AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients ...AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients diagnosed with mild KCN.Objective dry retinoscopy using autorefractometer and subjective refraction measurements were performed.Sphere,cylinder,J0,J45,and spherical equivalent values were compared between the two techniques.RESULTS:The mean age of 68 patients with mild KCN was 21.32±5.03y(12–35y).There were 37(54.4%)males.Objective refraction yielded significantly more myopic sphere(-1.44 D vs-0.57 D),higher cylinder magnitude(-2.24 D vs-1.48 D),and more myopic spherical equivalent(-2.56 D vs-1.31 D)compared to subjective refraction(all P<0.05).The mean differences were-0.87 D for sphere,-0.76 D for cylinder,and-1.25 D for spherical equivalent.No significant differences were found for J0 and J45 values,indicating agreement in astigmatism axis(P>0.05).CONCLUSION:In patients with mild KCN,objective dry retinoscopy overestimates the degree of myopia and astigmatism compared to subjective refraction.The irregular cornea in KCN likely impacts objective measurements.Subjective refraction allows compensation for irregularity,providing a more accurate correction.When determining refractive targets,the tendency of objective methods to overcorrect should be considered.展开更多
AIM:To compare the subjective refraction data with autorefraction findings in high astigmatisms.METHODS:In a cross-sectional study,sampling was done from in different geographic regions in Iran using a multistage rand...AIM:To compare the subjective refraction data with autorefraction findings in high astigmatisms.METHODS:In a cross-sectional study,sampling was done from in different geographic regions in Iran using a multistage random cluster sampling method.All study participants underwent cycloplegic auto-refraction and subjective refraction using the red-green test.RESULTS:In this study,277 eyes of 158 students aged 8 to 15y were analyzed.According to the results,the mean difference between subjective refraction and autorefraction in measuring sphere,cylinder,spherical equivalent,J0,and J45 was-0.18±0.76,-0.36±0.40,-0.36±0.79,0.15±0.20,and 0.05±0.21 respectively.The correlation of these two refraction methods in measuring the aforementioned indices was 0.963,0.898,0.960,0.931,and 0.948 respectively.The 95%limits of agreement of the two methods in measuring the above indices were-1.66 to 1.31,-1.14 to 0.42,-1.91 to 1.19,-0.24 to 0.54,and-0.36 to 0.47 respectively.The agreement between the two methods decreased with increasing cylinder power,and the best agreement was found in myopic individuals.CONCLUSION:The measurements obtained by autorefractometer have a significantly higher cylinder average compared to subjective refraction.However,in the cylinder range of 4–5 diopters,the values of J0 and J45 do not have a high correlation.展开更多
The emergent metagrating,with its unique and flexible beam shaping capabilities,offers new paths to efficient modulation of acoustic waves.In this work,an acoustic metagrating is demonstrated for high-efficiency and w...The emergent metagrating,with its unique and flexible beam shaping capabilities,offers new paths to efficient modulation of acoustic waves.In this work,an acoustic metagrating is demonstrated for high-efficiency and wide-angle anomalous refraction.It is shown that the normal reflection and transmission can be totally suppressed by properly modulating the amplitude and phase characteristics of the metagrating supercells for high-efficiency anomalous refraction.The anomalous refraction behavior is achieved in the wide range of incident angles from 28°to 78°,and the efficiency of-1st order diffraction is higher than 90%by finely designing the metagrating structure.The anomalous refraction behaviors are verified experimentally at incidence angle of 28°,45°,and 78°,respectively.The demonstrated metagrating is anticipated to possess efficient wide-angle composite wavefront engineering applications in such fields as communications.展开更多
AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 e...AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 emmetropia(E),429 low myopia(LM),80 moderate myopia(MM),and 32 low hypermetropia(LH)]aged 10 to 13y were analyzed.RPRs were measured using MRT without mydriasis.MRT results showed RPR at 0-15°(RPR 0-15),15°-30°(RPR 15-30),and 30°-45°(RPR 30-45)annular in the inferior(RPR-I),superior(RPR-S),nasal(RPR-N),and temporal(RPR-T)quadrants.Spherical equivalent(SE)was detected and calculated using an autorefractor.RESULTS:There were significant differences of RPR 15-30 between groups MM[0.02(-0.12;0.18)]and LH[-0.13(-0.36;0.12)](P<0.05),MM and E[-0.06(-0.20;0.10)](P<0.05),and LM[-0.02(-0.15;0.15)]and E(P<0.05).There were also significant differences of RPR 30-45 between groups MM[0.45(0.18;0.74)]and E[0.29(-0.09;0.67)](P<0.05),and LM[0.44(0.14;0.76)]and E(P<0.001).RPR values increased from the hyperopic to medium myopic group in each annular.There were significant differences of RPR-S between groups MM[-0.02(-0.60;0.30)]and E[-0.44(-0.89;-0.04)](P<0.001),and LM[-0.28(-0.71;0.12)]and E(P<0.05).There were also significant differences of RPR-T between groups MM[0.37(0.21;0.78)]and LH[0.14(-0.52;0.50)](P<0.05),LM[0.41(0.06;0.84)]and LH(P<0.05),and LM and E[0.29(-0.10;0.68),P<0.05].A Spearman’s correlation analysis showed a negative correlation between RPR and SE in the 15°-30°(P=0.005),30°-45°(P<0.05)annular(P=0.002),superior(P<0.001),and temporal(P=0.001)quadrants.CONCLUSION:Without pupil dilation,values for RPR 15-30,30-45,RPR-S,and T shows significant differences between myopic eyes and emmetropia,and the differences are negatively correlated with SE.展开更多
AIM:To evaluate the refraction difference value(RDV)variations in children and adolescents with different refractive errors and analyze its correlation with refractive development.METHODS:Participants aged 4-16y with ...AIM:To evaluate the refraction difference value(RDV)variations in children and adolescents with different refractive errors and analyze its correlation with refractive development.METHODS:Participants aged 4-16y with different refractive statuses(hyperopia,emmetropia,myopia)underwent comprehensive eye examinations,including spherical equivalent(SE)refraction,axial length(AL),total RDV(TRDV),and RDVs at various eccentricities(0°-15°,15°-30°,30°-45°)and quadrants(inferior,superior,nasal,temporal).Statistical analysis involved one-way ANOVA for group comparisons and Pearson correlation for examining relationships between SE/AL and RDVs.Paired t-tests compared quadrant-specific RDVs within groups.RESULTS:Significant difference was found in TRDV(P<0.001),RDV15°-30°(P=0.033),RDV30°-45°(P<0.001),RDV-inferior(RDV-I,P<0.001)and RDV-temporal(RDV-T,P<0.001)among hyperopia,emmetropia and myopia group.Pearson correlation analysis revealed a negative correlation of SE with TRDV(P=0.001),RDV30°-45°(P=0.004),RDV-I(P=0.047),and RDV-T(P<0.001).The differences between RDV-superior(RDV-S)and RDV-I were statistically significant in all groups(P<0.001 for all)and between RDV-T and RDV-nasal(RDV-N)were statistically significant in hyperopia group(P<0.001).Within the premyopic group,the analysis revealed a negative correlation of SE with RDV-I(P=0.009).Pearson correlation analysis revealed a positive correlation of AL with TRDV(P=0.036),RDV15°-30°(P=0.004),RDV30°-45°(P<0.001),RDV-S(P=0.003),RDV-I(P<0.001),RDV-T(P<0.001),RDV-N(P=0.022),while revealed a negative correlation of AL with RDV0-15°(P=0.018).CONCLUSION:Our study indicates TRDV,RDV30°-45°,RDV-I,RDV-T may relate to refractive development,and a negative correlation between SE and RDV-I in pre-myopic children.展开更多
Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are...Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.展开更多
Acoustic emission(AE)localization algorithms based on homogeneous media or single-velocity are less accurate when applied to the triaxial localization experiments.To the end,a robust triaxial localization method of AE...Acoustic emission(AE)localization algorithms based on homogeneous media or single-velocity are less accurate when applied to the triaxial localization experiments.To the end,a robust triaxial localization method of AE source using refraction path is proposed.Firstly,the control equation of the refraction path is established according to the sensor coordinates and arrival times.Secondly,considering the influence of time-difference-of-arrival(TDOA)errors,the residual of the governing equation is calculated to estimate the equation weight.Thirdly,the refraction points in different directions are solved using Snell’s law and orthogonal constraints.Finally,the source coordinates are iteratively solved by weighted correction terms.The feasibility and accuracy of the proposed method are verified by pencil-lead breaking experiments.The simulation results show that the new method is almost unaffected by the refraction ratio,and always holds more stable and accurate positioning performance than the traditional method under different ratios and scales of TDOA outliers.展开更多
The article develops coordinate-invariant methods to calculate reflection and refraction of plane monochromatic waves at the plane boundary between two isotropic and an isotropic and an anisotropic medium. The vectori...The article develops coordinate-invariant methods to calculate reflection and refraction of plane monochromatic waves at the plane boundary between two isotropic and an isotropic and an anisotropic medium. The vectorial wave equation for the electric field is used to determine polarization vectors to known refraction vectors and this is applied to uniaxial media. Then it is shortly shown how the boundary conditions can be derived using the Heaviside step function and its derivatives which are the delta function and its derivatives. As preparation to the anisotropic case, there are calculated in coordinate-invariant way the amplitude relations for the reflection and refraction between two isotropic media and then in analogous way, the case of reflection and refraction between an isotropic and an anisotropic medium. This is then specialized for perpendicular incidence. It is shown that negative refraction such as discussed in last twenty-five years is impossible.展开更多
Introduction: Refractive errors in school children continue to receive less attention and priority in many developing countries. Refractive errors can be a source of poor vision and disinterest in school. The aim of t...Introduction: Refractive errors in school children continue to receive less attention and priority in many developing countries. Refractive errors can be a source of poor vision and disinterest in school. The aim of this study was to describe the epidemiological and clinical characteristics of ametropia in school children. Materials and Methods: This was a descriptive cross-sectional study carried out at the International Ophthalmology Center of Mali covering the period from January 1 to June 30, 2024, involving all school children. Results: A total of 207 children out of 702 school children received during the study period presented refractive errors. The most affected age group was 16 - 20 years old, with an average age of 16.95 years. The female sex was the majority, with 77.2% compared to 22.2% for the male sex. The main reasons for consultation were visual fatigue (36.2%) and tearing (20.2%). Hyperopia astigmatism was the most common refractive error, with a frequency of 62.3%. Low ametropia (Discussions: The management of refractive errors in school children is a major factor in their educational success. Conclusion: Early detection and management of refractive needs in school children can be key elements allowing them to be more efficient in daily activities.展开更多
As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL pow...As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice.展开更多
AIM:To analyze the two-year visual and refractive outcomes as well as the safety,and efficacy of photorefractive keratectomy(PRK)surgery for myopia.METHODS:In this prospective cohort study,63 eligible patients were re...AIM:To analyze the two-year visual and refractive outcomes as well as the safety,and efficacy of photorefractive keratectomy(PRK)surgery for myopia.METHODS:In this prospective cohort study,63 eligible patients were recruited,including 45 women(71.4%)and 18 men(28.6%).Demographic characteristics along with pre-and post-operative clinical data including visual acuity,refraction,maximum ablation,spherical and cylindrical error,and residual stromal bed(RSB)were evaluated.RESULTS:The mean age of the patients was 35.42±8.16y(range 22 to 55y).The mean spherical and cylindrical error before surgery were-2.23±1.58 D(range-5 to+0.25)and-1.24±0.94 D,respectively(range-3.75 to 0.00).The mean efficacy and safety of PRK surgery at 2y follow-up were 0.98±0.06 and 1.01±0.04 respectively.The lower age was significantly correlated with a higher amount of efficacy index(P<0.001,r=-0.42).Also,the lower amount of preoperative myopia and spherical equivalent(SE)were correlated with a higher safety index(P<0.001,r=-0.44;P<0.001,r=-0.46).CONCLUSION:The two-year efficacy and safety of PRK for the treatment of low myopia is excellent.Younger age and lower amount of refractive error are correlated with higher efficacy and safety indices of the surgery.展开更多
Based on optofluidics and whispering gallery mode(WGM)theory,here an optofluidic refractive index sensor with microtube-coupled suspended core fiber(SCF)is proposed.It solves the issues of general sensors with microca...Based on optofluidics and whispering gallery mode(WGM)theory,here an optofluidic refractive index sensor with microtube-coupled suspended core fiber(SCF)is proposed.It solves the issues of general sensors with microcavity-coupled fiber taper such as too fragile,unstable performance due to open coupling,poor portability and repeatability,while overcoming the poor performance of low refractive index sensing in general full-package fiber sensors.The sensor only needs a very small amount of liquid sample(about 1.8 nL).The proposed sensor combines the excellent performance of full package,optofluidics and WGM resonator.The resonant characteristics and sensing performance of the sensor are analyzed and discussed by the theoretical simulation.The simulation results indicate that the sensor has a wide refractive index sensing range(1.330-1.700)and good performance.The resonance wavelength shift has a good linear relationship with the liquid refractive index variation.In the low refractive index region,the sensitivity is 222.5-247.5 nm/RIU,Q-factor is 1.03×10^(3) and the detection limit is 3.64×10^(-4) RIU.In the medium and high refractive index regions,the sensitivity is 564.4-846.2 nm/RIU,Q-factor is up to 8.62×10^(4),and the detection limit can be as low as 1.29×10^(-6) RIU.The sensor exhibits a high sensitivity,a high Q-factor and a very low detection limit.展开更多
AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 hea...AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 healthy 3-week-old rabbits were randomly assigned to one of the four groups with 8 in each group for 12wk:Control group(NC)under low blue light(output ratio of blue light 1.8%)at low illuminance(341 lx),HI group under low blue light(output ratio of blue light 1.6%)at high illuminance(5057 lx),simulating natural light(S-NL)group under high blue light(output ratio of blue light 4.9%)at high illuminance(5052 lx),and MB group under high blue light(output ratio of blue light 5.2%)at low illuminance(342 lx).The lighting in each group were provided by light emitting diode(LED)lamps emitting visible light(range 380-780 nm)in addition to(or not)LED lamps only emitting short wavelength(range 380-500 nm).Refraction,axial length,and corneal curvature radius were assessed by retinoscopy,ultrasonography and keratometry,respectively.Average data of both eyes for each animal were used as single values and compared among groups.RESULTS:During the 12-week intervention,all animals had an emmetropization period.The decrease of refraction in rabbits in HI group was similar to S-NL group,both slower than that of NC group(P<0.001).At the 12th week,the refraction(3.000±0.267 D)and vitreous cavity depth(7.421±0.168 mm)of S-NL was similar to HI group(3.250±0.267 D,7.264±0.256 mm),significantly different from NC group(1.937±0.291 D,7.825±0.313 mm;P<0.001 for both).High blue light at low illuminance had little effect on refraction change.At the end of intervention,the difference of refraction(2.219±0.281 D)and vitreous cavity depth(7.785±0.229 mm)in MB group were not statistically significant(P=0.311,P=0.749)compared with NC group.The other components were less affected by lighting conditions(P>0.05).CONCLUSION:The light levels per se but not the rich in spectral content of short wavelengths determine the inhibitory effect of ambient lighting on myopia development in rabbits.展开更多
A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electro...A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.展开更多
AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.De...AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.Demographic data,refractive error,best-corrected distance visual acuity(BCVA),and the horizontal and vertical angle of deviation between basic esotropia and exotropia patients were compared.RESULTS:Among the 7129 patients(mean age 22.98±14.81y)evaluated,44.7%(3185 cases,54.9%male)exhibited basic-type esotropia,while 55.3%(3944 cases,53.9%male)presented with basic-type exotropia.Basic esotropia cases exhibited more hyperopic spherical equivalent measurements in both eyes(right:0.53±3.07 vs left:0.56±2.98 D)than those with basic exotropia(right eye:-0.33±2.84 vs left eye:-0.24±2.68 D,P<0.001 for both eyes).Patients with basic esotropia had significantly greater horizontal deviation angles(near:36.08±18.87 PD and far:35.56±18.75 PD)compared to those with basic exotropia(near:33.75±16.11 PD and far:33.26±15.90 PD,P<0.001).Conversely,patients with basic exotropia had slightly higher vertical deviation angles(near:1.67±5.80 PD and far:1.72±5.89 PD)compared to those with basic esotropia(near:1.12±4.57 PD and far:1.12±4.58 PD,P<0.001).Patients with basic esotropia underwent surgical intervention at younger ages compared to basic exotropia individuals(19.68±15.99 vs 25.66±13.20,P<0.001).CONCLUSION:Basic esotropia patients present more hyperopic refractive errors,better visual acuity,larger horizontal yet smaller vertical ocular misalignments,and tend to undergo strabismus surgery at younger ages relative to basic exotropia cases.展开更多
AIM:To analyze ocular parameters and refractive status in children aged 3-12y and to explore differences in these parameters across age groups with identical refractive status for studying refractive progression.METHO...AIM:To analyze ocular parameters and refractive status in children aged 3-12y and to explore differences in these parameters across age groups with identical refractive status for studying refractive progression.METHODS:Demographic characteristics,cycloplegic refraction data,and ocular parameters of the participants were collected.Changes in ocular parameters were described according to different age groups.After adjusting for refractive factors,the relationship between age and ocular parameters was explored.Standard regression coefficients(β)obtained from multiple linear regressions were used to compare the magnitude of the effect of age on the parameters and ocular components on refractive power.RESULTS:Data were collected from the right eyes of 1504 participants.Lens thickness(LT)decreased with age,whereas the axial length(AL)and anterior chamber depth(ACD)increased.In the high-hyperopia group,changes in age were only associated with AL and LT.In the low-myopia group,the increase in age was also associated with corneal astigmatism.In the overall model,theβvalue for LT was the highest at 0.41,whereasβfor ACD and AL was significant in all groups except for the high-hyperopia group.Theβvalue of the LT on refractive power in children was slightly greater in the low age group than in the high age group.CONCLUSION:Among children with the same refractive status,the older the age,the longer the axis length and the thinner the lens.The lens affected refractive power in children in the younger age group more than in the older age group.The ocular parameter most affected by age was LT.展开更多
AIM:To report the refractive and surgical outcomes of scleral buckling(SB)with or without pars plana vitrectomy(PPV)in patients with pseudophakic rhegmatogenous retinal detachment(PRRD).METHODS:A consecutive case seri...AIM:To report the refractive and surgical outcomes of scleral buckling(SB)with or without pars plana vitrectomy(PPV)in patients with pseudophakic rhegmatogenous retinal detachment(PRRD).METHODS:A consecutive case series of patients with pseudophakia who underwent retinal detachment(RD)surgery was enrolled.The SB procedures were selected to initially treat primary pseudophakic PRRDs and SB-PPV for more complex cases,according to preoperative findings.Eyes with anterior chamber intraocular lens,proliferative vitreoretinopathy anterior to equator,previous invasive glaucoma surgery,severe degenerative myopia or macular hole,and<6mo follow-up were excluded from outcomes analysis.The primary clinical outcome measures were the single surgery anatomic success(SSAS)and final surgery anatomic success(FSAS)rates.Secondary outcome measures were postoperative visual acuity and refractive error.RESULTS:A total of 81 consecutive patients(81 eyes)were enrolled for analysis,comprising 66(81%)men and 15(19%)women with a mean age of 58y(range,33-86y)and the mean final follow-up period was 21.0±19.6mo.A total of 62 PRRDs(n=62;76.5%)were repaired with an initial SB,and 19 PRRDs(n=19;23.5%)were repaired with a combined SB-PPV.The SSAS and FSAS rates were 92.6%(75/81)and 100%(81/81),respectively.All initial failures had retinal reattachment after the secondary PPV.The mean final postoperative best-corrected visual acuity(BCVA)was 0.42±0.33 logMAR(visual acuity 20/55)and final mean refractive error was-1.48±1.40 diopters.The patients who underwent initially SB-PPV had a significantly longer duration of RD and a higher giant retinal tear rate(P<0.05)preoperatively.SSAS was 56/62(90.3%)and 19/19(100%),and the mean postoperative refractive error was-1.30±1.32 D and-1.53±1.38 D for the patients in the SB and SB-PPV groups,respectively.There was no statistically significant difference for those who had SSAS and postoperative refractive errors between the 2 groups.The postoperative BCVAs of the patients with SSAS were not significantly better in the SB group(median,20/40)than in the SB-PPV group(median 20/50).In the SB group,patients with macula-on had better visual acuity postoperatively than patients with macula-off(P=0.000).CONCLUSION:The initial surgical procedures of SB with or without PPV according to the preoperative findings achieve a high reattachment rate and an acceptable refractive error for primary pseudophakic RRD management.展开更多
AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students usin...AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students using simple random sampling.Objective refraction,ocular alignment,vergence and accommodative performance were measured and assessed in all participants.Data on QOL were collected using the College of Optometrists in Vision Development-Quality of Life(COVD-QOL)Questionnaire.The effect of mentioned parameters on the QOL were evaluated.RESULTS:Totally 726 students with mean age of 21.35±1.88y were evaluated in this study,51.5%of whom were female.Esophoria was caused significantly lower QOL in the domains of somatic symptoms and occupationalphysical symptoms(P<0.05);Besides,esotropia decreased QOL in domains of somatic symptoms P=0.002 and psychological factors(P=0.023).Students with accommodation insufficiency experienced more symptoms in all domains(P<0.05)except for psychological factors(P=0.07).Increasing in the near point of convergence and accommodation and decreases QOL and increasing accommodative facility increases QOL(all P<0.05).Myopia and astigmatism cause decrease in QOL(both P<0.05),but hyperopic students had better QOL in comparison with others(P<0.05).CONCLUSION:Screening programs and treatment of refractive errors and binocular vision anomalies,especially phoria and accommodative insufficiency,positively impact the QOL and academic achievements of university students.展开更多
AIM:To compare the changes in preschool refractive status,ocular biological parameters,and higher-order aberrations in children with retinopathy of prematurity(ROP)after retinal laser photocoagulation or anti-vascular...AIM:To compare the changes in preschool refractive status,ocular biological parameters,and higher-order aberrations in children with retinopathy of prematurity(ROP)after retinal laser photocoagulation or anti-vascular endothelial growth factor(anti-VEGF)treatment and explore their underlying factors.METHODS:This observational study involved 118 eyes of 59 children,aged 3 to 6y,with ROP followed up between March 2023 and October 2024.They were divided into the laser,anti-VEGF,and anti-VEGF+laser groups.The laser group received a single session of laser photocoagulation.The anti-VEGF group received a single anti-VEGF treatment.The anti-VEGF+laser group received a single anti-VEGF treatment after birth followed by supplementary laser treatment within 2wk to 6mo.Ocular biological parameters were measured using IOL Master 700 and Pentacam HR.Right-eye higher-order aberrations were measured using the OPD-Scan III.Best-corrected visual acuities(BCVA),refractive statuses,ocular biological parameters,and higherorder aberrations were assessed and compared.Multiple linear regression analysis was conducted to evaluate the relationships among ocular biological parameters,higherorder aberrations,spherical equivalent(SE),and treatment methods.Pearson’s correlation coefficients were used to assess the relationships between the SE and higher-order aberrations.RESULTS:The laser group had a higher incidence of myopia and a lower SE than the anti-VEGF group.The incidence of astigmatism and cylindrical power were significantly lower for the anti-VEGF than for the laser and anti-VEGF+laser groups(P<0.05).The anterior corneal surface astigmatism was higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The anterior corneal surface K2 and lens thickness were higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The whole-eye higher-order aberration root mean square(RMS)values for the right eye were significantly higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The whole-eye trefoil RMS values for the right eye were also significantly higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group(P<0.05).Laser treatment was significantly associated with SE,anterior corneal surface curvature and astigmatism,lens thickness,whole-eye highorder aberrations,and whole-eye trefoil(all P<0.05).CONCLUSION:Children with ROP who received laser treatment have higher myopia and astigmatism than those who received anti-VEGF treatment.Children treated with laser or supplementary laser treatment have higher anterior corneal astigmatism,anterior corneal curvature,thicker lenses,whole-eye higher-order aberrations,and whole-eye trefoil.The cause of myopia in children with ROP after laser treatment is increased anterior corneal surface curvature and lens thickness.展开更多
AIM:To evaluate the effect of different monochromatic lights on the refractive status and the secretion levels of neurotransmitters in the progressive myopic model of guinea pigs.METHODS:Guinea pigs(n=90)underwent dif...AIM:To evaluate the effect of different monochromatic lights on the refractive status and the secretion levels of neurotransmitters in the progressive myopic model of guinea pigs.METHODS:Guinea pigs(n=90)underwent different monochromatic lights irradiation for two weeks were randomly divided into 6 groups:white light(control),ultraviolet(UV),blue,green,red,and simulative sunlight(simSUN).The refractive status and axial length(AL)were measured.Transmission electron microscopy,Masson’s trichrome staining and hematoxylin-eosin staining were performed to observe the structural changes of retina and sclera.High-performance liquid chromatography(HPLC),western blotting and immunofluorescence were used to measure neurotransmitters and their receptors.RESULTS:Myopia models were established successfully.When compared the degrees of change in myopic eyes of control group,the UV group showed a minor decrease in AL and refraction,along with a significant increase in scleral thickness.In contrast,the red and green groups revealed a net increase in AL and refraction,coupled with a net decrease in scleral thickness(all,P<0.01).The dopamine concentration increased in the UV group,while concentrations of serotonin and melatonin significantly decreased(all,P<0.01).The groups that were exposed to UV,blue and simSUN,the expression of dopamine receptor D2(DRD2)increased,and the expression of hydroxytryptamine receptor 2A(HTR2A)and melatonin receptor type 2(MT2)decreased significantly when compared to the control group(all P<0.01).CONCLUSION:Exposure to short-wavelength light could slow the development of myopia by promoting the production of dopamine and suppressing the serotonin and melatonin concentration.The neurotransmitter receptors MT2,DRD2,and HTR2A in the sclera appear to play different roles by different color lights in myopic guinea pigs.展开更多
文摘AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients diagnosed with mild KCN.Objective dry retinoscopy using autorefractometer and subjective refraction measurements were performed.Sphere,cylinder,J0,J45,and spherical equivalent values were compared between the two techniques.RESULTS:The mean age of 68 patients with mild KCN was 21.32±5.03y(12–35y).There were 37(54.4%)males.Objective refraction yielded significantly more myopic sphere(-1.44 D vs-0.57 D),higher cylinder magnitude(-2.24 D vs-1.48 D),and more myopic spherical equivalent(-2.56 D vs-1.31 D)compared to subjective refraction(all P<0.05).The mean differences were-0.87 D for sphere,-0.76 D for cylinder,and-1.25 D for spherical equivalent.No significant differences were found for J0 and J45 values,indicating agreement in astigmatism axis(P>0.05).CONCLUSION:In patients with mild KCN,objective dry retinoscopy overestimates the degree of myopia and astigmatism compared to subjective refraction.The irregular cornea in KCN likely impacts objective measurements.Subjective refraction allows compensation for irregularity,providing a more accurate correction.When determining refractive targets,the tendency of objective methods to overcorrect should be considered.
基金Supported by Shahid Beheshti University of Medical Sciences.
文摘AIM:To compare the subjective refraction data with autorefraction findings in high astigmatisms.METHODS:In a cross-sectional study,sampling was done from in different geographic regions in Iran using a multistage random cluster sampling method.All study participants underwent cycloplegic auto-refraction and subjective refraction using the red-green test.RESULTS:In this study,277 eyes of 158 students aged 8 to 15y were analyzed.According to the results,the mean difference between subjective refraction and autorefraction in measuring sphere,cylinder,spherical equivalent,J0,and J45 was-0.18±0.76,-0.36±0.40,-0.36±0.79,0.15±0.20,and 0.05±0.21 respectively.The correlation of these two refraction methods in measuring the aforementioned indices was 0.963,0.898,0.960,0.931,and 0.948 respectively.The 95%limits of agreement of the two methods in measuring the above indices were-1.66 to 1.31,-1.14 to 0.42,-1.91 to 1.19,-0.24 to 0.54,and-0.36 to 0.47 respectively.The agreement between the two methods decreased with increasing cylinder power,and the best agreement was found in myopic individuals.CONCLUSION:The measurements obtained by autorefractometer have a significantly higher cylinder average compared to subjective refraction.However,in the cylinder range of 4–5 diopters,the values of J0 and J45 do not have a high correlation.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2023YFB3811400 and 2022YFB3806000)the National Natural Science Foundation of China(Grant No.12074314)+1 种基金the Science and Technology New Star Program of Shaanxi Province,China(Grant No.2023KJXX-148)the Fundamental Research Funds for the Central Universities。
文摘The emergent metagrating,with its unique and flexible beam shaping capabilities,offers new paths to efficient modulation of acoustic waves.In this work,an acoustic metagrating is demonstrated for high-efficiency and wide-angle anomalous refraction.It is shown that the normal reflection and transmission can be totally suppressed by properly modulating the amplitude and phase characteristics of the metagrating supercells for high-efficiency anomalous refraction.The anomalous refraction behavior is achieved in the wide range of incident angles from 28°to 78°,and the efficiency of-1st order diffraction is higher than 90%by finely designing the metagrating structure.The anomalous refraction behaviors are verified experimentally at incidence angle of 28°,45°,and 78°,respectively.The demonstrated metagrating is anticipated to possess efficient wide-angle composite wavefront engineering applications in such fields as communications.
基金Supported by the Shenzhen Science and Technology Program (No.JCYJ20210324142800001).
文摘AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 emmetropia(E),429 low myopia(LM),80 moderate myopia(MM),and 32 low hypermetropia(LH)]aged 10 to 13y were analyzed.RPRs were measured using MRT without mydriasis.MRT results showed RPR at 0-15°(RPR 0-15),15°-30°(RPR 15-30),and 30°-45°(RPR 30-45)annular in the inferior(RPR-I),superior(RPR-S),nasal(RPR-N),and temporal(RPR-T)quadrants.Spherical equivalent(SE)was detected and calculated using an autorefractor.RESULTS:There were significant differences of RPR 15-30 between groups MM[0.02(-0.12;0.18)]and LH[-0.13(-0.36;0.12)](P<0.05),MM and E[-0.06(-0.20;0.10)](P<0.05),and LM[-0.02(-0.15;0.15)]and E(P<0.05).There were also significant differences of RPR 30-45 between groups MM[0.45(0.18;0.74)]and E[0.29(-0.09;0.67)](P<0.05),and LM[0.44(0.14;0.76)]and E(P<0.001).RPR values increased from the hyperopic to medium myopic group in each annular.There were significant differences of RPR-S between groups MM[-0.02(-0.60;0.30)]and E[-0.44(-0.89;-0.04)](P<0.001),and LM[-0.28(-0.71;0.12)]and E(P<0.05).There were also significant differences of RPR-T between groups MM[0.37(0.21;0.78)]and LH[0.14(-0.52;0.50)](P<0.05),LM[0.41(0.06;0.84)]and LH(P<0.05),and LM and E[0.29(-0.10;0.68),P<0.05].A Spearman’s correlation analysis showed a negative correlation between RPR and SE in the 15°-30°(P=0.005),30°-45°(P<0.05)annular(P=0.002),superior(P<0.001),and temporal(P=0.001)quadrants.CONCLUSION:Without pupil dilation,values for RPR 15-30,30-45,RPR-S,and T shows significant differences between myopic eyes and emmetropia,and the differences are negatively correlated with SE.
文摘AIM:To evaluate the refraction difference value(RDV)variations in children and adolescents with different refractive errors and analyze its correlation with refractive development.METHODS:Participants aged 4-16y with different refractive statuses(hyperopia,emmetropia,myopia)underwent comprehensive eye examinations,including spherical equivalent(SE)refraction,axial length(AL),total RDV(TRDV),and RDVs at various eccentricities(0°-15°,15°-30°,30°-45°)and quadrants(inferior,superior,nasal,temporal).Statistical analysis involved one-way ANOVA for group comparisons and Pearson correlation for examining relationships between SE/AL and RDVs.Paired t-tests compared quadrant-specific RDVs within groups.RESULTS:Significant difference was found in TRDV(P<0.001),RDV15°-30°(P=0.033),RDV30°-45°(P<0.001),RDV-inferior(RDV-I,P<0.001)and RDV-temporal(RDV-T,P<0.001)among hyperopia,emmetropia and myopia group.Pearson correlation analysis revealed a negative correlation of SE with TRDV(P=0.001),RDV30°-45°(P=0.004),RDV-I(P=0.047),and RDV-T(P<0.001).The differences between RDV-superior(RDV-S)and RDV-I were statistically significant in all groups(P<0.001 for all)and between RDV-T and RDV-nasal(RDV-N)were statistically significant in hyperopia group(P<0.001).Within the premyopic group,the analysis revealed a negative correlation of SE with RDV-I(P=0.009).Pearson correlation analysis revealed a positive correlation of AL with TRDV(P=0.036),RDV15°-30°(P=0.004),RDV30°-45°(P<0.001),RDV-S(P=0.003),RDV-I(P<0.001),RDV-T(P<0.001),RDV-N(P=0.022),while revealed a negative correlation of AL with RDV0-15°(P=0.018).CONCLUSION:Our study indicates TRDV,RDV30°-45°,RDV-I,RDV-T may relate to refractive development,and a negative correlation between SE and RDV-I in pre-myopic children.
基金supported by the National Key R&D Program of China(No.2021YFE0110900)the National Natural Science Foundation of China(Nos.U22B2078 and 11991033)。
文摘Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.
基金the National Natural Science Foundation of China (Nos.52304123 and 52104077)the Postdoctoral Fellowship Program of CPSF (No.GZB20230914)+1 种基金the China Postdoctoral Science Foundation (No.2023M730412)the National Key Research and Development Program for Young Scientists (No.2021YFC2900400)。
文摘Acoustic emission(AE)localization algorithms based on homogeneous media or single-velocity are less accurate when applied to the triaxial localization experiments.To the end,a robust triaxial localization method of AE source using refraction path is proposed.Firstly,the control equation of the refraction path is established according to the sensor coordinates and arrival times.Secondly,considering the influence of time-difference-of-arrival(TDOA)errors,the residual of the governing equation is calculated to estimate the equation weight.Thirdly,the refraction points in different directions are solved using Snell’s law and orthogonal constraints.Finally,the source coordinates are iteratively solved by weighted correction terms.The feasibility and accuracy of the proposed method are verified by pencil-lead breaking experiments.The simulation results show that the new method is almost unaffected by the refraction ratio,and always holds more stable and accurate positioning performance than the traditional method under different ratios and scales of TDOA outliers.
文摘The article develops coordinate-invariant methods to calculate reflection and refraction of plane monochromatic waves at the plane boundary between two isotropic and an isotropic and an anisotropic medium. The vectorial wave equation for the electric field is used to determine polarization vectors to known refraction vectors and this is applied to uniaxial media. Then it is shortly shown how the boundary conditions can be derived using the Heaviside step function and its derivatives which are the delta function and its derivatives. As preparation to the anisotropic case, there are calculated in coordinate-invariant way the amplitude relations for the reflection and refraction between two isotropic media and then in analogous way, the case of reflection and refraction between an isotropic and an anisotropic medium. This is then specialized for perpendicular incidence. It is shown that negative refraction such as discussed in last twenty-five years is impossible.
文摘Introduction: Refractive errors in school children continue to receive less attention and priority in many developing countries. Refractive errors can be a source of poor vision and disinterest in school. The aim of this study was to describe the epidemiological and clinical characteristics of ametropia in school children. Materials and Methods: This was a descriptive cross-sectional study carried out at the International Ophthalmology Center of Mali covering the period from January 1 to June 30, 2024, involving all school children. Results: A total of 207 children out of 702 school children received during the study period presented refractive errors. The most affected age group was 16 - 20 years old, with an average age of 16.95 years. The female sex was the majority, with 77.2% compared to 22.2% for the male sex. The main reasons for consultation were visual fatigue (36.2%) and tearing (20.2%). Hyperopia astigmatism was the most common refractive error, with a frequency of 62.3%. Low ametropia (Discussions: The management of refractive errors in school children is a major factor in their educational success. Conclusion: Early detection and management of refractive needs in school children can be key elements allowing them to be more efficient in daily activities.
文摘As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice.
文摘AIM:To analyze the two-year visual and refractive outcomes as well as the safety,and efficacy of photorefractive keratectomy(PRK)surgery for myopia.METHODS:In this prospective cohort study,63 eligible patients were recruited,including 45 women(71.4%)and 18 men(28.6%).Demographic characteristics along with pre-and post-operative clinical data including visual acuity,refraction,maximum ablation,spherical and cylindrical error,and residual stromal bed(RSB)were evaluated.RESULTS:The mean age of the patients was 35.42±8.16y(range 22 to 55y).The mean spherical and cylindrical error before surgery were-2.23±1.58 D(range-5 to+0.25)and-1.24±0.94 D,respectively(range-3.75 to 0.00).The mean efficacy and safety of PRK surgery at 2y follow-up were 0.98±0.06 and 1.01±0.04 respectively.The lower age was significantly correlated with a higher amount of efficacy index(P<0.001,r=-0.42).Also,the lower amount of preoperative myopia and spherical equivalent(SE)were correlated with a higher safety index(P<0.001,r=-0.44;P<0.001,r=-0.46).CONCLUSION:The two-year efficacy and safety of PRK for the treatment of low myopia is excellent.Younger age and lower amount of refractive error are correlated with higher efficacy and safety indices of the surgery.
基金supported by the National Natural Science Foundation of China(No.12174199)the Wanjing Horizontal Research and Development Fund for Nature(No.HJ1060319960015).
文摘Based on optofluidics and whispering gallery mode(WGM)theory,here an optofluidic refractive index sensor with microtube-coupled suspended core fiber(SCF)is proposed.It solves the issues of general sensors with microcavity-coupled fiber taper such as too fragile,unstable performance due to open coupling,poor portability and repeatability,while overcoming the poor performance of low refractive index sensing in general full-package fiber sensors.The sensor only needs a very small amount of liquid sample(about 1.8 nL).The proposed sensor combines the excellent performance of full package,optofluidics and WGM resonator.The resonant characteristics and sensing performance of the sensor are analyzed and discussed by the theoretical simulation.The simulation results indicate that the sensor has a wide refractive index sensing range(1.330-1.700)and good performance.The resonance wavelength shift has a good linear relationship with the liquid refractive index variation.In the low refractive index region,the sensitivity is 222.5-247.5 nm/RIU,Q-factor is 1.03×10^(3) and the detection limit is 3.64×10^(-4) RIU.In the medium and high refractive index regions,the sensitivity is 564.4-846.2 nm/RIU,Q-factor is up to 8.62×10^(4),and the detection limit can be as low as 1.29×10^(-6) RIU.The sensor exhibits a high sensitivity,a high Q-factor and a very low detection limit.
基金Supported by Natural Science Foundation of Sichuan Province(No.2022NSFSC0754)Project of Nanchong Science and Technology Bureau(No.22SXQT0350).
文摘AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 healthy 3-week-old rabbits were randomly assigned to one of the four groups with 8 in each group for 12wk:Control group(NC)under low blue light(output ratio of blue light 1.8%)at low illuminance(341 lx),HI group under low blue light(output ratio of blue light 1.6%)at high illuminance(5057 lx),simulating natural light(S-NL)group under high blue light(output ratio of blue light 4.9%)at high illuminance(5052 lx),and MB group under high blue light(output ratio of blue light 5.2%)at low illuminance(342 lx).The lighting in each group were provided by light emitting diode(LED)lamps emitting visible light(range 380-780 nm)in addition to(or not)LED lamps only emitting short wavelength(range 380-500 nm).Refraction,axial length,and corneal curvature radius were assessed by retinoscopy,ultrasonography and keratometry,respectively.Average data of both eyes for each animal were used as single values and compared among groups.RESULTS:During the 12-week intervention,all animals had an emmetropization period.The decrease of refraction in rabbits in HI group was similar to S-NL group,both slower than that of NC group(P<0.001).At the 12th week,the refraction(3.000±0.267 D)and vitreous cavity depth(7.421±0.168 mm)of S-NL was similar to HI group(3.250±0.267 D,7.264±0.256 mm),significantly different from NC group(1.937±0.291 D,7.825±0.313 mm;P<0.001 for both).High blue light at low illuminance had little effect on refraction change.At the end of intervention,the difference of refraction(2.219±0.281 D)and vitreous cavity depth(7.785±0.229 mm)in MB group were not statistically significant(P=0.311,P=0.749)compared with NC group.The other components were less affected by lighting conditions(P>0.05).CONCLUSION:The light levels per se but not the rich in spectral content of short wavelengths determine the inhibitory effect of ambient lighting on myopia development in rabbits.
基金supported by the Natural Science Foundation of Tianjin City (No.19JCYBJC17000)the National Natural Science Foundation of China (No.11905159)。
文摘A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.
文摘AIM:To compare refractive error and angle of deviation in patients with basic esotropia and basic exotropia.METHODS:A retrospective review was conducted on the medical records of patients with basic-type strabismus.Demographic data,refractive error,best-corrected distance visual acuity(BCVA),and the horizontal and vertical angle of deviation between basic esotropia and exotropia patients were compared.RESULTS:Among the 7129 patients(mean age 22.98±14.81y)evaluated,44.7%(3185 cases,54.9%male)exhibited basic-type esotropia,while 55.3%(3944 cases,53.9%male)presented with basic-type exotropia.Basic esotropia cases exhibited more hyperopic spherical equivalent measurements in both eyes(right:0.53±3.07 vs left:0.56±2.98 D)than those with basic exotropia(right eye:-0.33±2.84 vs left eye:-0.24±2.68 D,P<0.001 for both eyes).Patients with basic esotropia had significantly greater horizontal deviation angles(near:36.08±18.87 PD and far:35.56±18.75 PD)compared to those with basic exotropia(near:33.75±16.11 PD and far:33.26±15.90 PD,P<0.001).Conversely,patients with basic exotropia had slightly higher vertical deviation angles(near:1.67±5.80 PD and far:1.72±5.89 PD)compared to those with basic esotropia(near:1.12±4.57 PD and far:1.12±4.58 PD,P<0.001).Patients with basic esotropia underwent surgical intervention at younger ages compared to basic exotropia individuals(19.68±15.99 vs 25.66±13.20,P<0.001).CONCLUSION:Basic esotropia patients present more hyperopic refractive errors,better visual acuity,larger horizontal yet smaller vertical ocular misalignments,and tend to undergo strabismus surgery at younger ages relative to basic exotropia cases.
基金Supported by the National Natural Science Foundation of China(No.82171093).
文摘AIM:To analyze ocular parameters and refractive status in children aged 3-12y and to explore differences in these parameters across age groups with identical refractive status for studying refractive progression.METHODS:Demographic characteristics,cycloplegic refraction data,and ocular parameters of the participants were collected.Changes in ocular parameters were described according to different age groups.After adjusting for refractive factors,the relationship between age and ocular parameters was explored.Standard regression coefficients(β)obtained from multiple linear regressions were used to compare the magnitude of the effect of age on the parameters and ocular components on refractive power.RESULTS:Data were collected from the right eyes of 1504 participants.Lens thickness(LT)decreased with age,whereas the axial length(AL)and anterior chamber depth(ACD)increased.In the high-hyperopia group,changes in age were only associated with AL and LT.In the low-myopia group,the increase in age was also associated with corneal astigmatism.In the overall model,theβvalue for LT was the highest at 0.41,whereasβfor ACD and AL was significant in all groups except for the high-hyperopia group.Theβvalue of the LT on refractive power in children was slightly greater in the low age group than in the high age group.CONCLUSION:Among children with the same refractive status,the older the age,the longer the axis length and the thinner the lens.The lens affected refractive power in children in the younger age group more than in the older age group.The ocular parameter most affected by age was LT.
文摘AIM:To report the refractive and surgical outcomes of scleral buckling(SB)with or without pars plana vitrectomy(PPV)in patients with pseudophakic rhegmatogenous retinal detachment(PRRD).METHODS:A consecutive case series of patients with pseudophakia who underwent retinal detachment(RD)surgery was enrolled.The SB procedures were selected to initially treat primary pseudophakic PRRDs and SB-PPV for more complex cases,according to preoperative findings.Eyes with anterior chamber intraocular lens,proliferative vitreoretinopathy anterior to equator,previous invasive glaucoma surgery,severe degenerative myopia or macular hole,and<6mo follow-up were excluded from outcomes analysis.The primary clinical outcome measures were the single surgery anatomic success(SSAS)and final surgery anatomic success(FSAS)rates.Secondary outcome measures were postoperative visual acuity and refractive error.RESULTS:A total of 81 consecutive patients(81 eyes)were enrolled for analysis,comprising 66(81%)men and 15(19%)women with a mean age of 58y(range,33-86y)and the mean final follow-up period was 21.0±19.6mo.A total of 62 PRRDs(n=62;76.5%)were repaired with an initial SB,and 19 PRRDs(n=19;23.5%)were repaired with a combined SB-PPV.The SSAS and FSAS rates were 92.6%(75/81)and 100%(81/81),respectively.All initial failures had retinal reattachment after the secondary PPV.The mean final postoperative best-corrected visual acuity(BCVA)was 0.42±0.33 logMAR(visual acuity 20/55)and final mean refractive error was-1.48±1.40 diopters.The patients who underwent initially SB-PPV had a significantly longer duration of RD and a higher giant retinal tear rate(P<0.05)preoperatively.SSAS was 56/62(90.3%)and 19/19(100%),and the mean postoperative refractive error was-1.30±1.32 D and-1.53±1.38 D for the patients in the SB and SB-PPV groups,respectively.There was no statistically significant difference for those who had SSAS and postoperative refractive errors between the 2 groups.The postoperative BCVAs of the patients with SSAS were not significantly better in the SB group(median,20/40)than in the SB-PPV group(median 20/50).In the SB group,patients with macula-on had better visual acuity postoperatively than patients with macula-off(P=0.000).CONCLUSION:The initial surgical procedures of SB with or without PPV according to the preoperative findings achieve a high reattachment rate and an acceptable refractive error for primary pseudophakic RRD management.
文摘AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students using simple random sampling.Objective refraction,ocular alignment,vergence and accommodative performance were measured and assessed in all participants.Data on QOL were collected using the College of Optometrists in Vision Development-Quality of Life(COVD-QOL)Questionnaire.The effect of mentioned parameters on the QOL were evaluated.RESULTS:Totally 726 students with mean age of 21.35±1.88y were evaluated in this study,51.5%of whom were female.Esophoria was caused significantly lower QOL in the domains of somatic symptoms and occupationalphysical symptoms(P<0.05);Besides,esotropia decreased QOL in domains of somatic symptoms P=0.002 and psychological factors(P=0.023).Students with accommodation insufficiency experienced more symptoms in all domains(P<0.05)except for psychological factors(P=0.07).Increasing in the near point of convergence and accommodation and decreases QOL and increasing accommodative facility increases QOL(all P<0.05).Myopia and astigmatism cause decrease in QOL(both P<0.05),but hyperopic students had better QOL in comparison with others(P<0.05).CONCLUSION:Screening programs and treatment of refractive errors and binocular vision anomalies,especially phoria and accommodative insufficiency,positively impact the QOL and academic achievements of university students.
基金Supported by Key Research and Development Program of Shaanxi Province(No.2024SF-YBXM-320)the Clinical Research Project of the Fourth Military Medical University(No.2022LC2247)Medical Staff Training Boosting Project of Xijing Hospital,Air Force Medical University(No.XJZT24CY52).
文摘AIM:To compare the changes in preschool refractive status,ocular biological parameters,and higher-order aberrations in children with retinopathy of prematurity(ROP)after retinal laser photocoagulation or anti-vascular endothelial growth factor(anti-VEGF)treatment and explore their underlying factors.METHODS:This observational study involved 118 eyes of 59 children,aged 3 to 6y,with ROP followed up between March 2023 and October 2024.They were divided into the laser,anti-VEGF,and anti-VEGF+laser groups.The laser group received a single session of laser photocoagulation.The anti-VEGF group received a single anti-VEGF treatment.The anti-VEGF+laser group received a single anti-VEGF treatment after birth followed by supplementary laser treatment within 2wk to 6mo.Ocular biological parameters were measured using IOL Master 700 and Pentacam HR.Right-eye higher-order aberrations were measured using the OPD-Scan III.Best-corrected visual acuities(BCVA),refractive statuses,ocular biological parameters,and higherorder aberrations were assessed and compared.Multiple linear regression analysis was conducted to evaluate the relationships among ocular biological parameters,higherorder aberrations,spherical equivalent(SE),and treatment methods.Pearson’s correlation coefficients were used to assess the relationships between the SE and higher-order aberrations.RESULTS:The laser group had a higher incidence of myopia and a lower SE than the anti-VEGF group.The incidence of astigmatism and cylindrical power were significantly lower for the anti-VEGF than for the laser and anti-VEGF+laser groups(P<0.05).The anterior corneal surface astigmatism was higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The anterior corneal surface K2 and lens thickness were higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The whole-eye higher-order aberration root mean square(RMS)values for the right eye were significantly higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group.The whole-eye trefoil RMS values for the right eye were also significantly higher for the laser and anti-VEGF+laser groups than for the anti-VEGF group(P<0.05).Laser treatment was significantly associated with SE,anterior corneal surface curvature and astigmatism,lens thickness,whole-eye highorder aberrations,and whole-eye trefoil(all P<0.05).CONCLUSION:Children with ROP who received laser treatment have higher myopia and astigmatism than those who received anti-VEGF treatment.Children treated with laser or supplementary laser treatment have higher anterior corneal astigmatism,anterior corneal curvature,thicker lenses,whole-eye higher-order aberrations,and whole-eye trefoil.The cause of myopia in children with ROP after laser treatment is increased anterior corneal surface curvature and lens thickness.
基金Supported by the Zhejiang Traditional Chinese Medicine Science and Technology Plan(No.2023ZL241)Zhejiang Medical Science and Technology Plan(No.2025KY648).
文摘AIM:To evaluate the effect of different monochromatic lights on the refractive status and the secretion levels of neurotransmitters in the progressive myopic model of guinea pigs.METHODS:Guinea pigs(n=90)underwent different monochromatic lights irradiation for two weeks were randomly divided into 6 groups:white light(control),ultraviolet(UV),blue,green,red,and simulative sunlight(simSUN).The refractive status and axial length(AL)were measured.Transmission electron microscopy,Masson’s trichrome staining and hematoxylin-eosin staining were performed to observe the structural changes of retina and sclera.High-performance liquid chromatography(HPLC),western blotting and immunofluorescence were used to measure neurotransmitters and their receptors.RESULTS:Myopia models were established successfully.When compared the degrees of change in myopic eyes of control group,the UV group showed a minor decrease in AL and refraction,along with a significant increase in scleral thickness.In contrast,the red and green groups revealed a net increase in AL and refraction,coupled with a net decrease in scleral thickness(all,P<0.01).The dopamine concentration increased in the UV group,while concentrations of serotonin and melatonin significantly decreased(all,P<0.01).The groups that were exposed to UV,blue and simSUN,the expression of dopamine receptor D2(DRD2)increased,and the expression of hydroxytryptamine receptor 2A(HTR2A)and melatonin receptor type 2(MT2)decreased significantly when compared to the control group(all P<0.01).CONCLUSION:Exposure to short-wavelength light could slow the development of myopia by promoting the production of dopamine and suppressing the serotonin and melatonin concentration.The neurotransmitter receptors MT2,DRD2,and HTR2A in the sclera appear to play different roles by different color lights in myopic guinea pigs.
