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 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
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 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
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 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 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
Polymer optical materials are becoming increasingly important in modern technologies owing to their unique properties.This study applies coupled perturbed density functional theory(DFT)to predict the refractive index(...Polymer optical materials are becoming increasingly important in modern technologies owing to their unique properties.This study applies coupled perturbed density functional theory(DFT)to predict the refractive index(RI)and Abbe number of polymers.Using the LorentzLorenz equation,the frequency-dependent polarizability and molecular volume were calculated to estimate RI.Wavelength-dependent RI values were used to derive the Abbe numbers.Our results show a strong correlation with experimental data,with Pearson coefficients of 0.912 for RI and 0.968 for Abbe number,enabling the introduction of linear correction functions to minimize discrepancies between theoretical predictions and experimental results.By categorizing polymers into classes such as poly(methyl methacrylate)(PMMA)-,polyethylene(PE)-,polycarbonate(PC)-,polyimide(PI)-,and polyurethane(PU)-based materials,this method enables precise predictions and reduces discrepancies using linear correction functions.This efficient and direct computational framework avoids the complexity of traditional models and offers a practical tool for the design and optimization of advanced optical materials.展开更多
Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic syst...Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic system.Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated.In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls,and the geometric difference between the dielectric columns of the sublattices.Straight photonic crystal waveguides with three types of domain walls(bearded,zigzag,armchair)are constructed.Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands.Our findings might have significant implications in the field of novel optical devices.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 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 propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:Y...AIM:To propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:YAG laser posterior capsulotomy for each subtype.METHODS:A retrospective analysis was performed on 5 eyes from 5 patients with late postoperative CBS.Patients were categorized into turbid(3 eyes)or clear(2 eyes)types based on the turbidity of intracapsular fluid.Uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),refractive status,slit-lamp images,Pentacam Scheimpflug data,and ultrasound biomicroscopy(UBM)images were evaluated before and 1mo after successful Nd:YAG laser posterior capsulotomy.RESULTS:Nd:YAG laser posterior capsulotomy significantly improved UCVA and BCVA in all 5 late CBS eyes.Pentacam imaging:turbid intracapsular fluid showed hyperreflection between posterior capsule and intraocular lens(IOL);clear fluid showed hyporeflection.UBM:posterior capsule was clear in turbid type but poorly defined in clear type.Capsulotomy increased aqueous depth only in clear type.Refractive changes:turbid fluid induced myopic shift.Clear type myopic shift was due to anterior IOL displacement and clear fluid-induced concave lens effect.CONCLUSION:Nd:YAG laser posterior capsulotomy is effective for late CBS.Turbid and clear late CBS types differ in imaging(Pentacam/UBM)and refractive mechanisms,supporting the proposed classification’s clinical value.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
This study explores the molecular design of sulfur-containing polymers with high refractive indices(RI)and optimized Abbe numbers for advanced optical applications.The high molar refraction and low dispersion of sulfu...This study explores the molecular design of sulfur-containing polymers with high refractive indices(RI)and optimized Abbe numbers for advanced optical applications.The high molar refraction and low dispersion of sulfur make it an ideal component for enhancing the optical properties of polymers.Density functional theory(DFT)calculations were employed to predict the RI and Abbe numbers for a range of sulfurbased polymers.To improve the accuracy of the theoretical predictions,a correction function was developed by comparing the calculated values with experimental data.The key polymer families investigated included sulfur-containing polycarbonates,heterocyclic optical resins,and cycloolefins,all modified to balance RI enhancement with dispersion control.The results demonstrate that increasing the sulfur content and introducing specific heterocycles and bridged rings can effectively increase the RI while maintaining desirable Abbe numbers.Polymers incorporating 1,4-dithiane and sulfur-bridged rings exhibit excellent optical clarity and minimal visible light absorption,making them suitable for lens and coating applications.The study also calculated the UV-visible spectra for the most promising polymers,confirming their high transparency.This work establishes a predictive framework for developing high-performance optical polymers and offers a systematic approach for balancing the refractive index and dispersion,thereby providing valuable insights for the design of next-generation optical materials.展开更多
Background and Objective:Refractive surgery has evolved significantly,with artificial intelligence(AI)offering new possibilities for enhancing patient selection,surgical planning,and postoperative outcome prediction.W...Background and Objective:Refractive surgery has evolved significantly,with artificial intelligence(AI)offering new possibilities for enhancing patient selection,surgical planning,and postoperative outcome prediction.While AI has demonstrated promising applications,its integration into clinical practice remains inconsistent due to challenges in data standardization,model interpretability,and regulatory concerns.This review examines the current applications,limitations,and future directions of AI in refractive surgery,with a focus on its role in laser vision correction(LVC)and phakic intraocular lens(IOL)implantation.Methods:A literature review was conducted using peer-reviewed studies published between January 2010 and October 2024,sourced from databases including Google Scholar,PubMed,Embase,and Web of Science.Studies were selected based on predefined inclusion criteria,covering AI applications in refractive surgery.A total of 33 key studies(16 on LVC and 17 on phakic IOLs)were analyzed,focusing on machine learning and deep learning techniques used for patient selection,surgical optimization,and complication prediction.Only English-language studies were included.Key Content and Findings:AI models utilizing structured tabular data,imaging,and multimodal inputs have demonstrated superior performance in predicting surgical outcomes and refining patient selection compared to traditional methods.Machine learning approaches such as random forests,extreme gradient boosting,and ensemble techniques,alongside deep learning architectures like convolutional neural networks and generative models,have improved risk assessment and surgical planning.In LVC,AI enhances ectasia risk assessment,keratoconus detection,and myopic regression prediction.In phakic IOL implantation,AI improves postoperative vault prediction,lens sizing,and refractive error estimation.Multimodal AI systems integrating imaging,textual data,and clinical parameters hold promise for more comprehensive patient evaluations.However,challenges such as data heterogeneity,limited external validation,and regulatory barriers hinder widespread clinical adoption.Conclusions:AI is transforming refractive surgery by enhancing precision,personalization,and patient safety.Its integration into clinical workflows has the potential to improve surgical outcomes and patient satisfaction.Future efforts should focus on advancing multimodal AI,improving model generalizability,and addressing ethical and regulatory challenges to fully harness AI’s potential in refractive surgery.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
Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of pr...Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield rate.Nevertheless,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index modulation.Herein,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer composites.The high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.展开更多
AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was...AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was cross-sectional.Totally 3343 participants were included in the study.The initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D lens.The inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVA<0.6 decimal(0.20 logMAR)and/or a VA with+2.00 D≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to 14y.Among the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye examination.The estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total sample.While around 0.18%of the total sample had hyperopia value exceeding+1.75 D.Refractive astigmatism(cil<-0.75 D)was found in 0.21%(7/3343)of the children.The VI prevalence was 1.26%of the total sample.Among our cases of VI,76.2%could be attributed to uncorrected refractive error.Amblyopia was detected in 0.66%(22/3343)of the screened children.There was no statistically significant correlation observed between age or gender and refractive values.CONCLUSION:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error observed.These findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI.展开更多
A temperature and refractive index sensor based on fiber Bragg grating(FBG)end surface cascade open Fabry-Pérot(FP)cavity has been designed and demonstrated experimentally.The open FP cavity has been fabricated o...A temperature and refractive index sensor based on fiber Bragg grating(FBG)end surface cascade open Fabry-Pérot(FP)cavity has been designed and demonstrated experimentally.The open FP cavity has been fabricated on the end face of an FBG by dislocation fusion in this work,the open FP cavity could be used for refractive index sensing,and the temperature is measured by the FBG.The working principle of the sensor and the method of improving the sensitivity are analyzed by theoretical simulation.The refractive index sensitivity of the sensor is 1108.4 nm/RIU,while the maximum fluctuation of the sensor stability experiment detection is 0.005 nm.The results show that it has satisfactory characteristics.The sensor is a compact all-fiber structure,so it has potential applications in the field of temperature refractive index sensing,such as biomedical and capacitor electrolyte detection.展开更多
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.
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 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.
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.
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 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.
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.
基金financially supported by the Shenzhen Science and Technology Project(Nos.JCYJ20210324095210028,JSGGZD20220822095201003)the National Natural Science Foundation of China(U21A2087)。
文摘Polymer optical materials are becoming increasingly important in modern technologies owing to their unique properties.This study applies coupled perturbed density functional theory(DFT)to predict the refractive index(RI)and Abbe number of polymers.Using the LorentzLorenz equation,the frequency-dependent polarizability and molecular volume were calculated to estimate RI.Wavelength-dependent RI values were used to derive the Abbe numbers.Our results show a strong correlation with experimental data,with Pearson coefficients of 0.912 for RI and 0.968 for Abbe number,enabling the introduction of linear correction functions to minimize discrepancies between theoretical predictions and experimental results.By categorizing polymers into classes such as poly(methyl methacrylate)(PMMA)-,polyethylene(PE)-,polycarbonate(PC)-,polyimide(PI)-,and polyurethane(PU)-based materials,this method enables precise predictions and reduces discrepancies using linear correction functions.This efficient and direct computational framework avoids the complexity of traditional models and offers a practical tool for the design and optimization of advanced optical materials.
基金supported by the Self-Deployment Project Research Program of the Haixi Institutes,Chinese Academy of Sciences(No.CXZX-2022-GH09)the National Natural Science Foundation of China(No.11774103)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR114)。
文摘Realizing the valley Hall effect by breaking the spatial inversion symmetry of photonic systems has become a cutting-edge field of micro-nano-optics,since the valley degree of freedom was introduced into photonic system.Various novel devices based on the domain walls of the valley photonic crystals have also been demonstrated.In this article,we investigate the variation of edge states by the modulation of refractive index within the domain walls,and the geometric difference between the dielectric columns of the sublattices.Straight photonic crystal waveguides with three types of domain walls(bearded,zigzag,armchair)are constructed.Simulation results show that the creation of a double-edge state in the band diagram results in two windows of stable transmission in tunable bands.Our findings might have significant implications in the field of novel optical devices.
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 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 Research and Development Program of Shaanxi Province(No.2021SF-161)the Medical Research Project of Xi’an Science and Technology Action Plan[No.2019114613YX001SF041(1)]。
文摘AIM:To propose a novel classification system for late postoperative capsular block syndrome(CBS)based on the turbidity of intracapsular fluid,and to investigate the imaging and refractive changes before and after Nd:YAG laser posterior capsulotomy for each subtype.METHODS:A retrospective analysis was performed on 5 eyes from 5 patients with late postoperative CBS.Patients were categorized into turbid(3 eyes)or clear(2 eyes)types based on the turbidity of intracapsular fluid.Uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),refractive status,slit-lamp images,Pentacam Scheimpflug data,and ultrasound biomicroscopy(UBM)images were evaluated before and 1mo after successful Nd:YAG laser posterior capsulotomy.RESULTS:Nd:YAG laser posterior capsulotomy significantly improved UCVA and BCVA in all 5 late CBS eyes.Pentacam imaging:turbid intracapsular fluid showed hyperreflection between posterior capsule and intraocular lens(IOL);clear fluid showed hyporeflection.UBM:posterior capsule was clear in turbid type but poorly defined in clear type.Capsulotomy increased aqueous depth only in clear type.Refractive changes:turbid fluid induced myopic shift.Clear type myopic shift was due to anterior IOL displacement and clear fluid-induced concave lens effect.CONCLUSION:Nd:YAG laser posterior capsulotomy is effective for late CBS.Turbid and clear late CBS types differ in imaging(Pentacam/UBM)and refractive mechanisms,supporting the proposed classification’s clinical value.
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.
基金supported by the Project of Shenzhen Science and Technology(Nos.JCYJ20210324095210028 and JSGGZD20220822095201003)the Shenzhen University 2035Program for Excellent Research(No.000003011002)the National Natural Science Foundation of China(No.U21A2087)。
文摘This study explores the molecular design of sulfur-containing polymers with high refractive indices(RI)and optimized Abbe numbers for advanced optical applications.The high molar refraction and low dispersion of sulfur make it an ideal component for enhancing the optical properties of polymers.Density functional theory(DFT)calculations were employed to predict the RI and Abbe numbers for a range of sulfurbased polymers.To improve the accuracy of the theoretical predictions,a correction function was developed by comparing the calculated values with experimental data.The key polymer families investigated included sulfur-containing polycarbonates,heterocyclic optical resins,and cycloolefins,all modified to balance RI enhancement with dispersion control.The results demonstrate that increasing the sulfur content and introducing specific heterocycles and bridged rings can effectively increase the RI while maintaining desirable Abbe numbers.Polymers incorporating 1,4-dithiane and sulfur-bridged rings exhibit excellent optical clarity and minimal visible light absorption,making them suitable for lens and coating applications.The study also calculated the UV-visible spectra for the most promising polymers,confirming their high transparency.This work establishes a predictive framework for developing high-performance optical polymers and offers a systematic approach for balancing the refractive index and dispersion,thereby providing valuable insights for the design of next-generation optical materials.
文摘Background and Objective:Refractive surgery has evolved significantly,with artificial intelligence(AI)offering new possibilities for enhancing patient selection,surgical planning,and postoperative outcome prediction.While AI has demonstrated promising applications,its integration into clinical practice remains inconsistent due to challenges in data standardization,model interpretability,and regulatory concerns.This review examines the current applications,limitations,and future directions of AI in refractive surgery,with a focus on its role in laser vision correction(LVC)and phakic intraocular lens(IOL)implantation.Methods:A literature review was conducted using peer-reviewed studies published between January 2010 and October 2024,sourced from databases including Google Scholar,PubMed,Embase,and Web of Science.Studies were selected based on predefined inclusion criteria,covering AI applications in refractive surgery.A total of 33 key studies(16 on LVC and 17 on phakic IOLs)were analyzed,focusing on machine learning and deep learning techniques used for patient selection,surgical optimization,and complication prediction.Only English-language studies were included.Key Content and Findings:AI models utilizing structured tabular data,imaging,and multimodal inputs have demonstrated superior performance in predicting surgical outcomes and refining patient selection compared to traditional methods.Machine learning approaches such as random forests,extreme gradient boosting,and ensemble techniques,alongside deep learning architectures like convolutional neural networks and generative models,have improved risk assessment and surgical planning.In LVC,AI enhances ectasia risk assessment,keratoconus detection,and myopic regression prediction.In phakic IOL implantation,AI improves postoperative vault prediction,lens sizing,and refractive error estimation.Multimodal AI systems integrating imaging,textual data,and clinical parameters hold promise for more comprehensive patient evaluations.However,challenges such as data heterogeneity,limited external validation,and regulatory barriers hinder widespread clinical adoption.Conclusions:AI is transforming refractive surgery by enhancing precision,personalization,and patient safety.Its integration into clinical workflows has the potential to improve surgical outcomes and patient satisfaction.Future efforts should focus on advancing multimodal AI,improving model generalizability,and addressing ethical and regulatory challenges to fully harness AI’s potential in refractive surgery.
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.
基金financially supported by the National Natural Science Foundation of China(Nos.52122316,52073108 and 52233005)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)。
文摘Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield rate.Nevertheless,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index modulation.Herein,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer composites.The high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.
文摘AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was cross-sectional.Totally 3343 participants were included in the study.The initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D lens.The inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVA<0.6 decimal(0.20 logMAR)and/or a VA with+2.00 D≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to 14y.Among the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye examination.The estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total sample.While around 0.18%of the total sample had hyperopia value exceeding+1.75 D.Refractive astigmatism(cil<-0.75 D)was found in 0.21%(7/3343)of the children.The VI prevalence was 1.26%of the total sample.Among our cases of VI,76.2%could be attributed to uncorrected refractive error.Amblyopia was detected in 0.66%(22/3343)of the screened children.There was no statistically significant correlation observed between age or gender and refractive values.CONCLUSION:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error observed.These findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI.
基金supported in part by the National Natural Science Foundation of China (Nos.61735014 and 61927812)the Shaanxi Provincial Education Department (No.18JS093)+2 种基金the Natural Science Basic Research Program of Shaanxi Province (No.2024JC-YBMS_530)the Operation Fund of Logging Key Laboratory of Group Company (No.2021DQ0107-11)the Graduate Student Innovation Fund of Xi’an Shiyou University (Nos.YCS23213178 and YCS22213185)。
文摘A temperature and refractive index sensor based on fiber Bragg grating(FBG)end surface cascade open Fabry-Pérot(FP)cavity has been designed and demonstrated experimentally.The open FP cavity has been fabricated on the end face of an FBG by dislocation fusion in this work,the open FP cavity could be used for refractive index sensing,and the temperature is measured by the FBG.The working principle of the sensor and the method of improving the sensitivity are analyzed by theoretical simulation.The refractive index sensitivity of the sensor is 1108.4 nm/RIU,while the maximum fluctuation of the sensor stability experiment detection is 0.005 nm.The results show that it has satisfactory characteristics.The sensor is a compact all-fiber structure,so it has potential applications in the field of temperature refractive index sensing,such as biomedical and capacitor electrolyte detection.
