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Objective:To evaluate the optical performance of two aspheric intraocular lenses (IOL) AcrySof IQ SN60WF and Proming A1-UV with identical negative spherical aberration values, using the optical bench OptiSpheric IOL R&D through an in vitro study. Methods:The optical performance of + 20.0 D blue-light filtering SN60WF and monofocal high-order aspheric non blue-light filtering A1-UV IOL was evaluated through cornea models with the spherical aberration of 0 μm (ISO-1) and + 0.28 μm (ISO-2) under apertures of 3.0 mm and 4.5 mm via the optical bench OptiSpheric IOL R&D.The modulation transfer function (MTF) and USAF 1951 resolution test chart were employed to measure the IOL with centering, decentration of 0.3, 0.5, 0.7, 0.9 and 1.1 mm, as well as tilt of 3°, 5°, 7°, 9° and 11°.The spectral transmittance of IOL was measured with the UV-3300 UV-VIS spectrophotometer.Results:Compared with the A1-UV IOL, the spectral transmittance of SN60WF for blue light with wavelengths of 400-500 nm was significantly reduced, which effectively reduced the passage of blue light.At an aperture of 3.0 mm, the MTF values at 100 lp/mm spatial frequency for the centered SN60WF and A1-UV were 0.576 and 0.598 under ISO-1 corneal measurement conditions, 0.564 and 0.563 under ISO-2 conditions.At an aperture of 4.5 mm, the MTF values were 0.238 and 0.404 under ISO-1 corneal measurement conditions, and 0.438 and 0.339 under ISO-2 conditions.The MTF values of A1-UV and SN60WF at 3.0 mm aperture and 100 lp/mm spatial frequency under ISO-1 corneal measurement conditions were larger than those under ISO-2 corneal measurement conditions.Under ISO-1 corneal measurement conditions with a 3.0 mm aperture, A1-UV had a better optical quality compared to SN60WF, whereas under ISO-2 corneal measurement conditions, the optical quality of both IOLs was similar.Under the 3.0 mm aperture, the MTF values of SN60WF and A1-UV at a decentration of 0.3 mm and 100 lp/mm spatial frequency were 0.414 and 0.571 under ISO-1 corneal measurement conditions, 0.438 and 0.512 under ISO-2 corneal measurement conditions, respectively.The MTF values of SN60WF and A1-UV at a tilt of 3° were 0.522 and 0.597 under ISO-1 corneal measurement conditions, and 0.532 and 0.531 under ISO-2 corneal measurement conditions.The MTF values and USAF resolution test chart of A1-UV had no significant change between the two corneal measurement conditions.When subjected to equal degrees of decentration or tilting, except for the ISO-1 corneal measurement conditions at a 4.5 mm aperture, the MTF values of A1-UV showed a gradual decline across various spatial frequencies compared to SN60WF.With the increase in aperture size, the impact of IOL decentration or tilting on MTF values and USAF 1951 resolution test chart became more notable for A1-UV relative to SN60WF.Conclusions:The SN60WF IOL effectively filters blue light within the wavelength range of 400-500 nm.However, when both IOL experience decentration greater than 0.3 mm or tilting beyond 3°, the optical quality of the IOL will decline.A1-UV has a distinct advantage over SN60WF in terms of resistance to both decentration and tilting-induced optical performance degradation in vitro.
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Surgery is currently the only effective treatment for cataract.As the standard of living improves, people's demand for postoperative visual quality increases, and a variety of functional artificial lenses (IOL) have been continuously introduced.The in vitro optical quality testing system is used for the design and optimization of new IOL and for the preliminary clinical study of IOL to evaluate the effects of influencing factors such as IOL material, design, decentration, tilt, rotation, incident light wavelength and pupil diameter on the optical quality of IOL.It is helpful for doctors to fully understand and correctly select IOL. In vitro optical quality test systems mainly include optical testing platform and optical design software.The former can experimentally measure IOL, while the latter can perform optical numerical simulation of IOL. In vitro optical quality test systems have received increasing attention in China in recent years.This article reviews the in vitro optical quality test system of IOL and its clinical application.This article reviews the commonly used in vitro optical quality test systems and their clinical applications, including the measurement and evaluation indicators of in vitro optical quality, the construction of optical test platforms (OptiSpheric ? IOL PRO, Badal Optometer, PMTF, and NIMO) and the measurement principles of optical design software (ZEMAX, OSLO, and VirtualLab), as well as their applications in IOL optical quality evaluation and the limitations of in vitro optical testing.
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AIM: To evaluate clinical efficacy and safety of ultrasound cycloplasty(UCP)in the treatment of refractory glaucoma.METHODS:From June 2021 to October 2022, a total of 17 patients(17 eyes)with refractory glaucoma were enrolled in this prospective study, and they all underwent UCP. The patients underwent 6 mo followed-up post-treatment, and the intraocular pressure(IOP), pain grade score, IOP lowering drugs, success rate and occurrence of complications were documented.RESULTS:The IOP was significantly decreased from 51.98±7.80 mmHg before UCP to 32.54±13.21 mmHg at 1 d, 22.38±11.98 mmHg at 1 wk, 22.63±10.78 mmHg at 1 mo, 26.05±9.17 mmHg at 3 mo, and 23.73±9.60 mmHg at 6 mo postoperatively(all P<0.01). The percentage of IOP reduction after treatment was 36.25%, 57.10%, 56.35%, 49.16% and 54.09% at 1 d, 1 wk, 1, 3, and 6 mo, respectively. The pain grade scores were decreased(P<0.01). There was a statistically significant reduction in the use of IOP lowering medications(P=0.008). At 6 mo postoperatively, 2 eyes(12%)were complete success, 11 eyes(65%)were qualified success, and 4 eyes(24%)were failure. The main complication observed was anterior chamber inflammation in 1 eye(6%), foreign body sensation in 2 eyes(12%), subconjunctival hemorrhage in 2 eyes(12%), and conjunctival congestion in 6 eyes(35%). All symptoms spontaneously resolved within 1 wk without requiring any specific treatment. One case of choroidal detachment(6%)occurred on 10 d postoperatively, but recovered after orally treated by prednisone acetate for 1 mo. No other serious complications, such as hyphema, corectopia, synechia or macular edema were reported.CONCLUSION:UCP is safe and efficacious in treating refractory glaucoma, reducing IOP and alleviating ocular pain symptoms, while maintaining a favorable safety profile.
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AIM: To assess the repeatability and agreement of higher-order aberration obtained by adaptive optics visual simulator(VAO)compared with OPD-Scan Ⅲ.METHODS: A cross-sectional study was conducted from August to September 2023, including a total of 204 patients(204 eyes)with myopia whose right eyes were measured. The examinations were performed by the same skilled examiner using both devices separately. The VAO device was used to measure higher order aberrations of orders 3 to 6 at a pupil diameter of 4.5 mm, while both the VAO and OPD-Scan Ⅲ devices were utilized to measure total higher-order aberration(tHOA), spherical aberration(SA), coma aberration(Coma), and trefoil aberration(Trefoil)of the entire eye at pupil diameters ranging from 3 to 6 mm. Furthermore, the repeatability of whole eye aberration measurements obtained with the VAO device was evaluated and the agreement of the two devices was assessed.RESULTS: The whole-eye higher-order aberrations measured by VAO demonstrated excellent repeatability(0.767≤ICC≤0.941, Sw<0.01 μm, TRT<0.1 μm). There was no statistically significant difference in Coma measured by VAO or OPD-Scan Ⅲ for pupil diameters ranging from 4 to 6 mm(P>0.05), while a statistically significant difference was observed in whole-eye tHOA of other pupil diameters(all P<0.05). The agreement of aberration measurements for each order between VAO and OPD-Scan Ⅲ for 3 mm pupil diameters, SA at 4 and 5 mm pupil diameter and Coma at 4 mm pupil diameter showed a 95% limit of agreement(LoA)<0.1, indicating good agreement; however, poor agreement was found for the remaining aberration measurements at different pupil diameters, with a 95%LoA>0.1, and there were significant differences in higher-order aberrations measured by two devices under a pupil diameter of 3 mm(r=0.218-0.317, P<0.01), 4 mm(r=0.406-0.672, P<0.01), 5 mm(r=0.538-0.839, P<0.01 and r=0.030-0.109, P>0.01)and 6 mm(r=0.369-0.766, P<0.01).CONCLUSION: The VAO demonstrates favorable repeatability when assessing whole-eye higher order aberration under pupil diameters of 3-6 mm. However, there is inadequate agreement and interchangeability in whole-eye higher order aberration at 3-6 mm pupil diameter between VAO and OPD-Scan Ⅲ for clinical purposes.
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Objective:To systematically compare the accuracy of intraocular lens (IOL) power calculation formulas in cataract patients with shallow anterior chamber.Methods:A comprehensive literature search was conducted in MEDLINE, EMBASE, Cochrane Library, and the Chinese databases including CNKI, Wanfang, and VIP databases.The peer-reviewed literature on the accuracy of IOL power calculation formulas in cataract patients with shallow anterior chamber was searched from the establishment of the database until August 2020.Literature screening, data extraction and quality assessment were performed according to inclusion and exclusion criteria.The mean difference ( MD) of mean absolute error (MAE) among different formulas was analyzed.Meta-analysis was performed using Revman 5.3 software. Results:Seven studies involving 499 eyes were included.The accuracy of six formulas, Barrett Universal Ⅱ, Haigis, SRK/T, Hoffer Q, Holladay 1 and Holladay 2, was evaluated.The MAE of Barrett Universal Ⅱ was significantly lower than that of Hoffer Q ( MD=0.11 D; 95% CI: 0.05-0.17 D; P<0.001), Haigis ( MD=0.08 D; 95% CI: 0.03-0.13 D; P=0.002), and Holladay 2 ( MD=-0.06 D; 95% CI: -0.11--0.01 D; P=0.020). No significant difference was found in the remaining pairwise comparisons (all at P>0.05). Conclusions:The Barrett Universal Ⅱ formula is more accurate than Hoffer Q, Haigis, and Holladay 2 formulas in predicting IOL power in cataract patients with shallow anterior chamber.
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Objective:To systematically evaluate the efficacy of phacoemulsification and intraocular lens (IOL) with and without capsular tension ring (CTR) in patients with high myopia and cataract.Methods:MEDLINE, EMBASE, Cochrane Library, and Chinese databases including CNKI, Wanfang Data, and VIP databases were searched from their establishment to October 2020 to obtain peer-reviewed clinical studies comparing the efficacy of cataract phacoemulsification and IOL implantation combined with CTR implantation (experimental group) and cataract phacoemulsification and IOL implantation (control group) in patients with high myopia and cataract.Literature screening, data extraction and methodological quality assessment were implemented based on inclusion and exclusion criteria.A meta-analysis of postoperative best corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution unit, posterior capsular opacification (PCO), capsular contraction syndrome (CCS), retinal detachment (RD) was performed using Revman 5.3 software with mean difference ( MD) and odds ratio ( OR) describing the effect sizes of measurement data and count data, respectively. Results:Eight studies with 2 085 eyes were included in this study, including 1 054 eyes in the experimental group and 1 031 eyes in the control group.Meta-analysis showed that there was no significant difference in BCVA between the two groups at 1 week, 1 month, and 3 months after surgery, but the improvement in BCVA at 6 months after surgery was significantly better in the experimental group than in the control group ( MD: -0.11; 95% CI: -0.15--0.07; P<0.01). The incidence rates of postoperative PCO ( OR: 0.24; 95% CI: 0.15-0.36; P<0.01) and CCS ( OR: 0.08; 95 % CI: 0.01-0.65; P=0.02) and RD ( OR: 0.21; 95% CI: 0.05-0.82; P=0.02) were lower in the experimental group than in the control group, and the differences were statistically significant. Conclusions:The combination of CTR in the treatment of patients with high myopia and cataract can improve the postoperative visual quality and reduce the incidence of postoperative PCO, CCS and RD.
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Objective:To evaluate the difference and agreement of cycloplegic refraction between adaptive optics visual simulator (VAO) and conventional refraction methods.Methods:A diagnostic test study was conducted.Thirty-one eyes of 31 healthy subjects including 15 males and 16 females were enrolled in November, 2019 in Affiliated Hospital of North Sichuan Medical College.Mean age of the subjects was (20.1±1.0) years, and the right eye was taken for data analysis.Cycloplegic refraction was measured by VAO and conventional refraction methods, respectively.Spherical power, cylindrical power, Jackson cross-cylinder power at axis 90° and 180° (J 0) and Jackson cross-cylinder power at axis 45° and 135° (J 45) vector powers were recorded.Paired t-test was used to compare the refractive parameters between different refraction methods, and the intraclass correlation coefficient (ICC) and Bland-Altman plots were used to evaluate the agreement between VAO and conventional refraction methods.This study adhered to the Declaration of Helsinki, and the research protocal was approved by an Ethics Committee of Affiliated Hospital of North Sichuan Medical College (No.2020ER[A]018). Written informed consent was obtained from each subject prior to any medical examination. Results:For subjective refraction, the ICC for spherical power, cylindrical power, J 0 and J 45 between VAO and phoropter were 0.97, 0.75, 0.84 and 0.09, respectively.For objective refraction, the ICC for spherical power, cylindrical power, J 0 and J 45 between VAO and autorefractor were 0.98, 0.70, 0.74 and 0.61, respectively.The mean differences in spherical power, cylindrical power, J 0 and J 45 between VAO and phoropter were (0.05±0.32), (-0.23±0.28), (-0.10±0.14) and (-0.04±0.16)D, respectively, and the differences in cylindrical power and J 0 were statistically significant (both at P<0.01), whereas no significant differences in spherical power and J 45 were found ( P=0.41, 0.18). The mean differences in spherical power, cylindrical power, J 0 and J 45 measured by VAO and autorefractor were (-0.70±0.26), (-0.07±0.46), (-0.03±0.27) and (0.01±0.12)D, respectively, and the spherical power measurement by VAO was significantly more negative than the autorefractor ( t=15.09, P<0.01), while no significant differences in cylindrical power, J 0 and J 45 were found ( P=0.39, 0.59, 0.63). No significant difference values in spherical power, cylindrical power, J 0 and J 45 were found between the two objective refraction methods and phoropter subjective refraction (all at P>0.05). Conclusions:With cycloplegia, spherical power obtained by VAO objective refraction is more negative compared with autorefractor.There is a good agreement of spherical power and astigmatism vector values measured by VAO and phoropter subjective refraction, and the measurement differences are clinically acceptable.
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Adaptive optics (AO) can measure and correct wavefront aberrations in real time, which enables the optical system to adapt to external changes and maintain excellent optical performance, and has been gradually paid attention in the field of ophthalmology.AO technology can carry out optometry according to wavefront aberrations to improve the efficiency and accuracy of subjective and objective refraction, eliminate the influence of ocular aberrations on retinal imaging, provide more accurate data for the evaluation of optic nerve function, improve the effectiveness of visual perception training and provide vision care and treatment for special people, as well as simulate and predict postoperative visual outcome and give personalized schemes for refractive surgery and intraocular lens implantation.Moreover, AO combined with optical coherence tomography, optical scanning laser ophthalmoscope, and confocal scanning laser ophthalmoscope, can realize fundus imaging and retinal vascular imaging in real time, provide better sensitivity and resolution of retinal detection, distinguish fine details of retinal vessels and cone cells, and characterize retinal pigment epithelium topology and deformation, the application of which in posterior segment laser surgery, glaucoma diagnosis and follow-up, color blindness and retinal physiological activity research has been attracting attention.In this article, the principle and application of AO in ophthalmology were briefly reviewed.
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Objective:To investigate the repeatability and correlation in tilt and decentration measurement of crystalline lens and intraocular lens (IOL) under non-mydriatic and mydriatic conditions using swept-source ocular coherence tomography CASIA2.Methods:A diagnostic test study was conducted.A total of 109 cataract patients (157 eyes) who received phacoemulsification with IOL implantation surgery in the Affiliated Hospital of North Sichuan Medical College from March to July 2020 were enrolled.The decentration and tilt of crystalline lens and IOL under non-mydriatic and mydriatic conditions were measured for three times by a single examiner using CASIA2 before and one week after surgery.The 0.5% compound tropicamide eye drops were used to dilate.Repeatability was evaluated by within-standard deviation, test-retest repeatability (TRT), coefficient of variation (CoV) and intraclass correlation coefficient (ICC). The correlation in decentration and tilt of crystalline lens and IOL between before and after mydriasis was assessed by Pearson correlation coefficient.This study adhered to the Declaration of Helsinki, and the study protocol was approved by an Ethics Committee of the Affiliated Hospital of North Sichuan Medical College (No.2020ER030-1). Written informed consent was obtained from all subjects before any medical examination.Results:The decentration of crystalline lens under non-mydriatic and mydriatic conditions was (0.217±0.112)mm and (0.220±0.110)mm, respectively, and the tilt was (5.017±1.422)° and (5.310±1.645)°, respectively.The decentration of IOL under non-mydriatic and mydriatic conditions was (0.245±0.136)mm and (0.250±0.145)mm, respectively, and the tilt was (5.144±1.345)° and (5.437±1.646)°, respectively.No significant difference was found between non-mydriatic and mydriatic conditions (all at P>0.05). Under both non-mydriatic and mydriatic conditions, the crystalline lenses of both eyes decentered and tilted toward the inferotemporal direction, and the IOL of right eyes decentered toward the inferior and tilted toward the inferotemporal direction, and the IOL of left eyes decentered and tilted toward the inferotemporal direction.Except the crystalline lens decentration, the measurement repeatability of crystalline lens tilt, IOL decentration and tilt in cataract patients before and after mydriasis was good, with ICC range in 0.815-0.984, TRT<50% and CoV≤14.840%.The measurement repeatability of crystalline lens decentration was poor, and the measurement repeatability of decentration axis, tilt and tilt axis of crystalline lens, and the repeatability of decentration and tilt of IOL were good in both eyes, with ICC range in 0.757-0.998, TRT<50% and CoV≤17.763%.There were good correlations in decentration, decentration axis, tilt and tilt axis of crystalline lens and IOL between non-mydriatic and mydriatic conditions (all r≥0.679, all at P<0.01). Conclusions:The measurement repeatability of decentration axis, tilt and tilt axis of crystalline lens and IOL, as well as the decentration of IOL by CASIA2 before and after mydriasis is good.The correlations of the measured parameters before and after mydriasis are good.
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Although binocular vision problems do not appear to be one of the common complications of refractive surgery, the available evidence suggests that these problems can occur after refractive surgery, and preoperative binocular vision status may predict the risk of postoperative binocular vision anomalies.Furthermore, because ophthalmologists usually do not clearly recognize binocular vision, or they do not pay enough attention to it, the existing literature may underestimate the actual prevalence of binocular vision problems after refractive surgery.This paper discusses the existing literature on refractive surgery-related binocular vision anomalies and recommends a screening protocol and risk stratification.It also discusses the expected results of binocular vision testing, the diagnostic criteria for common binocular vision problems, and strategies for treating these anomalies before and after refractive surgery.
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Although binocular vision problems do not appear to be one of the common complications of refractive surgery,the available evidence suggests that these problems can occur after refractive surgery,and preoperative binocular vision status may predict the risk of postoperative binocular vision anomalies.Furthermore,because ophthalmologists usually do not clearly recognize binocular vision,or they do not pay enough attention to it,the existing literature may underestimate the actual prevalence of binocular vision problems after refractive surgery.This paper discusses the existing literature on refractive surgery-related binocular vision anomalies and recommends a screening protocol and risk stratification.It also discusses the expected results of binocular vision testing,the diagnostic criteria for common binocular vision problems,and strategies for treating these anomalies before and after refractive surgery.
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Objective@#To evaluate the repeatability and reproducibility of swept-source optical coherence tomography biometrics (Tomey OA-2000) for measuring the biological parameters of the eyeballs in healthy people.@*Methods@#A diagnostic test was carried out in this study.One hundred and three healthy volunteers who were recuited from July to September 2018 in Affiliated Hospital of North Sichuan Medical College were included, and the right eyes were examined.Two examiners used OA-2000 for 3 consecutive measurements, respectively.One week later, the first examiner used OA-2000 for 3 consecutive measurements.The ocular biological parameters including axial length (AL), anterior chamber depth (ACD), corneal curvature (K), lens thickness (LT), central corneal thickness (CCT), pupil diameter (PD), and white to white (WTW) were measured.The repeatability and reproducibility of each parameter based on within-subject standard deviation (SW), repeatability limit of standard deviation (2.77SW), coefficient of variation (CoV) and intra-class correlation coefficient (ICC) was evaluated.This study followed the Declaration of Helsinki.This study protocol was approved by Ethic Committee of the Affiliated Hospital of North Sichuan Medical College (No.2018ER[A]019).@*Results@#Of the ocular biological parameters measured by OA-2000, CoV was less than 2% while ICC was greater than 0.950, except PD and WTW.The repeatability and reproducibility of K, AL and ACD were all good.For K1(ø=2.5 mm and 3.0 mm), the SW was less than 0.120 D, the 2.77SW was less than 0.350 D, the CoV was less than 0.293%, and the ICC was greater than 0.990; For K2 (ø = 2.5 mm and 3.0 mm) , the SW were less than 0.175 D, the 2.77SW were less than 0.485 D, the CoV was less than 0.396%, the ICC was greater than 0.980; for Km (ø = 2.5 mm and 3.0 mm), the SW were less than 0.099 D, 2.77SW were less than 0.275 D, CoV was less than 0.227%, ICC was greater than 0.996; ACD SW was less than 0.024 mm, 2.77SW was less than 0.066 mm, CoV was less than 0.668%, ICC were greater than 0.993; the SW of AL was less than 0.014 mm, the 2.77SW was less than 0.038 mm, the CoV was less than 0.057%, and all of the ICCs were 1.000.@*Conclusions@#Except PD and WTW, the ocular biological parameters measured by OA-2000 have good repeatability and reproducibility, in which the accuracy of AL measurement is the highest.
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Recently,optical biometers based on swept-source optical coherence tomography (SS-OCT) technology have been applied to clinical ophthalmology.Compared with previous optical biometers,SS-OCT instruments have many advantages,such as faster processes,more accurate results,higher detection rate,and more built-in formulas for calculating the intraocular lens (IOL) power;moreover,SS-OCT images can be used to detect preliminary maculopathy and predict postoperative tilt of IOL.In this paper,we reviewed the application of SS-OCT biometer in cataract,mainly focus on the principle of work,the evaluation of repeatability and reproducibility,the consistency comparison with other biometers,and the application of SS-OCT in other aspects of cataract.
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With the improvement of cataract examination methods,intraocular lens (IOL) design and process,surgical equipments and techniques,cataract surgery was gradually developed from vision rehabilitation to refractive surgery.Therefore,the assessment of visual quality is getting more attention.Clinically,in addition to the extension of concept of visual acuity,contrast sensitivity function (CSF),modulation transfer function (MTF),point spread function (PSF),wavefront aberration and scattering index are also used,with a view to making a comprehensive assessment of visual quality of cataract patients preoperatively and postoperatively.Ophthalmologists should pay attention to the methods and results of evaluation on the visual quality,to provide support for the design of personalized surgery and the improvement of visual quality.
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The evaluation of visual quality about human eyes has always been an important issue in the field of eye science and visual optics,and it is mainly divided into subjective evaluation method and objective evaluation method,evaluation indicators including visual acuity,contrast sensitivity,wavefront aberration and retinal straylight,and so on.In addition,according to different principles and standards,visual system imaging quality evaluation methods can also be divided into visual refractive system and retinal nerve system evaluation,geometrical optics and physical optics evaluation,static and dynamic visual function evaluation.The selection of visual quality evaluation method should be considered from multiple dimensions on comprehensive consideration.in recent years,the improvement of quality of life promotes the development of visual quality assessment methods,and more attention is paid to the evaluation of continuous functional visual acuity.This article reviews the research progress of visual quality assessment methods.