◽

2017 ◽

Vol 28 (1) ◽

pp. 36-41 ◽

Cited By ~ 9

Author(s):

Genís Cardona ◽

Fidel Vega ◽

Miguel A. Gil ◽

Consuelo Varón ◽

José A. Buil ◽

...

Keyword(s):

Visual Acuity ◽

Image Quality ◽

Optical Quality ◽

Intraocular Lenses ◽

Modulation Transfer ◽

Multifocal Intraocular Lenses ◽

Corrected Distance Visual Acuity ◽

Good For

Purpose: To compare objective image quality at distant, intermediate, and near foci with the corresponding visual acuity (VA) in patients symmetrically implanted with 5 different diffractive multifocal intraocular lenses (IOLs) (ReSTOR SV25T0, Tecnis ZKB00, Tecnis ZLB00, AT LISA 809, and AT LISA Tri 839MP) and a monofocal lens (Tecnis ZA9003) 3 months after cataract intervention. Methods: Objective image quality, measured as the area under the modulation transfer function curve (AMTF), was tested in vitro in an eye model. In addition, corrected distance visual acuity and distance-corrected intermediate and near visual acuities (DCIVA and DCNVA) were assessed in a group of 79 patients, randomly implanted with one of the lenses. Results: Image quality and VA at the distant focus was good for all lens designs, but was similarly compromised at the intermediate focus, where the best DCIVA corresponded to the low add ZKB00. At the near focus, the monofocal lens and the distance dominant SV25T0 had the worst AMTF values, with the ZLB00 presenting the best DCNVA. The relationship between AMTF and VA was found not to be linear, with VA being similarly good for AMTF values over a certain threshold. Conclusions: Visual acuity of pseudophakic patients reflected the optical quality of the specific IOL design within a certain range of measurements, beyond which maximum VA is limited by other ocular, optical, and neuropsychophysical factors.

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Comparison of visual and optical quality of monofocal versus multifocal intraocular lenses

European Journal of Ophthalmology ◽

10.1177/1120672119827858 ◽

2019 ◽

Vol 30 (2) ◽

pp. 299-306 ◽

Cited By ~ 1

Author(s):

Irene Altemir-Gomez ◽

Maria S Millan ◽

Fidel Vega ◽

Francisco Bartol-Puyal ◽

Galadriel Gimenez-Calvo ◽

...

Keyword(s):

Visual Acuity ◽

Transfer Function ◽

Contrast Sensitivity ◽

Intraocular Lens ◽

Modulation Transfer Function ◽

Area Under The Curve ◽

Optical Quality ◽

Intraocular Lenses ◽

Modulation Transfer ◽

Multifocal Intraocular Lenses

Objective: To compare visual quality in patients implanted with Tecnis® monofocal (ZCB00) and multifocal (ZMB00) intraocular lenses taking into account their optical quality measured in vitro with an eye model. Methods: In total, 122 patients participated in this study: 44 implanted with monofocal and 78 with multifocal intraocular lenses. Measurements of visual acuity and contrast sensitivity were performed. The optical quality of the intraocular lenses was evaluated in three image planes (distance, intermediate and near) using an eye model on a test bench. The metric considered was the area under the curve of the modulation transfer function. Results: Optical quality at the far focus of the monofocal intraocular lens (area under the curve of the modulation transfer function = 66.97) was considerably better than that with the multifocal lens (area under the curve of the modulation transfer function = 32.54). However, no significant differences were observed between groups at the distance-corrected visual acuity. Distance-corrected near vision was better in the multifocal (0.15 ± 0.20 logMAR) than that in the monofocal group (0.43 ± 0.21 logMAR, p < 0.001), which correlated with the better optical quality at near reached by the multifocal intraocular lens (area under the curve of the modulation transfer function = 29.11) in comparison with the monofocal intraocular lens (area under the curve of the modulation transfer function = 5.0). In intermediate vision, visual acuity was 0.28 ± 0.16 logMAR (multifocal) and 0.36 ± 0.14 logMAR (monofocal) with p = 0.014, also in good agreement with the values measured in the optical quality (area under the curve of the modulation transfer function = 10.69 (multifocal) and 8.86 (monofocal)). The contrast sensitivity was similar in almost all frequencies. Pelli–Robson was slightly better in the monofocal (1.73) than in the multifocal group (1.64; p = 0.023). Conclusion: Patients implanted with multifocal ZMB00 achieved a distance visual acuity similar to those implanted with monofocal ZCB00, but showed significantly better intermediate and near visual acuity. A correlation was found between intraocular lenses’ optical quality and patients’ visual acuity. Contrast sensitivity was very similar between the multifocal and monofocal groups.

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Visual quality after implantation of trifocal intraocular lenses in highly myopic eyes with different axial lengths

International Journal of Ophthalmology ◽

10.18240/ijo.2021.03.06 ◽

2021 ◽

Vol 14 (3) ◽

pp. 371-377

Author(s):

Hui Liu ◽

◽

Hai-Jun Xia ◽

Jin Zhou ◽

◽

...

Keyword(s):

Visual Acuity ◽

Clinical Results ◽

Quality Parameters ◽

Optical Quality ◽

Intraocular Lenses ◽

Quality Analysis ◽

Modulation Transfer ◽

Distance Visual Acuity ◽

Refractive Outcomes ◽

Near Visual Acuity

AIM: To analyze postoperative clinical results after implantation of trifocal intraocular lenses (IOLs) in highly myopic eyes with different axial lengths (ALs). METHODS: This retrospective study describes 61 eyes of 44 patients that were implanted with trifocal diffractive IOLs (AT LISA tri 839MP). Twenty-one eyes (15 patients) were included in the AL<26 mm group, 19 eyes (13 patients) in the AL≥26 mm and <28 mm group, and 21 eyes (16 patients) in the AL≥28 mm group. Postoperative outcomes, including corrected and uncorrected distance visual acuity (UDVA), intermediate and near visual acuity at 167 cd/m2 luminance, depth of focus at 85 cd/m2 luminance, and objective optical quality parameters assessed using the Optical Quality Analysis System (OQAS), were compared among the groups at 3mo. RESULTS: There were no significant differences in the mean UDVA, uncorrected intermediate visual acuity, uncorrected near visual acuity, corrected distance visual acuity, distance-corrected intermediate visual acuity, and distance-corrected near visual acuity (DCNVA) among the three groups (P>0.05). Better near and intermediate visual acuity (from -1.5 D to -3.0 D) were noted on the defocus curve of the AL<26 mm group (P<0.01 vs AL≥28 mm group). Significantly higher objective scatter index (OSI) values and lower modulation transfer function (MTF) cut-off values, Strehl ratio (SR), and OQAS values (OVs) were observed in the AL≥28 mm group (P<0.01 vs AL<26 mm group). All OQAS parameters had statistically significant correlations with DCNVA and visual acuity at the vergence of -2.5 D (P<0.05 to P<0.01). CONCLUSION: Implantation of trifocal IOLs provides good short-term visual and refractive outcomes in highly myopic eyes with different ALs. However, the near vision decreases in the extremely myopic eyes at lower luminance, which is associated with the lower objective optical quality in these eyes.

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Misalignment and tilt effect on aspheric intraocular lens designs after a corneal refractive surgery

PLoS ONE ◽

10.1371/journal.pone.0243740 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0243740

Author(s):

Jesús Pérez-Gracia ◽

Francisco J. Ávila ◽

Jorge Ares ◽

Juan A. Vallés ◽

Laura Remón

Keyword(s):

Image Quality ◽

Refractive Surgery ◽

Spherical Aberration ◽

Optical Quality ◽

Intraocular Lenses ◽

Modulation Transfer ◽

Wavefront Aberrations ◽

Corneal Asphericity ◽

Corneal Refractive Surgery ◽

Image Position

Purpose To numerically evaluate and compare the tolerance to misalignment and tilt of aspheric intraocular lenses (IOLs) designed for three eyes: with standard cornea and with simulated corneas after myopic and hyperopic laser ablation surgery. Methods Three aspheric IOLs of +20.00 diopter (D) with different spherical aberration (SA) (Z40) values have been designed using a theoretical model eye. Drastic changes on the theoretical eye anterior corneal asphericity have been performed to simulate myopic and hyperopic refractive surgeries. The effect of IOL misalignment and tilt on the image quality has been evaluated using a commercial optical software design for the three eye models. Image quality was assessed from the modulation transfer function (MTF), root mean square (RMS) values of defocus, astigmatism, coma and spherical aberration (Z40), and retinal images obtained from a visual simulator using an aleatory optotype of 0.00 LogMar visual acuity (VA). Results IOL misalignment and tilt reduced MTF values in general, and increased wavefront aberrations errors. Aberration-free IOLs maintained best the MTF values when misalignments were applied, together with good on-axis optical quality. IOLs with negative SA (Z40) correction decreased the MTF value under 0.43 for misalignments values higher than 0.50 mm with the three corneas. The effect of misalignment on RMS astigmatism and coma was correlated with the IOL SA (Z40) and with the three corneas. Conclusions This theoretical study shows that the largest degradation in image quality arises for the IOL with the highest amount of spherical aberration (Z40). Moreover, it has been found that the aspherical design has a more influential role in misalignment tolerance than in tilt tolerance.

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

European Journal of Ophthalmology ◽

10.1177/1120672120926845 ◽

2020 ◽

pp. 112067212092684

Author(s):

Javier Ruiz-Alcocer ◽

Amalia Lorente-Velázquez ◽

Pablo de Gracia ◽

David Madrid-Costa

Keyword(s):

Transfer Function ◽

Intraocular Lens ◽

Modulation Transfer Function ◽

Optical Quality ◽

Significant Loss ◽

Intraocular Lenses ◽

Modulation Transfer ◽

The Impact ◽

Distance Vision

Background: The aim was to assess the impact of 5- and 10-degree rotations in the optical quality of a trifocal toric intraocular lens with different amounts of cylinder. Methods: Two Physiol Toric intraocular lenses with 1.5 and 3.0 D of cylinder were analysed in three different positions: centred, 5 and 10 degrees rotated. The optical quality of the intraocular lenses was evaluated with the PMTF optical bench through specific perpendicular targets. The analysis was performed by the through-focus modulation transfer function curves and the modulation transfer function corresponding to distance vision (0 D of vergence). Results: For a centred situation, the through-focus modulation transfer function curves of both intraocular lenses showed the classical three peaks corresponding to the powers of the two principal meridians of the intraocular lenses. When 5 and 10 degrees of rotation were induced, the three peaks were attenuated in both cases. The case with the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation showed the worst optical quality and a significant loss of trifocality. The modulation transfer function values obtained for distance vision also showed the worst optical quality for the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation. Conclusion: Rotations over 5 degrees decreased the optical quality of trifocal toric intraocular lenses, being this reduction moderate from 5 to 10 degrees for low levels of cylinder (≤1.5 D). For mid-high levels of cylinder (≥3.0 D), rotations over 5 degrees cause a significant loss of optical quality at all object distances.

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Optical Bench Analysis of 2 Depth of Focus Intraocular Lenses

Biomedicine Hub ◽

10.1159/000519139 ◽

2021 ◽

pp. 77-85

Author(s):

Andreas F. Borkenstein ◽

Eva-Maria Borkenstein ◽

Holger Luedtke ◽

Ruediger Schmid

Keyword(s):

Spherical Aberration ◽

Optical Design ◽

Individual Case ◽

Optical Quality ◽

Intraocular Lenses ◽

Optical Bench ◽

Modulation Transfer ◽

Depth Of Focus ◽

The Individual ◽

The Right

Background: The aim of the study was to analyze the objective optical properties of 2 enhanced depth of focus (EDoF) intraocular lenses (IOLs) using optical bench analysis. Methods: This experimental study investigates 2 new EDoF IOLs, the Alcon AcrySof IQ Vivity and the Bausch & Lomb LuxSmart Crystal, on the optical bench, using OptiSpheric IOL PRO2 (Trioptics, Germany) in order to assess the optical quality according to ISO 11979 with ISO-2 Cornea. IOLs (power 22.0 D) were evaluated regarding modulation transfer function (MTF) at 50 lp/mm and Strehl ratio (SR) using a 3.0-mm and a 4.5-mm aperture. In addition, wavefront measurements were obtained using WaveMaster® IOL 2 device (Trioptics, Germany), and USAF targets were analyzed. Results: Centered: the MTF (mean) at 50 lp/mm (AcrySof IQ Vivity/LuxSmart Crystal) with 3.0 mm aperture was 0.250/0.257 and with 4.5 mm aperture 0.202/0.243. The SR (mean) with 3.0 mm aperture was 0.261/0.355 and with 4.5 mm aperture 0.176/0.206. Decentered by 1 mm: the MTF (mean) at 50 lp/mm (AcrySof IQ Vivity/LuxSmart Crystal) with 3.0 mm aperture was 0.266/0.247 and with 4.5 mm aperture 0.126/0.215. The SR (mean) with 3.0 mm aperture was 0.272/0.234 and with 4.5 mm aperture 0.133/0.183. Tilted by 5 degree: the MTF (mean) at 50 lp/mm (AcrySof IQ Vivity/LuxSmart Crystal) with 3.0 mm aperture was 0.221/0.360 and with 4.5 mm aperture 0.214/0.229. The SR (mean) with 3.0 mm aperture was 0.232/0.428 and with 4.5 mm aperture 0.225/0.229. The simulated visual function using USAF test targets showed corresponding qualitative results. Wavefront measurements proved a complex optical design. Higher order aberrations in the central part of the optics were modulated up to the 10th order to enhance the range of functional vision to near distance, leaving the peripheral parts of the optics aberration free or as aberration correcting. Conclusion: The diversity of EDOF IOLs, their optics, and their respective impact on the vision quality must be understood in order to select the appropriate IOL in each individual case. This analysis of new, innovative IOL optics based on increased negative spherical aberration may help the ophthalmic surgeon to select the IOL which meets the individual requirements of the patient for best postoperative outcomes. It seems that there is no perfect IOL that is equally suitable for all patients, but the right choice is an individual, customized approach dealing with patients’ expectations.

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Correlation between polychromatic image quality metrics to predict visual acuity in pseudophakic patients

EPJ Web of Conferences ◽

10.1051/epjconf/202023812005 ◽

2020 ◽

Vol 238 ◽

pp. 12005

Author(s):

Jesús Armengol ◽

Nuria Garzón ◽

Fidel Vega ◽

Irene Altemir ◽

María S. Millán

Keyword(s):

Visual Acuity ◽

Modulation Transfer Function ◽

Optical Quality ◽

Intraocular Lenses ◽

Modulation Transfer ◽

Multifocal Intraocular Lenses ◽

Mathematical Expressions ◽

High Linear Correlation

The optical quality of three multifocal intraocular lenses (MIOLs) was measured in vitro using the area under the modulation transfer function (MTFa) and energy efficiency (EE). We evaluated those metrics through-focus (TF) by axially scanning the image space with three wavelengths (R, G, B). High linear correlation between MTFa and EE was found for all cases. Correlations between optical in vitro results (polychromatic TF-MTFa and TF-EE) and clinical visual acuity (VA) defocus curves for the three MIOLs allowed us to derive mathematical expressions. Both metrics proved to be equivalent to predict postoperative VA.

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INTERCOMPARATIVE STUDY OF LONG-YEAR WAVE HINDCASTING DATA SAMPLES BY USE OF BACKWARD RAY TRACING MODEL AND SWAN MODEL UNDER MSM-BASED WINDS CONDITION PROVIDED BY JMA

Journal of Japan Society of Civil Engineers Ser B1 (Hydraulic Engineering) ◽

10.2208/jscejhe.74.i_457 ◽

2018 ◽

Vol 74 (4) ◽

pp. I_457-I_462

Author(s):

Masataka YAMAGUCHI ◽

Hirokazu NONAKA ◽

Yoshio HATADA ◽

Yoshihiro UTSUNOMIYA ◽

Kunimitsu INOUCHI ◽

...

Keyword(s):

Ray Tracing ◽

Swan Model ◽

Wave Hindcasting ◽

Ray Tracing Model

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Comparison of the visual performance of iris-fixated phakic lens and implantable collamer lens to correct high myopia

BMC Ophthalmology ◽

10.1186/s12886-021-01995-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xiao-ling Jiao ◽

Jun Li ◽

Zhe Yu ◽

Ping-hui Wei ◽

Hui Song

Keyword(s):

Visual Acuity ◽

High Myopia ◽

Optical Quality ◽

Visual Performance ◽

Quality Analysis ◽

Modulation Transfer ◽

Implantable Collamer Lens ◽

Good Visual Acuity ◽

Significant Difference ◽

Group 6

Abstract Background To compare visual performance between the iris-fixated phakic intraocular len (pIOL) and implantable collamer len (ICL) to correct high myopia. Methods Twenty-four eyes underwent iris-fixated pIOL implantation and 24 eyes underwent ICL implantation. At the 6-month follow-up, the best-corrected visual acuity (BCVA) and uncorrected distance visual acuity (UDVA) were compared between the iris-fixated pIOL and ICL groups. The objective scatter index (OSI), modulation transfer function (MTF) cutoff, and ocular aberrations were performed to evaluate postoperative visual quality between the two groups. Results No significant difference was found in UDVA, BCVA, and spherical equivalent between the iris-fixated pIOL and ICL groups (P > 0.05). Six months after surgery, the following values were significantly higher in the ICL group than in the iris-fixated pIOL group: MTF cutoff, strehl ratio and optical quality analysis system values at contrasts of 9 %, 20 %, and 100 % (P < 0.01). The OSI in the iris-fixated pIOL group was higher than in the ICL group 6 months after surgery (P < 0.01). All high-order aberrations were slightly more severe in the iris-fixated pIOL group than in the ICL group 6 months after surgery, although only trefoil (P = 0.023) differed significantly in this regard. Conclusions Both iris-fixated lenses and ICLs can provide good visual acuity. ICLs confer better visual performance in MTF-associated parameters and induce less intraocular light scattering than iris-fixated pIOLs.

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

European Journal of Ophthalmology ◽

10.1177/11206721211002121 ◽

2021 ◽

pp. 112067212110021

Author(s):

Javier Ruiz-Alcocer ◽

Irene Martínez-Alberquilla ◽

Amalia Lorente-Velázquez ◽

José F Alfonso ◽

David Madrid-Costa

Keyword(s):

Visual Quality ◽

Optical Quality ◽

Refractive Errors ◽

Focal Points ◽

Modulation Transfer ◽

Optical Analysis ◽

Toric Intraocular Lens ◽

Toric Iols ◽

Reference Situation

Purpose: To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced. Methods: This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D). Results: The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively. Conclusion: For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

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