The Effect of adding First Order Aberrations To Third Order Aberrations on Point Spread Function for Triangular Aperture

To measure and compare the optical quality of spherical and aspheric toric intraocular lenses (IOLs). Wavefront aberrations of AcrySof Toric and IQ Toric IOLs (Alcon Laboratories) for different powers were measured at 3- and 5-mm pupils by Nimo TR0805 instrument. The Zernike coefficients of trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration were evaluated. The point spread functions (PSFs) of each IOL evaluated were calculated from the wavefront aberrations. The PSF images also were calculated from the IOL wavefront aberrations, adding the cornea's aberrations to simulate the optical quality after their implantation. Spherical toric IOLs showed positive and aspheric toric IOLs negative spherical aberrations. Statistically significant differences were found in spherical aberration root mean square (RMS) values between spherical and aspheric IOLs for both pupil sizes (p<0.05). Aspheric toric IOLs showed higher spherical aberration RMS values. We found differences in PSF images between both IOL designs at 5-mm pupil. The PSFs corresponding to the aspheric toric IOLs showed more spread out than the PSFs corresponding to the spherical toric IOLs. However, when corneal aberrations were added, aspheric toric IOLs showed better optical quality than spherical toric IOLs. At 3-mm pupil, the optical quality between the IOL designs was similar, but at 5-mm pupil the optical quality was higher for spherical IOLs than aspheric IOLs. However, when theoretical corneal aberrations were added, aspheric toric IOLs showed better optical quality than spherical toric IOLs, due to the compensation between aspheric toric IOL negative spherical aberration and corneal positive spherical aberration.

To analyze the optical quality of aspheric toric intraocular lenses (IOLs) at different degrees of decentering. Wavefront aberrations of Acrysof IQ Toric IOLs (SN6AT3, SN6AT4, and SN6AT5; Alcon Laboratories Inc, Fort Worth, TX, USA) for different powers (15.00, 20.00 and 23.50 diopters [D]) and for different degrees of decentering (diagonal, horizontal, and vertical decentering of 0.3 and 0.6mm) were measured in vitro at 3- and 5-mm pupils. The Zernike coefficients of trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration were evaluated. The point spread functions (PSFs) and modulation transfer function (MTF) of each IOL evaluated were calculated from the wavefront aberrations. Coma aberration increased significantly with IOL decentration. Statistically significant differences were found between centered and all decentered positions in coma aberration (p < 0.05). Although, we only found visible differences between centered and decentered positions in PSF images and MTF curves for horizontal and vertical 0.6mm of decentering at 3- and 5-mm pupil. Despite the coma increment, these values were clinically negligible and have no effect on visual performance, except for vertical and horizontal 0.6mm of decentering, which could have a negative effect on visual quality.

To evaluate repeatability of the total high order aberrations with a retinoscopic wavefront sensor. This prospective case series analyzed 12 eyes from 6 patients who underwent wavefront measurement using retinoscopic aberrometry with the NIDEK Optical Path Difference Scan (OPD-Scan). Four consecutive wavefront measurements of each eye were taken by two trained examiners for 5.8+/-0.8-mm and 8.2+/-0.6-mm pupils (P=.002, Wilcoxon test). Total high order aberrations out to the eighth order were assessed including third order coma, third order trefoil, fourth order quadrafoil, fourth order secondary astigmatism, and fourth order spherical aberrations. Differences between measurements of all of the variables were analyzed. A P value <.05 was considered statistically significant. Repeatability analysis of the root-mean-square of total higher order aberrations, coma, trefoil, quadrafoil, secondary astigmatism, and spherical aberrations for both dilated and nondilated pupils did not show a statistically significant difference among all repeated measurements, except for trefoil and secondary astigmatism (analysis of variance and the Friedman test). The repeatability of total higher order aberrations was 0.15 microm for nondilated pupils and 0.18 microm for dilated pupils. Except for trefoil measurements, all high order aberrations showed reproducibility >0.15 microm when Zernike coefficients were analyzed individually. The NIDEK OPD-Scan aberrometer measures total higher order astigmatism and most individual aberrations with acceptable repeatability. However, measurement of trefoil with this instrument is less repeatable.

An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1,zoom ratio =1:4,and dual field are 26.6°and 5.6°respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320×240 pixels and 45μm pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First, the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner; Second, binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate; Others, in order to balance 5th spherical aberration, 5th coma aberration and 5th astigmatic aberration, high-order asphere surfaces with 2th order to 10thorder are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited, both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6°and the focal length is 152mm, MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6°and the focal length is 38mm, MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046,the coma aberration 0.055 and astigmatic aberration 0.034.

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.

PurposeTo compare the clinical outcomes of myopiacorrected with corneal-wavefront-guided (CWG) laser in situ keratomileusis (LASIK) with AMARIS 1050S (SCHWIND eye-tech-solutions GmbH & Co. KG) and corneal-topography-guided (CTG) LASIK with WaveLight EX500 (Alcon Laboratories, Fort Worth, TX).MethodsIn this prospective, pseudo-randomized expanded cohort study, a total of 266 patients were subjected to binocular LASIK surgery, either with WaveLight EX500 (WaveLight group) or Amaris 1050S (AMARIS group) platforms. Data related to right eyes were selected for analysis. Corneal higher-order aberration (HOA) was selected as the primary endpoint; while visual acuity and refraction were the secondary endpoints. All the endpoints were assessed at 3 months postoperatively.ResultsThere were 134 eyes in the AMARIS group and 132 eyes in the WaveLight group. After 3 months of postoperative follow-up, spherical and coma aberrations were significantly lower (P < 0.05) in the WaveLight group (spherical aberration: − 0.104 ± 0.199 µm; coma aberration: − 0.117 ± 0.202 µm) in comparison with the AMARIS group (spherical aberrations: 0.254 ± 0.146 µm; coma aberrations: 0.316 ± 0.297 µm). In the AMARIS group, 96.3% of the eyes achieved an uncorrected distance visual acuity (UDVA) of 20/20 while in the WaveLight group, 96.2% of the eyes achieved an UDVA of 20/20. Furthermore, the mean postoperative manifest refraction spherical equivalent (MRSE) was − 0.02 ± 0.28 in the AMARIS group and − 0.05 ± 0.21 in the WaveLight group (P = 0.34).ConclusionsBoth WaveLight EX500 and Amaris 1050S LASIK showed excellent refractive and visual outcomes. In addition, the WaveLight group showed minimal spherical and coma aberrations when compared to the AMARIS group.

Background: Rigid gas permeable (RGP) and silicone hydrogel (SH) contact lenses with specific designs are currently being used to improve visual function in patients with keratoconus. However, there are minimal data available comparing the effects of these lenses on visual function in patients with keratoconus. The objectives of this study were to compare visual acuity and contrast sensitivity using spectacles, RGP lenses, and SH lenses, and to evaluate the effects of RGP and SH lenses on higher-order aberrations and visual quality in eyes with keratoconus. The relationship between visual outcomes, aberration, and visual quality were also examined. Methods: This was a pilot study involving 13 eyes from nine subjects with keratoconus. Subjects were fitted with RGP and SH contact lenses. Visual acuity and contrast sensitivity were measured using Snellen and Pelli-Robson charts, respectively. Ocular aberrations and visual quality were measured using an OPD-Scan II device. All measurements were conducted before and after contact lens wear. Results: Significantly better visual acuity was obtained with RGP lenses than with spectacles or SH lenses ( P <0.001). No significant difference in contrast sensitivity values was detected between RGP and SH lenses ( P =0.06). Both SH and RGP lenses significantly reduced total ocular and higher-order aberrations ( P <0.001) when compared with spectacles, but RGP lenses reduced trefoil, coma, and spherical aberrations more than SH lenses. No significant difference in astigmatic aberrations was found between RGP and SH lenses ( P =0.12). Negative correlations were found between visual acuity and coma aberration and contrast sensitivity with higher-order aberrations and coma, trefoil, and astigmatic aberrations. Regarding visual quality, no significant difference was found between RGP and SH lenses, but RGP significantly improved visual quality when compared with spectacles ( P =0.04). Conclusion: RGP lenses provided better visual acuity and greater reduction of aberrations than spectacles or SH lenses in patients with keratoconus. However, more data are needed to confirm these findings. Keywords: visual acuity, contrast sensitivity, aberration, visual quality, keratoconus

Kligman, Brad E. MD; Baartman, Brandon J. MD; Dupps, William J. Jr MD, PhD Author Information

Objective To observe the efficacy of aberration elimination program in femtosecond assisted situ keratomileusis (FS-LASIK)for the correction of myopia and myopic astigmatism. Methods A prospective study. From Dec. 2013 to Aug. 2014, 76 eyes of 76 cases with myopia and myopic astigmatism received aberration elimination program FS-LASIK .The right eye was the object of study.There were 37 eyes of low to moderate myopia and myopic astigmatism(<-6.0D) and 39 eyes of high myopia and myopic astigmatism(≥-6.0D). The Optikon 2000 corneal wavefront aberration analyzer was used to examine the corneal higher-order aberrations before and 3 months after surgery. The corneal higher-order aberrations included spab, coma and total higher-order aberrations. Results The difference of spherical aberration, coma and total higher- order aberrations were not statistically significant between before and 3 months after surgery(t=1.999, 1.508, 1.435; P=0.053, 0.080, 0.075). The difference of corneal higher-order aberration of patients with low to moderate myopia and myopic astigmatism were not statistically significant between before and 3 months after surgery(t=1.530, 1.774, 2.053; P=0.120, 0.080, 0.052). The difference of the corneal higher-order aberrations of patients with high myopia and myopic astigmatism between before and 3 months after surgery were statistically significant (t=3.408, 5.372, 2.829; P=0.005, 0.000, 0.005). The variational ratio and multiple of higher -order aberrations in low to moderate myopia and myopic astigmatism were less than that in high myopia and myopic astigmatism. Conclusion The aberration elimination program can effectively reduce the higher- order aberrations especially in low to moderate myopic astigmatism after FS-LASIK. Key words: Aberration, higher-order; Femtosecond assisted laser in situ keratomileusis; Program aberration elimination

Purpose : To investigate the effects of age, refractive errors, corneal refractive power, pupil diameter, and pupil center shift on high-order aberrations (HOAs) in young myopic eyes. Methods : The myopic eyes of aged 20 to 39 years who had no ophthalmologic diseases and refractive surgery were recruited. I-Profilerplus (Zeiss, Berlin, Germany) was used to measure HOAs and refractive errors, corneal refractive power, pupil diameter, and pupil shift, and factors affecting HOA were analyzed. Results : In young myopes, as the age increased, the total HOA was increased in the positive (+) direction (p<0.001), and the horizontal coma, vertical coma, and spherical aberration (SA) were increased in the negative (-) direction (all, p<0.001). As the equivalent spherical refractive errors increased in the negative (-) direction, the total HOA was increased in the negative (-) direction (p<0.001), and the SA was increased in the positive (+) direction (p=0.004). As the mean corneal refractive power increased, the total HOA and SA were increased in the negative (-) direction (p<0.001, p=0.025), and the horizontal coma and vertical coma aberration were increased in the positive (+) direction (p=0.001, p<0.001). As the pupil diameter increased, vertical trefoil and SA were increased in the positive (+) direction (all, p<0.001). As the pupil center shift increased toward the lateral, the horizontal coma aberration increased in the positive (+) direction (p=0.003), and as the pupil center shift increased toward the superior, the vertical coma aberration increased positive (+) direction (p<0.001). Conclusion : The ocular HOAs of the young myopes changes according to age, refractive error, corneal refractive power, pupil size, and pupil center shift and the results in this study would be cornerstones in designing lenses for spectacle and contact lens.

We present estimated images of a hypothetical satellite system in the presence of Seidel aberrations. We exemplified the effects of defocus, spherical, coma, astigmatism, field curvature, and distortion aberrations. Our analysis methods allow the investigation of aberration effects individually and in any combined form. Thereby, we introduce a potentially rich analysis dimension for the imaging chain, image processing, and image quality analyses. For a number of degrees of aberrations, we provide image estimates, show and quantify how individual (field‐dependent) aberrations would introduce degradations on the satellite images. We got correlation coefficient values for defocus, spherical, coma, astigmatism, field curvature, and distortion aberrations as 0.69, 0.71, 0.66, 0.79, 0.76, and 0.60, respectively. Thereby, we identfied the significance order of Seidel aberrations for this system by using image simulations and image similarity measures.

Point spread function underneath spherical wave aberration with antiphase apodization has been obtained by one-dimensional pupil mask functions. In the presence of spherical aberration, suppression of optical side-lobes has increased on one side of the point spread function with the width of the periphery strips within the pupil mask. On introducing wave aberration effect, there exists dependence of the lateral resolution of central peak of the asymmetric point spread function on the amount of amplitude masking. However, the magnitude of intensity of central peak is originated be to amplified by the highest degree of amplitude and phase masking. Additionally, for aberrated asymmetric PSF, FWHM increases and it further decreases with the control parameters of amplitude and phase mask. The magnitude of this corollary can quantify the super resolution of diffracted structures under spherical aberration.

Objective To compare the higher order aberration of polychromatic light between blue light filtering intraocular lenses (IOLs) and transparent IOLs.Methods In an experimental study,blue light filtering IOLs (SN60AT,+20D) and transparent IOLs (SA60AT,+20D) were studied in the schematic eye.The images of the Hartmann-Shark for 3 different wavelengths were processed by a charge-coupled device (CCD) and analyzed in Matlab software.The Zernik polynomial,modulation transfer function (MTF) and point spread function (PSF) curve of the optical path were processed to evaluate the higher order aberrations of the polychromatic light with the two kinds of IOLs.Results The MTF curve of the SN60AT IOLs was low at all frequencies using a 486nm wave-light.The SN60AT IOLs had less higher order aberration,especially spherical aberration,for polychromatic light than the SA60AT IOLs as illustrated by PSF curves.Conclusion The blue light filtering IOL (SN60AT) had less higher order aberration of polychromatic light than the transparent IOL (SA60AT),especially in spherical aberration. Key words: Intraocular lenses; Aberration; Schematic eye; Blue light filtering

Effects of decentration and tilt on the optical performance of 6 aspheric intraocular lens designs in a model eye

This study measured the changes in visual acuity induced by individual Zernike ocular aberrations of various root-mean-square (RMS) magnitudes. A crx1 Adaptive Optics Visual Simulator (Imagine Eyes) was used to modify the wavefront aberrations in nine eyes. After measuring ocular aberrations, the device was programmed to compensate for the eye's wavefront error up to the 4th order and successively apply different individual Zernike aberrations using a 5-mm pupil. The generated aberrations included defocus, astigmatism, coma, trefoil, and spherical aberration at a level of 0.1, 0.3, and 0.9 microm. Monocular visual acuity was assessed using computer-generated Landolt-C optotypes. Correction of the patients' aberrations improved visual acuity by a mean of 1 line (-0.1 logMAR) compared to best sphero-cylinder correction. Aberrations of 0.1 microm RMS resulted in a limited decrease in visual acuity (mean +0.05 logMAR), whereas aberrations of 0.3 microm RMS induced significant visual acuity losses with a mean reduction of 1.5 lines (+0.15 logMAR). Larger aberrations of 0.9 microm RMS resulted in greater visual acuity losses that were more pronounced with spherical aberration (+0.64 logMAR) and defocus (+0.62 logMAR), whereas trefoil (+0.22 logMAR) was found to be better tolerated. The electromagnetic adaptive optics visual simulator effectively corrected and generated wavefront aberrations up to the 4th order. Custom wavefront correction significantly improved visual acuity compared to best-spectacle correction. Symmetric aberrations (eg, defocus and spherical aberration) were more detrimental to visual performance.