The linear transmission impairments,such as the timing offset(TO),frequency offset(FO),and chromatic dispersion(CD),are major factors of signal degradations in coherent optical fiber communication systems.The estimati...The linear transmission impairments,such as the timing offset(TO),frequency offset(FO),and chromatic dispersion(CD),are major factors of signal degradations in coherent optical fiber communication systems.The estimation and compensation of such impairments play significant roles in the receiver side digital signal processing(DSP)unit.In this paper,we propose to combat the linear impairments systematically(including TO,FO and CD)with a joint timefrequency signal processing by taking the advantage of fractional Fourier transform(FrFT).In view of geometrical analysis,TO/FO induces a shift in time/frequency coordinate and the CD leads to the rotation in the fractional domain.Both mathematical derivations and geometrical interpretations have been established to unveil the relationships between impairments and linear frequency modulated(LFM)training symbols(TSs).By considering a typical coherent optical orthogonal frequency-division multiplexing(COOFDM)transmission system,three kinds of linear impairments have been jointly estimated by simple geometric calculations using appropriately designed TS based on FrFTs.Simulation and experimental results confirmed the feasibility of time-frequency techniques with better accuracy,less complexity,and improved spectral efficiency.展开更多
AIM:To analyze the effect of conbercept treatment on different types of macular edema secondary to retinal vein occlusion(RVO-ME)using optical coherence tomography(OCT)images.METHODS:This retrospective study included ...AIM:To analyze the effect of conbercept treatment on different types of macular edema secondary to retinal vein occlusion(RVO-ME)using optical coherence tomography(OCT)images.METHODS:This retrospective study included patients who first received conbercept injections for RVO-ME at Yijishan Hospital of Wannan Medical College from December 1,2017,to March 31,2022.Data on disease duration,age,hypertension,OCT images,central macular thickness(CMT),and best-corrected visual acuity(BCVA)were collected before and at 4-6 wk after treatment.Patients were divided into 4 groups according to different types of macular edema:cystoid macular edema(CME),sponge-like diffuse retinal thickening(SDRT),serous retinal detachment(SRD),and mixed type(FULL).Changes in CMT and visual acuity before and after treatment were compared among the groups to analyze differences in the effect of conbercept treatment on different ME types,and the effect of baseline CMT and visual acuity on post-treatment visual acuity.RESULTS:Totally 139 patients(139 eyes)were classified as having macular edema,including 62 males(44.6%)and 77 females(55.4%),with a mean age of 58.9±10.9 years,and they were divided into 4 groups based on different types of macular edema,including 54 cases(54 eyes)(mean age 59.6±11.1 years)in the CME group,23 cases(23 eyes;mean age 56.6±10.2 years)in the SDRT group,22 cases(22 eyes;mean age 57.8±12.0 years)in the SDR group,and 40 cases(40 eyes;mean age 60.0±10.7 years)in the FULL group.There were no significant differences in the duration of disease or age between groups(P>0.05).There was a significant difference in preoperative CMT between groups(P=0.01,one-way ANOVA),with the CMT in the FULL group being significantly greater than that in the SDRT group(P=0.03).There were no significant differences in pre-treatment visual acuity between the four groups(P=0.26).After conbercept treatment,the macular central recess thickness was reduced and visual acuity was improved in all four groups,among which the CMT in the CME and FULL groups was reduced significantly compared with the other two groups(P<0.05),and the visual acuity in the CME and SRD groups was improved significantly compared with the other two groups(P<0.05).Postoperative visual acuity was negatively correlated with preoperative CMT(P=0.044)and positively correlated with preoperative visual acuity(P<0.01).CONCLUSION:The efficacy of intravitreal conbercept in the treatment of RVO and macular edema may be related to the type of edema observed on OCT images,in which the efficacy is best in patients with CME but poor in patients with SDRT.展开更多
Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deteri...Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.展开更多
Accurate and early evaluation of dental physiological characteristics is essential for effective disease detection and management.Polarization-sensitive optical coherence tomography(PS-OCT)is a noninvasive high-resolu...Accurate and early evaluation of dental physiological characteristics is essential for effective disease detection and management.Polarization-sensitive optical coherence tomography(PS-OCT)is a noninvasive high-resolution imaging technique that can obtain tooth structure and physiological features through intensity,retardation and degree of polarization uniformity(DOPU)images.In this study,we use the information provided by the PS-OCT system,especially the retardation information,to assess the physiological characteristics of teeth.In addition,we introduce a novel parameter—the rate of change of the retardation value(R)—to evaluate the magnitude of birefringence of enamel,which serves as an indicator of enamel health and mineralization.The results demonstrate that PS-OCT not only provides structural detail comparable to microcomputed tomography(microCT),but also yields additional physiological characteristics insights through polarization-based contrast.These findings highlight the strong potential of PS-OCT for early diagnosis,functional evaluation and personalized monitoring in dental care.展开更多
AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopi...AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopic children.METHODS:AL,steep keratometry(K),flat K,posterior corneal keratometry(PK),total keratometry(TK),anterior chamber depth(ACD),horizontal corneal diameter(CD),and central corneal thickness(CCT)were obtained using IOL Master 700 and Pentacam AXL.The agreement between the devices was evaluated using intraclass correlation coefficients(ICC),Bland-Altman plots,and astigmatism vector analysis.RESULTS:Totally 175 myopic children(48.5%male)with a mean age of 10.29±2.14y were enrolled.The ICC and Bland-Altman plots indicated a satisfactory agreement for AL,ACD,and CCT.The mean difference in CD of-0.31±0.30 mm was considered clinically significant(>0.2 mm).Additionally,measurements of K and TK obtained from the IOL Master 700 showed good agreement.Nevertheless,there were clinically significant differences observed in PK,simulated keratometry(simK),total cornea power,and astigmatism(at least 10%of the cases with a difference of>10 degrees in meridian)between the two devices.CONCLUSION:The study findings demonstrate a significant difference in K,PK,astigmatism,and CD,indicating that the two optical biometers cannot be considered interchangeable.Therefore,it is recommended to utilize one kind device for follow-up examinations in myopic children.展开更多
AIM:To assess the current research status and emerging trends of the choriocapillaris(CC)by bibliometric analysis.METHODS:Publications spanning from January 2013 to May 2023 were retrieved on June 27th,2023,using the ...AIM:To assess the current research status and emerging trends of the choriocapillaris(CC)by bibliometric analysis.METHODS:Publications spanning from January 2013 to May 2023 were retrieved on June 27th,2023,using the Web of Science Core Collection.Bibliometric and visualized analyses were performed employing the bibliometrix,CiteSpace and VOSviewer.RESULTS:A total of 1563 papers met the inclusion criteria,and a publication growth trend was observed.The United States was the leading country in the CC field.Retina and Investigative Ophthalmology&Visual Science stood out as highly impactful and prolific journals.Research topics in the CC field encompassed choroidal neovascularization,choroidal thickness,central serous chorioretinopathy,agerelated macular degeneration,myopia,choroidal vascularity index,and diabetic retinopathy,based on the co-citation analysis.The keyword“high myopia”experienced a burst lasting until 2023.CONCLUSION:In the past decade,research in the field of CC has flourished due to recent advancements in choroidal imaging;with focus shifting towards elucidating its role in various diseases.This will provide novel insights into managing chorioretinal diseases and vision-preserving interventions.展开更多
Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effect...Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making.展开更多
AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patie...AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patients diagnosed with MS and a control group of 43 healthy hospital staff matched in terms of age and sex at Iran University,department of neurology and ophthalmology from March 2020 to March 2021.The ophthalmic parameters of each patient were recorded,and optical coherence tomography was used to evaluate the retinal thickness in the layers.RESULTS:This study enrolled a total of 85 participants,with a mean age of 40.44±11.52 years,including 61 females(72%).The control group consisted of 43 individuals with a mean age of 39.49±11.07 years,while the MS group comprised 42 participants with a mean age of 41.40±12.01 years.The mean disease duration in the MS group was 8.45±6.04 a.The thickness of the ganglion cell layer in the right eye was significantly lower in the MS group compared to the control group(P=0.034).In addition,except for the left nasal sector(P=0.106),the mean peripapillary neurofibrillation in all examined sectors were significantly lower in the MS group than in the control group(P<0.05).The average vessel density in both the deep and superficial capillary plexuses across all regions of both eyes was lower in the MS group than in the control group,with all comparisons for the superficial capillary plexus showing statistical significance(P<0.05 for all except the left nasal sector).CONCLUSION:The thickness of the retina of patients with MS is significantly reduced.Therefore,optical coherence tomography results can be used as a reliable tool to evaluate disease progression and prognosis in MS patients.展开更多
AIM:To investigate the association between anti-DFS70 antibody positivity and ocular parameters,specifically,the choroidal vascularity index(CVI)and other optical coherence tomography(OCT)metrics,in a healthy populati...AIM:To investigate the association between anti-DFS70 antibody positivity and ocular parameters,specifically,the choroidal vascularity index(CVI)and other optical coherence tomography(OCT)metrics,in a healthy population.METHODS:This age-and sex-matched case-control study enrolled 84 healthy individuals with positive anti-DFS70 antibody findings and 84 healthy negative controls.All participants underwent detailed ophthalmological examinations,including biometry and OCT imaging.Anti-DFS70 positivity was determined by indirect immunofluorescence and scored semi-quantitatively(1+to 3+).CVI was calculated from OCT images using a standardized protocol with Image J software.Statistical analyses,including Student’s t-test,Mann-Whitney U test,Spearman correlation,and logistic regression,were used to compare groups and identify predictive factors.RESULTS:The individuals who tested positive and negative for anti-DFS70 included in the study were matched for age(median age=47y)and sex(F:M=7:1).CVI was significantly lower in the anti-DFS70-positive group compared to the negative group.A higher anti-DFS70 antibody titer was significantly associated with decreased subfoveal and nasal choroidal thickness(P=0.016 and P=0.014,respectively).In univariate regression analysis,CVI was the only significant predictor of anti-DFS70 positivity[odds ratio(OR)=0.02,P=0.025].Multivariate analysis revealed a positive correlation between macular thinning outside the subfoveal area and anti-DFS70 status(P<0.05).CONCLUSION:Our study demonstrates a novel association between anti-DFS70 antibody positivity and reduced choroidal vascularity in healthy individuals.These findings suggest that anti-DFS70 antibodies may be associated with subtle choroidal vascular changes detectable by OCT,even in asymptomatic individuals.Further longitudinal research is warranted to clarify the underlying mechanisms and long-term clinical significance of these ocular changes.展开更多
AIM:To evaluate the therapeutic effects of ranibizumab on optic disc and macular microvascular perfusion in central retinal vein occlusion(CRVO)with macular edema(ME).METHODS:Optical coherence tomography angiology(OCT...AIM:To evaluate the therapeutic effects of ranibizumab on optic disc and macular microvascular perfusion in central retinal vein occlusion(CRVO)with macular edema(ME).METHODS:Optical coherence tomography angiology(OCTA)parameters,including optic disc vessel density(VD;including whole-disc VD,intra-disc VD,and peripapillary VD),superficial/deep capillary plexus(SCP/DCP)VD,and central macular thickness(CMT)were analyzed.Additional assessments included best-corrected visual acuity(BCVA)via Early Treatment Diabetic Retinopathy Study(ETDRS)chart and hemorheological profiling.CRVO patients received monthly intravitreal ranibizumab injections for three consecutive months.Pre-and post-treatment parameters were statistically compared.RESULTS:The study comprised 60 CRVO-ME patients(28 males;32 females),aged 50-78y(mean 63.3±7.6y)and 60 age-/sex-matched healthy controls.As compared with participants exhibiting normal funduscopic findings,CRVO patients demonstrated significantly elevated levels of low-shear-rate whole blood viscosity(LSR-WBV),high-shearrate whole blood viscosity(HSR-WBV),and aggregation index(AI,all P<0.05).In CRVO-affected eyes,vertical cupto-disc(C/D)ratio and optic cup volume were significantly smaller,whereas retinal nerve fiber layer(RNFL)thickness was significantly greater,compared to both unaffected contralateral eyes and normal control eyes(all P<0.05).Following treatment,VD of the entire optic disc(P<0.05),intra-disc VD(P<0.05),and peripapillary VD(P<0.05)all increased significantly relative to baseline.CMT decreased significantly(P<0.05),whereas macular SCP-VD and macular DCP-VD showed non-significant slight reductions(P>0.05).At baseline,BCVA of CRVO eyes correlated with whole-disc VD(r=-0.276,P=0.033),intra-disc VD(r=-0.342,P=0.009),and peripapillary VD(r=-0.335,P=0.007),with intra-disc VD demonstrating the strongest association.Besides,BCVA improvement,after the treatment,correlated positively with whole-disc VD(r=0.342,P=0.008)and intradisc VD(r=0.396,P=0.002).CONCLUSION:Optic disc blood perfusion is more closely associated with visual acuity than macular perfusion,suggesting intra-disc VD may serve as a potential biomarker for monitoring visual acuity changes in CRVO.Multiple ranibizumab injections significantly improve optic disc perfusion but may have exerted detrimental effects on the macula.CRVO patients shows higher hemorheological parameters than those with normal fundi.Reduced vertical C/D ratio and optic cup volume may be linked to CRVO incidence,potentially acting as susceptibility factors.展开更多
AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This o...AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This observational clinical study utilized a cross-sectional and prospective design,focusing on chronic alcohol consumers alongside a non-consuming control group.OCT/OCTA imaging parameters including central retinal subfield thickness(CST),subfoveal choroidal thickness(SCT),foveal avascular zone(FAZ)and vessel density(VD)in the superficial and deep capillary plexuses in both the macular and optic disc(OD)regions were recorded.Data were analyzed using SPSS 15.0;descriptive statistics were reported,group comparisons were performed with Chisquare,Kruskal–Wallis,and Bonferroni-corrected Mann–Whitney U tests,and relationships were assessed using Spearman correlation,with statistical significance set at P<0.05.RESULTS:A total of 160 eyes of 160 participants(110 females and 50 males with mean age 38.7±9.9y)who don’t smoke were divided into five groups:never,occasional,monthly,weekly and daily drinkers.The mean CST was 216.6±14.2μm and the mean SCT was 358.9±84.5μm.There was no statistically significantly difference in CST and SCT among the groups(P=0.890,0.799).Foveal superficial capillary plexuses(SCPs)VD was higher in monthly drinkers compared to occasional drinkers(P=0.015).Foveal VD in deep capillary plexus was also higher in monthly drinkers than in never and occasional drinkers(P=0.004,0.006).Nasal SCPs VD at the OD was higher in monthly drinkers compared to never drinkers(P=0.005).There was no significant difference FAZ area among the groups(P=0.071).CONCLUSION:Both superficial and deep microvascular structures in the inferior quadrants of macula are positively correlated with frequency of alcohol use.Also in our study results is that the monthly drinker group has uniquely higher VDs in both macula and OD.This leads us to consider moderate alcohol consumption may also have protective effects on retinal microcirculation.展开更多
Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatmen...Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatment.Traditionally,diagnosis relies on optical coherence tomography imaging technology interpreted by ophthalmologists.However,this manual image interpretation is often slow and subjective.Therefore,developing automated segmentation for macular edema images is essential to enhance to improve the diagnosis efficiency and accuracy.Methods:In order to improve clinical diagnostic efficiency and accuracy,we proposed a SegNet network structure integrated with a convolutional block attention module(CBAM).This network introduces a multi-scale input module,the CBAM attention mechanism,and jump connection.The multi-scale input module enhances the network’s perceptual capabilities,while the lightweight CBAM effectively fuses relevant features across channels and spatial dimensions,allowing for better learning of varying information levels.Results:Experimental results demonstrate that the proposed network achieves an IoU of 80.127%and an accuracy of 99.162%.Compared to the traditional segmentation network,this model has fewer parameters,faster training and testing speed,and superior performance on semantic segmentation tasks,indicating its highly practical applicability.Conclusion:The C-SegNet proposed in this study enables accurate segmentation of Diabetic macular edema lesion images,which facilitates quicker diagnosis for healthcare professionals.展开更多
AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 group...AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 groups:Group A(implanted with the SN6CWS),Group B(implanted with the MI60),and Group C(implanted with the Aspira-aA).ELP measurements were obtained with swept-source optical coherence tomography(SS-OCT)at 1d,1wk,1mo,and 3mo postoperatively.Subjective refraction assessments were conducted at 1wk,1mo,and 3mo following surgery.RESULTS:The study included 189 eyes of 150 cataract patients(66 males).There were 77 eyes in Group A,55 eyes in Group B,and 57 eyes in Group C.The root mean square of the ELP(ELPRMS)within the initial 3mo was significantly lower for Group A than for Groups B and C.Refractive changes within Group A were not significant across the time points of 1wk,1mo,and 3mo.Conversely,both Group B and Group C demonstrated statistically significant shifts toward hyperopia from 1wk to 3mo postsurgery.CONCLUSION:Among the three IOLs examined,the SN6CWS IOL showes the greatest stability during the first 3mo postoperatively.Between 1wk and 3mo after surgery,notable hyperopic shifts are evident in eyes implanted with the MI60 and Aspira-aA IOLs,whereas refractive outcomes remain relatively constant in eyes implanted with SN6CWS IOLs.展开更多
AIM:To evaluate the differences and consistency of vault measurements obtained by Scheimpflug tomography(Pentacam),anterior segment optical coherence tomography(AS-OCT,CASIA II),and ultrasound biomicroscopy(UBM)follow...AIM:To evaluate the differences and consistency of vault measurements obtained by Scheimpflug tomography(Pentacam),anterior segment optical coherence tomography(AS-OCT,CASIA II),and ultrasound biomicroscopy(UBM)following implantable collamer lens(ICL)V4c implantation.METHODS:Vault measurements were acquired using three modalities:Pentacam,CASIA II AS-OCT,and UBM.Repeated-measures analysis of variance was used to compare the vault values obtained by the three devices.The correlation and consistency of measurements among the three instruments were assessed using the Pearson correlation coefficient,intraclass correlation coefficient(ICC),and Bland-Altman plots.RESULTS:This retrospective study enrolled 210 myopic eyes of 210 patients(158 women and 52 men)who underwent ICL implantation:108 eyes had a myopic ICL V4c implanted,and 102 eyes had a toric ICL V4c implanted.The mean vault values measured by Pentacam,CASIA II,and UBM were 452.64±204.20μm,538.57±203.54μm,and 560.95±227.54μm,respectively,with statistically significant differences among the three groups(P<0.05).Pearson correlation analysis showed strong positive correlations between vault values measured by different instruments(all P<0.001).ICC results indicated good consistency among the three measurement modalities(all P<0.001).Stratified analysis revealed that when the vault value was≤250μm,the correlation and consistency of measurements across the three instruments were lower than those in the medium and high vault subgroups.CONCLUSION:Vault values measured by Pentacam are lower than those obtained by CASIA II and UBM,with UBM yielding the highest mean vault values.Measurements from the three instruments are not interchangeable but can serve as mutual references due to their significant correlation and good overall consistency.Pentacam and CASIA II demonstrate the highest consistency in vault measurement.Notably,when the vault value is≤250μm,the consistency between Pentacam and the other two instruments decreases significantly.展开更多
AIM:To investigate the sex-specific correlation between systemic factors and retinal neurovascular alterations in individuals with type 1 diabetes mellitus(T1DM)who do not exhibit signs of diabetic retinopathy(DR).MET...AIM:To investigate the sex-specific correlation between systemic factors and retinal neurovascular alterations in individuals with type 1 diabetes mellitus(T1DM)who do not exhibit signs of diabetic retinopathy(DR).METHODS:A cohort participant without DR diagnosed with T1DM,underwent comprehensive ophthalmologic evaluation,optical coherence tomography angiography retinal structural and microvascular density analysis,and systemic parameter assessment.Multiple linear regression analysis was used to investigate the impact of systemic parameters on retinal alterations in distinct gender groups.RESULTS:A total of 182 individuals were included,consisting of 85 males(mean age 23.28±12.75y)and 97 females(mean age 22.98±13.68y).Males exhibited significantly greater thickness in both the internal retinal layer and the entire retina compared to females(P<0.01),whereas females had higher densities of deep retinal vessels and choroidal capillaries(P<0.05).Additionally,glycemic control was found to have a notable influence on retinal thickness in males(P<0.05),while insulin function had a more pronounced impact on retinal structure in females(P<0.01).Furthermore,a significant correlation was observed between thyroid function markers and retinal parameters in both male and female(P<0.05).CONCLUSION:Sex differences in alterations in retinal structure and microcirculation are observed in individuals with T1DM prior to the development of clinical DR,with a noted association between these changes and systemic parameters.展开更多
Advances in optical coherence tomography(OCT)technology allow a clear view of the vitreoretinal interface(VRI).The abnormality of the VRI is one of the common symptoms of high myopia,mainly including posterior vitreou...Advances in optical coherence tomography(OCT)technology allow a clear view of the vitreoretinal interface(VRI).The abnormality of the VRI is one of the common symptoms of high myopia,mainly including posterior vitreous detachment(PVD)and epiretinal membrane(ERM).They can cause severe damage to the structure and function of the retina,leading to permanent vision loss.Therefore,fully automated detection of abnormalities at the VRI is crucial for the management of high myopia.This paper presents a DS-YOLOv7 network aimed at accurately identifying abnormalities,including partial PVD,complete PVD,and ERM from retinal OCT images.Built upon the YOLOv7 network,the proposed model integrates the advanced dynamic snake convolution(DSConv)module to capture the curvilinear characteristics of lesions,and the mixture of attention and convolution(ACMix)module to improve the precision and robustness of feature extraction through effective fusion of self-attention mechanisms and convolution.Moreover,the introduction of the efficient complete intersection-over-union(ECIoU)loss function further enhances the coordinate regression capability of the model.Threefold cross-validation on a dataset with 1973 OCT B-scans from 46 patients shows that the DS-YOLOv7 achieved superior performance in vitreoretinal interface abnormality detection,with mAP@0.5 of 0.714,mAP@0.75 of 0.438,and mAP@0.5:0.95 of 0.424.The proposed model can provide an accurate and efficient diagnostic tool for patients with high myopia.展开更多
AIM:To explore the repeatability,reproducibility,and agreement in the measurement of the choroidal vascularity index(CVI)for different swept-source optical coherence tomography(OCT)devices and between OCT and OCT angi...AIM:To explore the repeatability,reproducibility,and agreement in the measurement of the choroidal vascularity index(CVI)for different swept-source optical coherence tomography(OCT)devices and between OCT and OCT angiography(OCTA)images.METHODS:Two swept-source OCT imaging systems,VG200I and Topcon DRI OCT Triton,were used to capture OCT and OCTA images in triplicate.The first and third images were taken by one operator,and the second image was taken by another operator.The built-in software was used to calculate the CVI from the OCTA images(CVI-OCTA),and a custom-designed algorithm was used to calculate the CVI from the OCT images(CVI-OCT).Repeatability and reproducibility were assessed with the intraclass correlation coefficient(ICC),and agreement between devices and between OCT and OCTA were evaluated with Bland-Altman analysis.RESULTS:Sixty-eight eyes from 35 adults(17 females)were included in the analysis.The average age of the participants was 23.6±2.3y,with an average spherical equivalent refraction of-3.08±2.47 D and an average AL of 25.21±1.20 mm.Both OCT devices demonstrated high repeatability and reproducibility in measuring the CVI-OCTA(all ICCs>0.894 across five choroidal regions)and CVI-OCT(all ICCs>0.838).Furthermore,the between-device agreement in measuring the CVI-OCT was good[mean difference(MD)ranging from-2.32%to-3.07%],but that in measuring the CVI-OCTA was poor(MD,1.48%to-7.43%).Additionally,the between-imaging agreement(CVI-OCTA versus CVI-OCT)was poor for both devices(Triton,MD,6.05%to 12.68%;VG200I,MD,6.67%to 12.09%).CONCLUSION:Both OCT devices and the two analytical methods demonstrate good stability.The inter-device consistency of CVI-OCT is good,while the inter-device consistency of CVI-OCTA and the consistency between the two analytical methods in the same device are both poor.展开更多
Retinal diseases are a serious threat to human visual health and their early diagnosis is crucial.Currently,most of the retinal disease diagnostic algorithms are based on a single imaging modality of fundus color phot...Retinal diseases are a serious threat to human visual health and their early diagnosis is crucial.Currently,most of the retinal disease diagnostic algorithms are based on a single imaging modality of fundus color photography(FCP)or optical coherence tomography(OCT).These methods can only reflect retinal diseases to a certain extent,ignoring the speci ficity of modalities between different imaging modalities.In this research,a newmulti-scale feature fusion network(MSFF-Net)model for multi-modal retinal image diagnosis is proposed.The MSFF-Net model employs a dualbranch architecture design,enabling efficient learning and extraction of multi-modal feature information related to retinal diseases from CFP and OCT images.MSFF-Net improves disease diagnosis by combining multi-scale features of CFP and OCT images.When evaluated on challenging datasets,the model achieved an accuracy of 95.00%and an F1-score of 95.24%for retinal disease diagnosis.Even under low-quality dataset conditions,it maintained robust performance,with diagnostic accuracy and F1-scores of 71.50%and 71.73%,respectively.In addition,the MSFFNet model outperformed eight state-of-the-art single and multi-modal models in the comparison experiments.The proposed MSFF-Net model provides ophthalmologists with a more accurate and efficient diagnostic pathway that helps them detect and treat retinal diseases earlier.展开更多
We demonstrate optical-carrier transfer over a 112-km single-span urban fiber link, By actively compensating the phase noise induced along the fiber link, a noise suppression of 55 dB at 1 Hz is obtained. A fractional...We demonstrate optical-carrier transfer over a 112-km single-span urban fiber link, By actively compensating the phase noise induced along the fiber link, a noise suppression of 55 dB at 1 Hz is obtained. A fractional frequency instability of 2.5× 10^-16 at i s is achieved, and reaching 7.5× 10^-20 at 10000 s. The system is stable and able to run for a long time. This work will contribute to optical frequency distribution and remote comparison among atomic clocks.展开更多
An improved zero-interpolation method with signal clipping to improve fiber nonlinearity tolerance in the long-haul coherent optical orthogonal frequency division multiplexing system （CO-OFDM） is presented. The new ...An improved zero-interpolation method with signal clipping to improve fiber nonlinearity tolerance in the long-haul coherent optical orthogonal frequency division multiplexing system （CO-OFDM） is presented. The new technique is implemented by interpolating zero subcarriers and selecting the odd subcarriers to carry data and clipping conventional CO-OFDM signal at zero. With such a scheme,the effect of fiber nonlinearity can be miti-gated,and the wanted signal carried on odd subcarriers is or-thogonal to clipping noise,which falls on even frequencies. Simu-lation shows that the system Q value is improved by more than 2 dB at the length of 960 km展开更多
文摘The linear transmission impairments,such as the timing offset(TO),frequency offset(FO),and chromatic dispersion(CD),are major factors of signal degradations in coherent optical fiber communication systems.The estimation and compensation of such impairments play significant roles in the receiver side digital signal processing(DSP)unit.In this paper,we propose to combat the linear impairments systematically(including TO,FO and CD)with a joint timefrequency signal processing by taking the advantage of fractional Fourier transform(FrFT).In view of geometrical analysis,TO/FO induces a shift in time/frequency coordinate and the CD leads to the rotation in the fractional domain.Both mathematical derivations and geometrical interpretations have been established to unveil the relationships between impairments and linear frequency modulated(LFM)training symbols(TSs).By considering a typical coherent optical orthogonal frequency-division multiplexing(COOFDM)transmission system,three kinds of linear impairments have been jointly estimated by simple geometric calculations using appropriately designed TS based on FrFTs.Simulation and experimental results confirmed the feasibility of time-frequency techniques with better accuracy,less complexity,and improved spectral efficiency.
文摘AIM:To analyze the effect of conbercept treatment on different types of macular edema secondary to retinal vein occlusion(RVO-ME)using optical coherence tomography(OCT)images.METHODS:This retrospective study included patients who first received conbercept injections for RVO-ME at Yijishan Hospital of Wannan Medical College from December 1,2017,to March 31,2022.Data on disease duration,age,hypertension,OCT images,central macular thickness(CMT),and best-corrected visual acuity(BCVA)were collected before and at 4-6 wk after treatment.Patients were divided into 4 groups according to different types of macular edema:cystoid macular edema(CME),sponge-like diffuse retinal thickening(SDRT),serous retinal detachment(SRD),and mixed type(FULL).Changes in CMT and visual acuity before and after treatment were compared among the groups to analyze differences in the effect of conbercept treatment on different ME types,and the effect of baseline CMT and visual acuity on post-treatment visual acuity.RESULTS:Totally 139 patients(139 eyes)were classified as having macular edema,including 62 males(44.6%)and 77 females(55.4%),with a mean age of 58.9±10.9 years,and they were divided into 4 groups based on different types of macular edema,including 54 cases(54 eyes)(mean age 59.6±11.1 years)in the CME group,23 cases(23 eyes;mean age 56.6±10.2 years)in the SDRT group,22 cases(22 eyes;mean age 57.8±12.0 years)in the SDR group,and 40 cases(40 eyes;mean age 60.0±10.7 years)in the FULL group.There were no significant differences in the duration of disease or age between groups(P>0.05).There was a significant difference in preoperative CMT between groups(P=0.01,one-way ANOVA),with the CMT in the FULL group being significantly greater than that in the SDRT group(P=0.03).There were no significant differences in pre-treatment visual acuity between the four groups(P=0.26).After conbercept treatment,the macular central recess thickness was reduced and visual acuity was improved in all four groups,among which the CMT in the CME and FULL groups was reduced significantly compared with the other two groups(P<0.05),and the visual acuity in the CME and SRD groups was improved significantly compared with the other two groups(P<0.05).Postoperative visual acuity was negatively correlated with preoperative CMT(P=0.044)and positively correlated with preoperative visual acuity(P<0.01).CONCLUSION:The efficacy of intravitreal conbercept in the treatment of RVO and macular edema may be related to the type of edema observed on OCT images,in which the efficacy is best in patients with CME but poor in patients with SDRT.
文摘Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.
基金supported by the National Natural Science Foundation of China(Nos.62375144 and 12404345)"the Fundamental Research Funds for the Central Universities",Nankai University(No.63241331).
文摘Accurate and early evaluation of dental physiological characteristics is essential for effective disease detection and management.Polarization-sensitive optical coherence tomography(PS-OCT)is a noninvasive high-resolution imaging technique that can obtain tooth structure and physiological features through intensity,retardation and degree of polarization uniformity(DOPU)images.In this study,we use the information provided by the PS-OCT system,especially the retardation information,to assess the physiological characteristics of teeth.In addition,we introduce a novel parameter—the rate of change of the retardation value(R)—to evaluate the magnitude of birefringence of enamel,which serves as an indicator of enamel health and mineralization.The results demonstrate that PS-OCT not only provides structural detail comparable to microcomputed tomography(microCT),but also yields additional physiological characteristics insights through polarization-based contrast.These findings highlight the strong potential of PS-OCT for early diagnosis,functional evaluation and personalized monitoring in dental care.
基金Supported by National Natural Science Foundation of Guangdong,China(No.2020A1515010829,No.2023A1515011652,No.2025A1515012389)Science and Technology Program of Guangzhou,China(No.2025A03J4033).
文摘AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopic children.METHODS:AL,steep keratometry(K),flat K,posterior corneal keratometry(PK),total keratometry(TK),anterior chamber depth(ACD),horizontal corneal diameter(CD),and central corneal thickness(CCT)were obtained using IOL Master 700 and Pentacam AXL.The agreement between the devices was evaluated using intraclass correlation coefficients(ICC),Bland-Altman plots,and astigmatism vector analysis.RESULTS:Totally 175 myopic children(48.5%male)with a mean age of 10.29±2.14y were enrolled.The ICC and Bland-Altman plots indicated a satisfactory agreement for AL,ACD,and CCT.The mean difference in CD of-0.31±0.30 mm was considered clinically significant(>0.2 mm).Additionally,measurements of K and TK obtained from the IOL Master 700 showed good agreement.Nevertheless,there were clinically significant differences observed in PK,simulated keratometry(simK),total cornea power,and astigmatism(at least 10%of the cases with a difference of>10 degrees in meridian)between the two devices.CONCLUSION:The study findings demonstrate a significant difference in K,PK,astigmatism,and CD,indicating that the two optical biometers cannot be considered interchangeable.Therefore,it is recommended to utilize one kind device for follow-up examinations in myopic children.
文摘AIM:To assess the current research status and emerging trends of the choriocapillaris(CC)by bibliometric analysis.METHODS:Publications spanning from January 2013 to May 2023 were retrieved on June 27th,2023,using the Web of Science Core Collection.Bibliometric and visualized analyses were performed employing the bibliometrix,CiteSpace and VOSviewer.RESULTS:A total of 1563 papers met the inclusion criteria,and a publication growth trend was observed.The United States was the leading country in the CC field.Retina and Investigative Ophthalmology&Visual Science stood out as highly impactful and prolific journals.Research topics in the CC field encompassed choroidal neovascularization,choroidal thickness,central serous chorioretinopathy,agerelated macular degeneration,myopia,choroidal vascularity index,and diabetic retinopathy,based on the co-citation analysis.The keyword“high myopia”experienced a burst lasting until 2023.CONCLUSION:In the past decade,research in the field of CC has flourished due to recent advancements in choroidal imaging;with focus shifting towards elucidating its role in various diseases.This will provide novel insights into managing chorioretinal diseases and vision-preserving interventions.
基金supported by the financial support received from the Indian Council of Medical Research-Department of Health Research(ICMRDHR-CoE-5/3/8/5/2019/I-MDMS)Medical Device and Diagnostics Mission Secretariat(MDMS)and Foundation for Centre for Healthcare Entrepreneurship(CfHE).
文摘Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making.
文摘AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patients diagnosed with MS and a control group of 43 healthy hospital staff matched in terms of age and sex at Iran University,department of neurology and ophthalmology from March 2020 to March 2021.The ophthalmic parameters of each patient were recorded,and optical coherence tomography was used to evaluate the retinal thickness in the layers.RESULTS:This study enrolled a total of 85 participants,with a mean age of 40.44±11.52 years,including 61 females(72%).The control group consisted of 43 individuals with a mean age of 39.49±11.07 years,while the MS group comprised 42 participants with a mean age of 41.40±12.01 years.The mean disease duration in the MS group was 8.45±6.04 a.The thickness of the ganglion cell layer in the right eye was significantly lower in the MS group compared to the control group(P=0.034).In addition,except for the left nasal sector(P=0.106),the mean peripapillary neurofibrillation in all examined sectors were significantly lower in the MS group than in the control group(P<0.05).The average vessel density in both the deep and superficial capillary plexuses across all regions of both eyes was lower in the MS group than in the control group,with all comparisons for the superficial capillary plexus showing statistical significance(P<0.05 for all except the left nasal sector).CONCLUSION:The thickness of the retina of patients with MS is significantly reduced.Therefore,optical coherence tomography results can be used as a reliable tool to evaluate disease progression and prognosis in MS patients.
文摘AIM:To investigate the association between anti-DFS70 antibody positivity and ocular parameters,specifically,the choroidal vascularity index(CVI)and other optical coherence tomography(OCT)metrics,in a healthy population.METHODS:This age-and sex-matched case-control study enrolled 84 healthy individuals with positive anti-DFS70 antibody findings and 84 healthy negative controls.All participants underwent detailed ophthalmological examinations,including biometry and OCT imaging.Anti-DFS70 positivity was determined by indirect immunofluorescence and scored semi-quantitatively(1+to 3+).CVI was calculated from OCT images using a standardized protocol with Image J software.Statistical analyses,including Student’s t-test,Mann-Whitney U test,Spearman correlation,and logistic regression,were used to compare groups and identify predictive factors.RESULTS:The individuals who tested positive and negative for anti-DFS70 included in the study were matched for age(median age=47y)and sex(F:M=7:1).CVI was significantly lower in the anti-DFS70-positive group compared to the negative group.A higher anti-DFS70 antibody titer was significantly associated with decreased subfoveal and nasal choroidal thickness(P=0.016 and P=0.014,respectively).In univariate regression analysis,CVI was the only significant predictor of anti-DFS70 positivity[odds ratio(OR)=0.02,P=0.025].Multivariate analysis revealed a positive correlation between macular thinning outside the subfoveal area and anti-DFS70 status(P<0.05).CONCLUSION:Our study demonstrates a novel association between anti-DFS70 antibody positivity and reduced choroidal vascularity in healthy individuals.These findings suggest that anti-DFS70 antibodies may be associated with subtle choroidal vascular changes detectable by OCT,even in asymptomatic individuals.Further longitudinal research is warranted to clarify the underlying mechanisms and long-term clinical significance of these ocular changes.
基金Central High-Level Traditional Chinese Medicine Hospital Project of Eye Hospital China Academy of Chinese Medical Science(No.GSP5-83,No.GSP4-02No.GSP5-06)+1 种基金Supported by National Natural Science Foundation of China(General ProgramNo.82474582).
文摘AIM:To evaluate the therapeutic effects of ranibizumab on optic disc and macular microvascular perfusion in central retinal vein occlusion(CRVO)with macular edema(ME).METHODS:Optical coherence tomography angiology(OCTA)parameters,including optic disc vessel density(VD;including whole-disc VD,intra-disc VD,and peripapillary VD),superficial/deep capillary plexus(SCP/DCP)VD,and central macular thickness(CMT)were analyzed.Additional assessments included best-corrected visual acuity(BCVA)via Early Treatment Diabetic Retinopathy Study(ETDRS)chart and hemorheological profiling.CRVO patients received monthly intravitreal ranibizumab injections for three consecutive months.Pre-and post-treatment parameters were statistically compared.RESULTS:The study comprised 60 CRVO-ME patients(28 males;32 females),aged 50-78y(mean 63.3±7.6y)and 60 age-/sex-matched healthy controls.As compared with participants exhibiting normal funduscopic findings,CRVO patients demonstrated significantly elevated levels of low-shear-rate whole blood viscosity(LSR-WBV),high-shearrate whole blood viscosity(HSR-WBV),and aggregation index(AI,all P<0.05).In CRVO-affected eyes,vertical cupto-disc(C/D)ratio and optic cup volume were significantly smaller,whereas retinal nerve fiber layer(RNFL)thickness was significantly greater,compared to both unaffected contralateral eyes and normal control eyes(all P<0.05).Following treatment,VD of the entire optic disc(P<0.05),intra-disc VD(P<0.05),and peripapillary VD(P<0.05)all increased significantly relative to baseline.CMT decreased significantly(P<0.05),whereas macular SCP-VD and macular DCP-VD showed non-significant slight reductions(P>0.05).At baseline,BCVA of CRVO eyes correlated with whole-disc VD(r=-0.276,P=0.033),intra-disc VD(r=-0.342,P=0.009),and peripapillary VD(r=-0.335,P=0.007),with intra-disc VD demonstrating the strongest association.Besides,BCVA improvement,after the treatment,correlated positively with whole-disc VD(r=0.342,P=0.008)and intradisc VD(r=0.396,P=0.002).CONCLUSION:Optic disc blood perfusion is more closely associated with visual acuity than macular perfusion,suggesting intra-disc VD may serve as a potential biomarker for monitoring visual acuity changes in CRVO.Multiple ranibizumab injections significantly improve optic disc perfusion but may have exerted detrimental effects on the macula.CRVO patients shows higher hemorheological parameters than those with normal fundi.Reduced vertical C/D ratio and optic cup volume may be linked to CRVO incidence,potentially acting as susceptibility factors.
文摘AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This observational clinical study utilized a cross-sectional and prospective design,focusing on chronic alcohol consumers alongside a non-consuming control group.OCT/OCTA imaging parameters including central retinal subfield thickness(CST),subfoveal choroidal thickness(SCT),foveal avascular zone(FAZ)and vessel density(VD)in the superficial and deep capillary plexuses in both the macular and optic disc(OD)regions were recorded.Data were analyzed using SPSS 15.0;descriptive statistics were reported,group comparisons were performed with Chisquare,Kruskal–Wallis,and Bonferroni-corrected Mann–Whitney U tests,and relationships were assessed using Spearman correlation,with statistical significance set at P<0.05.RESULTS:A total of 160 eyes of 160 participants(110 females and 50 males with mean age 38.7±9.9y)who don’t smoke were divided into five groups:never,occasional,monthly,weekly and daily drinkers.The mean CST was 216.6±14.2μm and the mean SCT was 358.9±84.5μm.There was no statistically significantly difference in CST and SCT among the groups(P=0.890,0.799).Foveal superficial capillary plexuses(SCPs)VD was higher in monthly drinkers compared to occasional drinkers(P=0.015).Foveal VD in deep capillary plexus was also higher in monthly drinkers than in never and occasional drinkers(P=0.004,0.006).Nasal SCPs VD at the OD was higher in monthly drinkers compared to never drinkers(P=0.005).There was no significant difference FAZ area among the groups(P=0.071).CONCLUSION:Both superficial and deep microvascular structures in the inferior quadrants of macula are positively correlated with frequency of alcohol use.Also in our study results is that the monthly drinker group has uniquely higher VDs in both macula and OD.This leads us to consider moderate alcohol consumption may also have protective effects on retinal microcirculation.
基金supported by the Guangdong Pharmaceutical University 2024 Higher Education Research Projects(GKP202403,GMP202402)the Guangdong Pharmaceutical University College Students’Innovation and Entrepreneurship Training Programs(Grant No.202504302033,202504302034,202504302036,and 202504302244).
文摘Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatment.Traditionally,diagnosis relies on optical coherence tomography imaging technology interpreted by ophthalmologists.However,this manual image interpretation is often slow and subjective.Therefore,developing automated segmentation for macular edema images is essential to enhance to improve the diagnosis efficiency and accuracy.Methods:In order to improve clinical diagnostic efficiency and accuracy,we proposed a SegNet network structure integrated with a convolutional block attention module(CBAM).This network introduces a multi-scale input module,the CBAM attention mechanism,and jump connection.The multi-scale input module enhances the network’s perceptual capabilities,while the lightweight CBAM effectively fuses relevant features across channels and spatial dimensions,allowing for better learning of varying information levels.Results:Experimental results demonstrate that the proposed network achieves an IoU of 80.127%and an accuracy of 99.162%.Compared to the traditional segmentation network,this model has fewer parameters,faster training and testing speed,and superior performance on semantic segmentation tasks,indicating its highly practical applicability.Conclusion:The C-SegNet proposed in this study enables accurate segmentation of Diabetic macular edema lesion images,which facilitates quicker diagnosis for healthcare professionals.
基金Supported by the Zhejiang Medical Health Science and Technology Project(No.2021KY217)the Basic Public Welfare Research Project of Wenzhou Municipal Science and Technology Bureau(No.2024Y1221).
文摘AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 groups:Group A(implanted with the SN6CWS),Group B(implanted with the MI60),and Group C(implanted with the Aspira-aA).ELP measurements were obtained with swept-source optical coherence tomography(SS-OCT)at 1d,1wk,1mo,and 3mo postoperatively.Subjective refraction assessments were conducted at 1wk,1mo,and 3mo following surgery.RESULTS:The study included 189 eyes of 150 cataract patients(66 males).There were 77 eyes in Group A,55 eyes in Group B,and 57 eyes in Group C.The root mean square of the ELP(ELPRMS)within the initial 3mo was significantly lower for Group A than for Groups B and C.Refractive changes within Group A were not significant across the time points of 1wk,1mo,and 3mo.Conversely,both Group B and Group C demonstrated statistically significant shifts toward hyperopia from 1wk to 3mo postsurgery.CONCLUSION:Among the three IOLs examined,the SN6CWS IOL showes the greatest stability during the first 3mo postoperatively.Between 1wk and 3mo after surgery,notable hyperopic shifts are evident in eyes implanted with the MI60 and Aspira-aA IOLs,whereas refractive outcomes remain relatively constant in eyes implanted with SN6CWS IOLs.
基金Supported by the National Natural Science Foundation of China(No.82171095)the Project of Shanghai Science and Technology(No.23XD1400500)the Research Fund of Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital(No.24QNPY049).
文摘AIM:To evaluate the differences and consistency of vault measurements obtained by Scheimpflug tomography(Pentacam),anterior segment optical coherence tomography(AS-OCT,CASIA II),and ultrasound biomicroscopy(UBM)following implantable collamer lens(ICL)V4c implantation.METHODS:Vault measurements were acquired using three modalities:Pentacam,CASIA II AS-OCT,and UBM.Repeated-measures analysis of variance was used to compare the vault values obtained by the three devices.The correlation and consistency of measurements among the three instruments were assessed using the Pearson correlation coefficient,intraclass correlation coefficient(ICC),and Bland-Altman plots.RESULTS:This retrospective study enrolled 210 myopic eyes of 210 patients(158 women and 52 men)who underwent ICL implantation:108 eyes had a myopic ICL V4c implanted,and 102 eyes had a toric ICL V4c implanted.The mean vault values measured by Pentacam,CASIA II,and UBM were 452.64±204.20μm,538.57±203.54μm,and 560.95±227.54μm,respectively,with statistically significant differences among the three groups(P<0.05).Pearson correlation analysis showed strong positive correlations between vault values measured by different instruments(all P<0.001).ICC results indicated good consistency among the three measurement modalities(all P<0.001).Stratified analysis revealed that when the vault value was≤250μm,the correlation and consistency of measurements across the three instruments were lower than those in the medium and high vault subgroups.CONCLUSION:Vault values measured by Pentacam are lower than those obtained by CASIA II and UBM,with UBM yielding the highest mean vault values.Measurements from the three instruments are not interchangeable but can serve as mutual references due to their significant correlation and good overall consistency.Pentacam and CASIA II demonstrate the highest consistency in vault measurement.Notably,when the vault value is≤250μm,the consistency between Pentacam and the other two instruments decreases significantly.
基金Supported by Natural Science Foundation of Hunan Province(No.2023JJ70017No.2025JJ50627)Peak Climbing Project of Optometry Hospital Affiliated to Wenzhou Medical University。
文摘AIM:To investigate the sex-specific correlation between systemic factors and retinal neurovascular alterations in individuals with type 1 diabetes mellitus(T1DM)who do not exhibit signs of diabetic retinopathy(DR).METHODS:A cohort participant without DR diagnosed with T1DM,underwent comprehensive ophthalmologic evaluation,optical coherence tomography angiography retinal structural and microvascular density analysis,and systemic parameter assessment.Multiple linear regression analysis was used to investigate the impact of systemic parameters on retinal alterations in distinct gender groups.RESULTS:A total of 182 individuals were included,consisting of 85 males(mean age 23.28±12.75y)and 97 females(mean age 22.98±13.68y).Males exhibited significantly greater thickness in both the internal retinal layer and the entire retina compared to females(P<0.01),whereas females had higher densities of deep retinal vessels and choroidal capillaries(P<0.05).Additionally,glycemic control was found to have a notable influence on retinal thickness in males(P<0.05),while insulin function had a more pronounced impact on retinal structure in females(P<0.01).Furthermore,a significant correlation was observed between thyroid function markers and retinal parameters in both male and female(P<0.05).CONCLUSION:Sex differences in alterations in retinal structure and microcirculation are observed in individuals with T1DM prior to the development of clinical DR,with a noted association between these changes and systemic parameters.
基金supported by the National Natural Science Foundation of China(62271337,62371326,and 62371328)the National Key Research and Development Program of China(2019FYC1710204)+1 种基金the National Clinical Key Specialty Construction Project(10000015Z155080000004)the Natural Science Foundation of Jiangsu Province(BK20231310).
文摘Advances in optical coherence tomography(OCT)technology allow a clear view of the vitreoretinal interface(VRI).The abnormality of the VRI is one of the common symptoms of high myopia,mainly including posterior vitreous detachment(PVD)and epiretinal membrane(ERM).They can cause severe damage to the structure and function of the retina,leading to permanent vision loss.Therefore,fully automated detection of abnormalities at the VRI is crucial for the management of high myopia.This paper presents a DS-YOLOv7 network aimed at accurately identifying abnormalities,including partial PVD,complete PVD,and ERM from retinal OCT images.Built upon the YOLOv7 network,the proposed model integrates the advanced dynamic snake convolution(DSConv)module to capture the curvilinear characteristics of lesions,and the mixture of attention and convolution(ACMix)module to improve the precision and robustness of feature extraction through effective fusion of self-attention mechanisms and convolution.Moreover,the introduction of the efficient complete intersection-over-union(ECIoU)loss function further enhances the coordinate regression capability of the model.Threefold cross-validation on a dataset with 1973 OCT B-scans from 46 patients shows that the DS-YOLOv7 achieved superior performance in vitreoretinal interface abnormality detection,with mAP@0.5 of 0.714,mAP@0.75 of 0.438,and mAP@0.5:0.95 of 0.424.The proposed model can provide an accurate and efficient diagnostic tool for patients with high myopia.
基金Supported by the National Key Research and Development Program of China(No.2022YFC3502503)the Medical and Health Science and Technology Project of the Zhejiang Provincial Health Commission of China(No.2022PY072).
文摘AIM:To explore the repeatability,reproducibility,and agreement in the measurement of the choroidal vascularity index(CVI)for different swept-source optical coherence tomography(OCT)devices and between OCT and OCT angiography(OCTA)images.METHODS:Two swept-source OCT imaging systems,VG200I and Topcon DRI OCT Triton,were used to capture OCT and OCTA images in triplicate.The first and third images were taken by one operator,and the second image was taken by another operator.The built-in software was used to calculate the CVI from the OCTA images(CVI-OCTA),and a custom-designed algorithm was used to calculate the CVI from the OCT images(CVI-OCT).Repeatability and reproducibility were assessed with the intraclass correlation coefficient(ICC),and agreement between devices and between OCT and OCTA were evaluated with Bland-Altman analysis.RESULTS:Sixty-eight eyes from 35 adults(17 females)were included in the analysis.The average age of the participants was 23.6±2.3y,with an average spherical equivalent refraction of-3.08±2.47 D and an average AL of 25.21±1.20 mm.Both OCT devices demonstrated high repeatability and reproducibility in measuring the CVI-OCTA(all ICCs>0.894 across five choroidal regions)and CVI-OCT(all ICCs>0.838).Furthermore,the between-device agreement in measuring the CVI-OCT was good[mean difference(MD)ranging from-2.32%to-3.07%],but that in measuring the CVI-OCTA was poor(MD,1.48%to-7.43%).Additionally,the between-imaging agreement(CVI-OCTA versus CVI-OCT)was poor for both devices(Triton,MD,6.05%to 12.68%;VG200I,MD,6.67%to 12.09%).CONCLUSION:Both OCT devices and the two analytical methods demonstrate good stability.The inter-device consistency of CVI-OCT is good,while the inter-device consistency of CVI-OCTA and the consistency between the two analytical methods in the same device are both poor.
基金supported by the National Natural Science Foundation of China(Nos.82472104 and U24B2053)the Natural Science Basic Research Program of Shaanxi(No.2025JC-JCQN-023)+2 种基金the Key Core Technology Research and Development of Shaanxi(No.2024QY2-GJHX-03)the Innovation Capability Support Program of Shaanxi(Program No.2023-CX-TD-54)the Xidian University Specially Funded Project for Interdisciplinary Exploration(No.TZJHF202510).
文摘Retinal diseases are a serious threat to human visual health and their early diagnosis is crucial.Currently,most of the retinal disease diagnostic algorithms are based on a single imaging modality of fundus color photography(FCP)or optical coherence tomography(OCT).These methods can only reflect retinal diseases to a certain extent,ignoring the speci ficity of modalities between different imaging modalities.In this research,a newmulti-scale feature fusion network(MSFF-Net)model for multi-modal retinal image diagnosis is proposed.The MSFF-Net model employs a dualbranch architecture design,enabling efficient learning and extraction of multi-modal feature information related to retinal diseases from CFP and OCT images.MSFF-Net improves disease diagnosis by combining multi-scale features of CFP and OCT images.When evaluated on challenging datasets,the model achieved an accuracy of 95.00%and an F1-score of 95.24%for retinal disease diagnosis.Even under low-quality dataset conditions,it maintained robust performance,with diagnostic accuracy and F1-scores of 71.50%and 71.73%,respectively.In addition,the MSFFNet model outperformed eight state-of-the-art single and multi-modal models in the comparison experiments.The proposed MSFF-Net model provides ophthalmologists with a more accurate and efficient diagnostic pathway that helps them detect and treat retinal diseases earlier.
基金Supported by the Special Fund for Major Scientific Equipment and Instrument Development of the National Natural Science Foundation of China under Grant No 61127901the National Natural Science Foundation of China under Grant Nos 10225417,11273024,61025023 and 91636101+3 种基金the Young Scientists Fund of the National Natural Science Foundation of China under Grant No 11403031the Key Deployment Project of the Chinese Academy of Sciences under Grant No KJZD-EW-W02the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDB21030800the National Key Research and Development Program of China under Grant Nos 2016YFF0200200 and 2016YFF0200205
文摘We demonstrate optical-carrier transfer over a 112-km single-span urban fiber link, By actively compensating the phase noise induced along the fiber link, a noise suppression of 55 dB at 1 Hz is obtained. A fractional frequency instability of 2.5× 10^-16 at i s is achieved, and reaching 7.5× 10^-20 at 10000 s. The system is stable and able to run for a long time. This work will contribute to optical frequency distribution and remote comparison among atomic clocks.
基金Supported by the National Natural Science Foundation of China (60871075)
文摘An improved zero-interpolation method with signal clipping to improve fiber nonlinearity tolerance in the long-haul coherent optical orthogonal frequency division multiplexing system （CO-OFDM） is presented. The new technique is implemented by interpolating zero subcarriers and selecting the odd subcarriers to carry data and clipping conventional CO-OFDM signal at zero. With such a scheme,the effect of fiber nonlinearity can be miti-gated,and the wanted signal carried on odd subcarriers is or-thogonal to clipping noise,which falls on even frequencies. Simu-lation shows that the system Q value is improved by more than 2 dB at the length of 960 km
