Impact of crossplay between ocular aberrations and depth of focus in topo-guided laser-assisted in situ keratomileusis outcomes

Purpose: To develop a nomogram in cases with mismatch between subjective and Topolyzer cylinder, and based on the magnitude of the mismatch, customize a treatment plan to attain good visual outcomes post?laser?assisted in situ keratomileusis (LASIK) surgery. Methods: The patients were evaluated preoperatively using corneal tomography with Pentacam. Five optimal corneal topography scans were obtained from the Topolyzer Vario were used for planning the LASIK treatment. For the nomogram purpose, the patients were divided into three categories based on the difference between the subjective cylinder and Topolyzer (corneal) cylinder. The first group (group 1) consisted of eyes of patients, where the difference was less than or equal to 0.4 D. The second group (group 2) consisted of eyes, where the difference was more than 0.4 D and the subjective cylinder was lesser than the Topolyzer cylinder. The third group (group 3) included eyes where the difference was more than 0.4 D but the subjective cylinder was greater than the Topolyzer cylinder. LASIK was performed with the WaveLight FS 200 femtosecond laser and WaveLight EX500 excimer laser. Assessment of astigmatism correction for the three groups was done using Aplins vector analysis. For comparison of proportions, Chi?square test was used. A P value less than 0.05 was considered statistically significant. Results: The UDVA was statistically significantly different when compared between groups 1 and 2 (P = 0.02). However, the corrected distance visual acuity (CDVA) was similar among all the three groups (P = 0.1). Group 3 showed an increase of residual cylinder by ?0.25 D, which was significant at intermediate and near reading distances (P < 0.05). Group 3 showed significantly higher target?induced astigmatism (TIA) compared to groups 1 and 2 (P = 0.01). The mean surgically induced astigmatism (SIA) was the least in group 2, which was statistically significant (P < 0.01). Conclusion: The outcomes for distance vision using our nomogram postoperatively were excellent, but further refinement for improving the near vision outcomes is required

Subjective visual quality, reading fluency and patient satisfaction with the extended depth of focus IOL / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the subjective visual quality, reading fluency and patient satisfaction after a unilateral or bilateral implantation of the Tecnis Symfony extended depth of focus intraocular lens(IOL)with cataract.<p>METHODS: The retrospective analysis on the 48 patients(71 eyes)with cataract phacomulsification surgery in our hospital, which were randomly divided into two groups. The bilateral group with 23 patients(46 eyes)bilateral implanted the Symfony extended depth of focus IOL, the unilateral group with 25 patients(25 eyes)implanted the Symfony IOL in one eye and an aspherical monofocal IOL in the other eye. The uncorrected distance visual acuity(UDVA), uncorrected intermediate distance visual acuity(UIVA), uncorrected near distance visual acuity(UNVA), and best corrected distance visual acuity(BCVA)were measured 3, 6mo after surgery. The contrast sensitivity, reading fluency, reading speed, patient satisfaction and the occurrence of complications were also observed.<p>RESULTS: In the unilateral group, there were no significant differences in the UDVA and BCVA between an eye with the Symfony IOL and an eye with monofocal IOL 3mo after surgery(P>0.05). After 6mo of surgery, UDVA were significantly better than pre-operation in two groups, average visual acuity of LogMAR was under 0.1. There were no significant differences in UDVA, BCVA, UIVA and UNVA between two groups(P>0.05). The patients'far, intermediate, and near distances satisfaction were higher after 3mo of surgery. There were no statistically significant differences in spatial frequency contrast sensitivity between the two groups under photopic/mesopic conditions and mesopic with glare 6mo after surgery. The scores of satisfactions for reading fluency were better in the bilateral group than in the unilateral group(P>0.05). After 6mo, the reading speed of binocular group was slightly higher than the unilateral group(P<0.05), but there was no significant difference between two groups(P >0.05).<p>CONCLUSION:The Symfony extended depth of focus IOL provides good far, intermediate, and near visual acuity in the bilateral group and the unilateral group, while maintaining the same level of visual quality. In both groups over 90% patients were spectacle independent. Symfony IOL has widely adaptability and highly predictability, patients can obtain better satisfactions for reading fluency and reading speed. It is more suitable for intermediate vision.

Comparison of visual quality between extended depth and trifocal intraocular lens implantation / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the visual quality between the Tecnis Symfony extended depth of focus intraocular lens(IOL)and Zeiss trifocal IOL(At Lisa tri 839 MP)implantation.<p>METHODS: Forty-two patients(53 eyes)who underwent cataract phacomulsification with IOL implantation from Jan. 2019 to Dec. 2020 were randomly divided into group A and group B according to the type of implanted IOL. The group A with 22 patients(29 eyes)implanted the Tecnis Symfony extended depth of focus IOL, the group B with 20 patients(24 eyes)implanted Zeiss trifocal IOL. The uncorrected distance visual acuity(UDVA), uncorrected intermediate distance visual acuity(UIVA), uncorrected near distance visual acuity(UNVA), and best corrected distance visual acuity(BCVA)were measured after 3mo of surgery. The defocus curve, the quality of life and the occurrence of complications were also observed.<p>RESULTS: The visual acuity was significantly improved in both groups after 3mo of surgery. There were no significant differences in the UDVA(5m), UIVA(80cm)and BCVA(5m)between the two groups(<i>P</i>>0.05). In group B, the UIVA(60cm)and UNVA(40cm)were better than in group A(all <i>P</i><0.05). The defocus curve analysis revealed that the group A tended to be stable between +1.0D to -2.0D, and to form a platform, while the group B had double peaks(0D, -2.5D). The distance visual acuity at 0D were no significantly differences between the two groups(<i>P</i>>0.05), but the near visual acuity at -2.5D and -3.5D in group B were significantly higher than in group A(all <i>P</i><0.01). In both groups over 90% patients were spectacle independent. Patients in the two groups showed different degrees of halo, glare and other optical phenomena, but the overall satisfaction were higher. The scores of satisfactions for reading speed and night vision were significantly better in group A than in group B(all <i>P</i><0.05). <p>CONCLUSION: In both groups over 90% patients were spectacle independent, they can obtain good near,intermediate and far distance visual acuity. Symfony extended depth IOL has better continuous intermediate distance visual acuity, patients can also obtain higher satisfaction and have better night vision. The Zeiss trifocal IOL implantation is associated with significantly better near visual acuity, and it is more suitable for near vision.

Measuring Defocus Curves of Monofocal, Multifocal and Extended Depth-of-focus Intraocular Lenses Using Optical Bench Test

PURPOSE: To determine the through-focus optical bench test performance of monofocal, bifocal, and extended depth-of-focus intraocular lenses (IOLs), and to measure their defocus curves.METHODS: A model eye was placed on an optical bench to test three different IOLs (TECNIS ZXR00, ZMB00, and ZCB00; Abbott Medical Optics, Santa Ana, CA, USA). The focus was changed by inserting trial lenses from +1.00 diopters to −4.00 diopters, in increments of +0.25 diopters. The 1951 United States Air Force Resolution chart was used to determine the quality of the images. The degree of similarity with reference images was given by the cross-correlation coefficient, and defocus curves were drawn and compared.RESULTS: Bifocal IOLs showed lower image quality with the addition of minus diopter trial lenses, but showed good image quality at near distance. Bifocal IOLs also showed a ‘double peak’ in their defocus curve. Monofocal IOLs showed a lower image quality and cross-correlation coefficient with addition of lower-diopter trial lenses. The extended depth of focus IOLs showed a single peak in their defocus curve, but had a wider range of diopters and better image quality than monofocal IOLs.CONCLUSIONS: Bifocal IOLs showed a double peak defocus curve, and extended depth of focus IOLs showed a wider diopter range and better image quality than monofocal IOLs.

Clinical Outcomes of Patients Implanted with Bifocal and Extended Depth of Focus Intraocular Lenses

PURPOSE: To compare the postoperative clinical outcomes after cataract surgery with implantation of bifocal intraocular lenses (IOLs) and extended depth of focus (EDOF) IOLs. METHODS: A total of 60 patients were divided into three groups, and each group included 20 patients of 40 eyes: group A with a +3.25 D bifocal IOL in both eyes, group B with an EDOF IOL in both eyes, and group C with a +3.25 D bifocal in one eye and an EDOF IOL in the other eye. We retrospectively reviewed the patients' medical charts to analyze their binocular uncorrected visual acuities (UCVAs; distant, intermediate, and near) and refraction at postoperative 3 months. RESULTS: The binocular distant UCVAs were 0.04 ± 0.01, 0.05 ± 0.02, and 0.04 ± 0.01 in groups A, B, and C, respectively, and there were no differences between the groups (p > 0.05). The intermediate UCVAs were 0.16 ± 0.01, 0.10 ± 0.01, and 0.10 ± 0.01, respectively, and group A was the lowest (A–B, p = 0.031; A–C, p = 0.018; B–C, p = 1.000). The near UCVAs were 0.05 ± 0.01, 0.24 ± 0.01, and 0.13 ± 0.01, respectively, and there were significant differences between the groups (A–B, p < 0.001, A–C: p = 0.009; B–C, p = 0.003). CONCLUSIONS: There were no significant differences among the three groups in binocular distant UCVA, and groups B and C showed better intermediate UCVAs than group A. Near UCVA was ranked in the order of groups A, C, B.

Extended focal length intraocular lens implantation in posttraumatic posterior capsular rupture

We present a case of posterior capsular defect with traumatic cataract after blunt trauma in which an extended focal length intraocular lens (IOL) was implanted in the bag after conventional phacoemulsification and anterior vitrectomy. Anterior segment optical coherence tomography performed preoperatively aided in the confirmation and documentation of the capsular integrity. Intraoperative trocar anterior chamber (AC) maintainer allowed AC maintenance without further complications. IOL was well centered postoperatively at 6 months, and the unaided visual acuity was 20/20 for distance and N8 for near. The report showed that an extended depth of focus IOL can be placed in eyes with ruptured posterior capsule for good visual outcome in posttraumatic young eyes and it may not be considered as a relative contraindication for it.

Visual outcomes of patients bilaterally implanted with the extended range of vision intraocular lens: A prospective study

Purpose: The aim of this study was to analyze the objective and subjective visual outcomes of patients bilaterally implanted with the extended range of vision intraocular lens (EROV IOL), the Tecnis Symfony. Methods: This was a prospective interventional case series conducted at a tertiary eye care hospital in South India. The study included patients with bilateral implantation of EROV IOLs. The uncorrected and corrected visual acuity for distance, intermediate, and near vision was recorded at 6 weeks and 6 months' postoperative visit. A subjective questionnaire was administered to assess spectacle independence, photic phenomenon, and overall satisfaction. All data were recorded using Microsoft Excel worksheet. The analyses were performed using SPSS for windows software. Results: Our study included fifty patients with bilateral implantation of EROV IOLs. The mean age was 59.84 ± 11.68 years. The mean uncorrected binocular distance, intermediate, and near visual acuity (in standard decimal equivalent) was 0.89,0.99 and 0.99 respectively, at 6 months' postoperative visit. Ninety-six percent of the patients did not require spectacles for distance and 98% of the patients were free from spectacles for intermediate and near vision. 94% of our patients perceived no or minimal photic phenomena such as glare and halos. The mean subjective patient satisfaction score (out of 10) for distance, intermediate, and near was 9, 10, and 9, respectively. Conclusion: The EROV IOLs demonstrated high levels of spectacle independence for distance, intermediate, and near vision. The incidence of photic phenomena observed was minimal with a high level of patient satisfaction.

A novel concept of accommodation:Human eyes optical system based on hyperfocal distance-micro zoom / 中华实验眼科杂志

Based on a concept of the hyperfocal distance from photographic lens,this study proposes that emmetropia presents far-hyperfocal distance,near-hyperfocal distance and accommodative hyperfocal distance.When emmetropic presbyopias completely lose the ability of accommodation,its farthest blur point is not beyond 1.5 m,even not being at infinity,and the phenomenon of dark focus both completely match with the definition of hyperfocal distance.On the other hand,after cycloplegic mydriatics in emmetropia,it could be found in the region of depth-of-field that there is no change in the back depth of field (clearness in far vision),but change was found in the front depth of field (blur in near vision).It conforms well to the definition of the hyperfocal distance,demonstrating that human eyes belong to the hyperfocal distance optical system.Furthermore,it is reported that the emmetropic presbyopias rarely matched the spectacles higher than +2.50 D in their whole life;therefore,it can be inferred that their accommodative amplitude in youth is equal to this corrected value.This value accounts for about 4％ of the total refractive power in human eyes,so it is suggested that human eye is a micro zoom optical system.Based on the objective existence of hyperfocal distance,the author proposes that human eye is an integrated accommodative mechanism.It includes three components:the accommodative mechanism of near vision,the measuring and controlling mechanism of near vision,and the general control of near vision.This paper discusses the accommodative mechanism of near vision and the resting mechanism of distance vision based on the hyperfocal distance,and considers that when human eye transfer into the accommodation of near vision from the normal distance vision of hyperfocal distance.There are three different pushing forces contributing to lens deformation and its anterior shift,and these forces cause four different accommodative efforts,which constitute the real accommodative efforts in the relative tissue.This paper also points out that it is only the mode of pushing accommodation that can make the lens vary refraction quickly and greatly,and control the amount of deformation effectively.That can not be achieved by the stretching mode proposed by Tscherning & Schachar,because some authors have verified that excessive pulling would result in decline in the refraction,which would be difficult to regulate and control the eye.Similarly,the self-bulging mode of Helmholtz & Gullstrand will not work neither,because it is unable to control the amount of lens deformation that is its fatal defect.

Comparative Study of Clinical Outcomes Between 2 Types of Multifocal Aspheric Intraocular Lenses

PURPOSE: To evaluate the efficacy of the OptiVis(TM) Multifocal intraocular lens (IOL) and compare the clinical outcome between OptiVis(TM) and AcrySof(R) ReSTOR(R) D1. METHODS: We reviewed 20 eyes of 11 patients implanted with OptiVis(TM) and 20 eyes of 10 patients implanted with AcrySof(R) ReSTOR(R) D1. The clinical outcomes of the 2 IOLs were evaluated 1 and 2 months postoperatively and consisted of distant, intermediate, and near visual acuity, depth of focus, contrast sensitivity, wavefront aberration, patient satisfaction, decentration and IOL tilt. RESULTS: Intermediate vision was better in the OptiVis(TM) group. There were no statistical differences between the 2 groups with respect to distant vision, near vision and wavefront aberration, contrast sensitivity, decentration and IOL tilt. Depth of focus was deeper in the OptiVis(TM) group at the intermediate visual acuity zone. There were no statistically significant result differences between postoperative 1 and 2 months. CONCLUSIONS: The OptiVis(TM) multifocal IOL provided satisfactory visual acuity at distance, near, and intermediate with no apparent reduction in contrast sensitivity. The IOL can be effective for improving patient satisfaction after cataract surgery as well as correcting presbyopia.

LASIK for Myopia with Presbyopia Using the Aspheric Micro-Monovision Technique

PURPOSE: To evaluate the efficacy, safety, and satisfaction of patients who underwent the aspheric micro-monovision protocol for the correction of myopia with presbyopia. METHODS: A retrospective, noncomparative study included 40 eyes of 20 consecutive patients with myopia and presbyopia who were treated with LASIK-induced micro-monovision. Monocular and binocular visual outcomes of uncorrected and best-corrected distance, intermediate, and near visual acuity were measured. Depth of focus, spherical aberration, stereopsis and satisfaction were evaluated before surgery and 3 months after surgery. RESULTS: Mean patient age was 48.7 years. Monocular uncorrected distance visual acuity was 0.8 in 94% of dominant eyes, and monocular uncorrected near visual acuity was J3 in 94% in non-dominant eyes. Binocular uncorrected near visual acuity was J2 in 94% and J5 in 100% of dominant and non-dominant patient eyes, respectively. Binocular uncorrected distance visual acuity was 1.0 in 100% of patients, and binocular uncorrected near visual acuity was J2 in 94% of patients. Our results showed a significant improvement in depth of focus and a positive shift in spherical aberration in dominant eyes; however, there were no significant changes in the non-dominant eyes. There was no change in stereopsis or contrast sensitivity at any of the tested spatial frequencies. Satisfactory scores were achieved in all eyes. CONCLUSIONS: The aspheric myopic micro-monovision protocol was well-tolerated, stable, and effective for treating patients with presbyopia in myopic astigmatism.

Comparison of Optical Performances in Eyes Implanted With Aspheric and Spherical Intraocular Lenses After Cataract Surgery

PURPOSE: To compare optical performances in eyes implanted with aspheric and spherical intraocular lenses (IOLs) after cataract surgery. METHODS: In 88 eyes of 69 patients, spherical (Sensar AR40; Acrysof natural SN60AT) or aspherical (Tecnis ZA9003; Acrysof IQ SN60WF) IOLs were implanted. After one month, contrast sensitivity, depth of focus, and spherical aberration were measured and compared between the groups. RESULTS: Contrast sensitivities of ZA9003 and SN60WF were significantly higher in 12,18 cycles per degree (CPD) under photopic conditions and were also higher in 6,12,18 CPD under mesopic conditions compared to those of respective spherical IOLs. Depths of focus were 1.31 D in ZA9003, 1.67 D in SN60WF, 1.52 D in AR40, and 1.49 in SN60AT, and the differences were not significant. Spherical aberration (Z40) with a 4 mm pupil was -0.032 microm in ZA9003, 0.022 microm in SN60WF, 0.076 microm in AR40, and 0.072 microm in SN60AT. Spherical aberration of SN60WF was significantly lower than spherical IOLs, and that of ZA9003 had the lowest among all IOL groups. Depth of focus significantly correlated with spherical aberration. CONCLUSIONS: Aspheric IOLs were superior in mesopic contrast sensitivity and equal in depth of focus to spherical IOLs. Individual corneal spherical aberration should be considered in the choice of IOLs.

Spherical Aberration, Contrast Sensitivity and Depth of Focus With Three Aspherical Intraocular Lenses

PURPOSE: To evaluate postoperative spherical aberration, contrast sensitivity and depth of focus after implanting 3 different aspheric intraocular lenses. METHODS: Fifty-six eyes (18 eyes for Akreos adapt Advanced Optics (AO), 20 eyes for AcrySof IQ SN60WF and 18 eyes for Tecnis Acrylic IOL ZA9003) of 48 patients were evaluated. Internal ocular aberration including spherical aberration and higher-order aberration and contrast sensitivity were evaluated 3 months after lens implantation. In addition, visual acuities at 33 cm and 1 m distance were measured with the far vision corrected state to calculate depth of focus. RESULTS: The total and internal ocular spherical aberration of the AO implanted group was slightly higher than the other groups with statistical significance. However, there was no statistically significant difference of contrast sensitivity and depth of focus among the 3 groups. CONCLUSIONS: A subtle difference of spherical aberration among the 3 groups without a statistically significant difference in other factors may not induce the differences of contrast sensitivities and depths of focus in each group.

Clinical Outcome of Diffractive Multifocal Aspheric Intraocular Lens

PURPOSE: To compare the clinical outcome between Tecnis ZM900 and Tecnis ZA9003. METHODS: We reviewed 20 eyes of 11 patients implanted with Tecnis ZM900 and 20 eyes of 20 patients implanted with Tecnis ZA9003. The clinical outcomes of these two intraocular lenses were evaluated one month after operation and consisted of distant, intermediate, and near visual acuity; depth of focus; contrast sensitivity; wavefront aberration; and patient satisfaction. Six months after the operation a reevaluation was performed for the group who had received the Tecnis ZM 900 implant. RESULTS: Near and intermediate vision was better in the Tecnis ZM900 group. There were no statistical differences between the two groups with respect to distant vision and wavefront aberration. Contrast sensitivity was better in the Tecnis ZA9003 group and depth of focus was deeper in the Tecnis ZM900 group. There were no statically significant differences in the result between one month and six month after the operation. CONCLUSIONS: The Tecnis multifocal ZM900 IOL can be effective at improving patient satisfaction after cataract surgery as well as for correcting presbyopia.

Long-Term Results of Presbyopic Corneal Surface Ablation with Eximer Laser

PURPOSE: To evaluate the efficacy, safety, and subjective symptoms of patients who underwent presbyopic corneal surface ablation. METHODS: Excimer laser surgery with MEL80 for refractive errors and presbyopia was performed on 128 eyes of 67 patients. Uncorrected and best-corrected visual acuity, distance-corrected near-visual acuity, spectacle near-addition for Jaeger 1, depth of focus, spherical aberration, and subjective symptoms were evaluated before surgery and 1 year after surgery. RESULTS: This study consisted of a myopia group (56 eyes), an emmetropia group (spherical equivalent or =20/40) was found in 96 eyes (75%) and spectacle near addition for Jaeger 1 decreased. Our results showed a significant increase of spherical aberration (from -0.19 micrometer to 0.11 micrometer) and depth of focus (from 1.45D to 1.69D). A significant positive correlation was found between spherical aberration and uncorrected far and near visual acuity and depth of focus. Loss of two lines of best corrected visual acuity occurred in 11 eyes (8.5%) at far vision and in 7 eyes (5.5%) at near vision. In general, patient satisfaction was good. CONCLUSIONS: Presbyopic corneal ablation with MEL80 showed good distant and near visual results and a wide depth of focus induced by increased spherical aberration.