Melanoma,characterized by high mortality,rapid development and accompanied with angio-genesis is the most typical malignant tumor in skin cancer.Hence,the detection of blood vessels is of much significanoe.The early v...Melanoma,characterized by high mortality,rapid development and accompanied with angio-genesis is the most typical malignant tumor in skin cancer.Hence,the detection of blood vessels is of much significanoe.The early vascular network has small scale.If we remove the tumor early and biopsy it,it will increase the spread of the cancer cells and infection and bleeding.In this case,we presented a new angiography method.A high-resolution OCT system for noninvasive an-giographic imaging of early skin melanoma-Swept Source Optical Coberence Tomography Angiography(SS-OCTA)is proposed.With a high lateral resolution of 10pm in vrivo tomographic angiography,SS-OCTA is used to image and identify the morphology of the early tumor blood vessels.In addition,a control group experiment is conducted to observe the growth of melanoma in the process of rupture,malormation of micro-vessels.The results of the analysis and statistical test(P<0.05)are statistically signifcant.展开更多
In this work,a new structure is used to enhance the nonlinear effect in the cavity,which improvesthe performance of the 1.3μm broadband swept source.The swept source adopts a semiconductoroptical amplifier(SOA),a cir...In this work,a new structure is used to enhance the nonlinear effect in the cavity,which improvesthe performance of the 1.3μm broadband swept source.The swept source adopts a semiconductoroptical amplifier(SOA),a circulator,a coupler,and a tunable filter.In the structure,the lightpasses through the nonlinear medium(SOA)twice in two opposite directions,which excites thenonlinear ffect and increases the performance of the swept source.The tunable filter is based on apolygon rotating mirror and gratings.Traditionally,multiple SOAs are adopted to improve thesweep range and the optical power,which increases the cost and complexity of the swept source.The method proposed in this paper can improve the spectral range and optical power of the sweptsources without additional accessories.For the short-cavity swept source,the power increasesfrom 6 mW to 7.7 mW,and the sweep range increases from 98 nm to 120 nm.The broadband swept sources could have wide applications in biomedical imaging,sensor system,measurementand so on.展开更多
In this work, we investigate the methods to improve the performance of the swept source at 1.0 μm based on a polygon scanner, including in-cavity parameters and booster structures out of the cavity. The three in-cavi...In this work, we investigate the methods to improve the performance of the swept source at 1.0 μm based on a polygon scanner, including in-cavity parameters and booster structures out of the cavity. The three in-cavity parameters are the cavity length, the rotating speed of the polygon scanner, and the in-cavity energy. With the decrease of cavity length, the spectrum bandwidth becomes wider and the duty cycle becomes higher.With the increase of the rotating speed of the polygon, the spectrum bandwidth becomes narrower, and the duty cycle becomes lower but the repetition rate becomes higher. With more energy in-cavity, the spectrum bandwidth becomes wider and the duty cycle becomes higher. The booster structures include the buffered structure, secondary amplifier, and dual-semiconductor optical amplifier configuration, which are used to increase the sweep frequency to 86 kHz, the output power to 18 mW, and the tuning bandwidth to 131 nm, respectively.展开更多
Background:There are two forms of system implementation of optical coherence tomography angiography(OCTA)in ophthalmic imaging,i.e.,spectral domain(SD-)and swept source OCTA(SS-OCTA).The purpose of this paper is to co...Background:There are two forms of system implementation of optical coherence tomography angiography(OCTA)in ophthalmic imaging,i.e.,spectral domain(SD-)and swept source OCTA(SS-OCTA).The purpose of this paper is to compare the SD-OCTA and SS-OCTA for elucidating structural and vascular features associated with central serous retinopathy(CSR),and to evaluate the effects of CSR on SD-and SS-OCTA’s imaging capabilities.Methods:Normal subjects and CSR patients were imaged by SD-and SS-OCTA using 3×3 mm and 6×6 mm scan patterns.OCT signal strengths at the superficial retina,deep retina,Sattler’s layer and Haller’s layer were used to compare the ability of SD-and SS-OCTA to image structural features.In addition,the ability to acquire angiograms were discussed by evaluating retinal vessel density.Central serous volume(CSV)was measured and it was correlated with difference in signal strengths(ΔS)between two OCTA devices.Results:Seven normal eyes and seven diseased eyes were recruited.Results showed no significant differences between SD-and SS-OCT in detecting structural features of the retinal layer according to the paired t-test.However,when imaging the Sattler’s layer for normal eyes,a significant difference is found between SD-and SS-OCT(p<0.0001 for 3×3 mm scan,and p=0.0002 for 6×6 mm);while for CSR eyes,the corresponding values were p<0.0001 and p=0.0003,respectively.At Haller’s layer for normal eyes,the corresponding values were p=0.0004 and p=0.0014;and for CSR eyes,p=0.0004 and p<0.0001,respectively.A strong correlation betweenΔS and CSV was observed in the Sattler’s layer(3×3 mm–p=0.0031 and R^(2)=0.951;6×6 mm–p=0.0075 and R^(2)=0.911)and Haller’s layer(3×3 mm–p=0.0026 and R^(2)=0.955;6×6 mm–p=0.0013 and R^(2)=0.972).Conclusions:The results suggest no differences between SD-and SS-OCTA for imaging the retinal layers however,when imaging beyond retinal layers,SS-OCTA appears advantageous in detecting returning signals.In CSR cases,the CSV may have an impact on sub-CSR tissue imaging and appears to have more impact on SD-than SS-OCTA.展开更多
A novel broad tunable bandwidth and narrow instantaneous line-width linear swept laser source using combined tunable filters working at 1,300 nm center wavelength is proposed.The combined filters consist of a fiber Fa...A novel broad tunable bandwidth and narrow instantaneous line-width linear swept laser source using combined tunable filters working at 1,300 nm center wavelength is proposed.The combined filters consist of a fiber FabryPerot tunable filter and a tunable filter based on diffractive grating with scanning polygon mirror.In contrast to traditional method using single tunable filter,the trade-off between bandwidth and instantaneous line-width is alleviated.Parallel implementation of two semiconductor optical amplifiers with different wavelength range is adopted in the laser resonator for broadband light amplification.The Fourier domain mode locking swept laser source with combined tunable filters offers broadband tunable range with narrow instantaneous line-width,which is especially benefiting for high-quality optical frequency domain imaging.The proposed Fourier domain mode locking swept laser source provides a tuning range of 160 nm with instantaneous line-width of about 0.01nm at sweeping rate of 15 kHz,a finesse of 16,000 is thus achieved.展开更多
AIM: To compare the ocular fundus features of highly myopic eyes with and without macular Bruch’s membrane(BM) defects and investigate the associations between macular BM defects and other myopic lesions.METHODS: Thi...AIM: To compare the ocular fundus features of highly myopic eyes with and without macular Bruch’s membrane(BM) defects and investigate the associations between macular BM defects and other myopic lesions.METHODS: This retrospective, observational case series included 262 eyes(139 patients) with high myopia(HM) refractive error ≥-6.0 diopters(D) or axial length ≥26.5 mm from March 2019 to December 2019.The patients underwent a comprehensive ophthalmic examination, including sweptsource optical coherence tomography(SS-OCT).The features of macular BM defects and other ocular fundus lesions were examined in OCT images.RESULTS: Totally 51 eyes(19.5%) were detected with macular BM defects, which were characterized by a lack of BM, retinal pigment epithelium(RPE), and an almost complete loss of photoreceptors or choriocapillaris.Eyes with macular BM defects had worse best-corrected visual acuity(BCVA) than those without(P<0.001).Dome-shaped macula(DSM, P=0.042), retinal cysts(P=0.006), choroidal neovascularization(CNV, P<0.001), choroidal defects and abnormality(P=0.003), scleral defects(P=0.015), scleral deformation(P=0.005), posterior staphyloma(P=0.011), and perforating vessels(P<0.001) occurred more frequently in eyes with macular BM defects.In multivariate analysis, the presence of macular BM defects remained the significant association with presence of DSM(P=0.013), scleral defects(P=0.015), posterior staphyloma(P=0.001), perforating vessels(P<0.001) and CNV(P=0.004).CONCLUSION: Macular BM defects has a prevalence of approximately 20% in HM and it has tight association with other myopic fundus lesions.BM might be crucial in the pathogenesis of myopic fundus lesions due to its biomechanical function.A comprehensive understanding of BM’s role is useful for further researches about myopic lesions.展开更多
Background:To evaluate the effect of orthokeratology on precision of measurements in children using a new swept-source optical coherence tomography(SS-OCT)optical biometer(OA-2000),and agreement between its measuremen...Background:To evaluate the effect of orthokeratology on precision of measurements in children using a new swept-source optical coherence tomography(SS-OCT)optical biometer(OA-2000),and agreement between its measurements and those provided by the commonly used IOLMaster based on partial coherence interferometry(PCI).Methods:This study recruited fifty-one eyes of 51 normal children(8–16 years).An operator took measurements with the two biometers.Then,a second operator took measurements with the SS-OCT biometer.After orthokeratology was performed for one month,the same operators repeated the same procedures.Axial length(AL),mean keratometry(Km)at 2.5 mm and 3.0 mm diameters(Km2.5 and Km3.0),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT)and corneal diameter(CD)were analyzed.Results:With the SS-OCT optical biometer,the test-retest repeatability of AL measurements was<0.06 mm.For all parameters,the coefficients of variation were<1.23%and the intraclass correlation coefficients were>0.95.The 95%limits of agreement of difference between the two devices for CD parameter were up to 1.53 mm.After orthokeratology,the fluctuation ranges of difference for Km3.0 measurement was 1.11 times higher than before orthokeratology,while the absolute values of difference for AL,Km2.5,ACD and CD measurements were comparable.Conclusions:Before and after orthokeratology,the SS-OCT biometer showed high repeatability and reproducibility for all measurements.Wearing orthokeratology contact lenses affected the agreement between SS-OCT and PCI biometers for Km3.0 measurements.The CD measurement showed poor agreement between the two devices.展开更多
Background:To measure the anterior and posterior segment structural features of acute primary angle-closure(APAC)eyes.Methods:A total of 36 subjects with unilateral APAC were recruited in this study.The ocular biometr...Background:To measure the anterior and posterior segment structural features of acute primary angle-closure(APAC)eyes.Methods:A total of 36 subjects with unilateral APAC were recruited in this study.The ocular biometric characteristics were measured by anterior segment optical coherence tomography(AS-OCT)and swept source optical coherence tomography(SS-OCT),respectively at baseline,2 weeks,and 1 month after surgical intervention.Results:At baseline,when compared with the fellow eyes,APAC-affected eyes showed significantly greater corneal thickness(P=0.004),shallower anterior chamber depth(ACD)(P<0.001),smaller anterior chamber area(ACA)(P=0.013),angle opening distance at 750μm from the scleral spur(AOD750)(P=0.002),trabecular-iris space area at 750μm from the scleral spur(TISA750)(P=0.033),angle recess area(ARA)(P=0.014),and iris area(IARE)(P=0.003),less iris curvature(ICURVE)(P=0.003),and larger lens vault(LV)(P=0.030).After intervention,the corneal thickness was significantly decreased at 1 month(P<0.001),while ACD,ACA,and AOD750 were significantly increased at 2 weeks and 1 month(all P<0.017).Changes in ACD were correlated with decreasing LV(P<0.05).The posterior segment parameters did not change over the 4-week period.Conclusions:When compared with the fellow eyes,APAC-affected eyes had greater corneal thickness,shallower anterior chamber,narrower angle,less ICURVE,and larger LV.After intervention,the corneal thickness was decreased,while the shallower anterior chamber was relieved to some extent.展开更多
Aims:This study describes vascular abnormalities in X-linked retinoschisis(XLRS)using fundus fluorescein angiography(FFA)and ultra-widefield swept-source optical coherence tomography angiography(UWF SS-OCTA)to better ...Aims:This study describes vascular abnormalities in X-linked retinoschisis(XLRS)using fundus fluorescein angiography(FFA)and ultra-widefield swept-source optical coherence tomography angiography(UWF SS-OCTA)to better understand the disease's vascular features and impact.Methods:A retrospective cross-sectional study was conducted on 26 XLRS patients(46 eyes).A comprehensive ophthalmic examination was performed,including FFA and UWF SS-OCTA.FFA abnormalities were divided into peripheral schisis-associated and optic disc-associated types.Results:The mean age of patients was 11.3±6.5 years.Macular schisis appeared in 97.8%of eyes,peripheral schisis in 89.1%,and peripheral bullous schisis(PBS)in 67.39%.Major vascular changes identified by FFA included dendritic capillary dilation/leakage(91.3%),internal residual vessel leakage(78.3%),and capillary dropout/ischemia(71.7%).Minor changes included zonal retinal pigment epithelium(RPE)proliferation(6.5%),bridging vessels(4.4%),and capillary sheathing(4.4%).peripapillary choroidal neovascularization(PPCNV)was noted in 10.9%and situs inversus of optic disc in 13.0%of eyes.Additionally,situs in versus of optic disc and zonal RPE proliferation were novel findings.Major FFA changes correlated with broader PBS(P=0.045)(P<0.001)(P=0.003).Clock hours of PBS were significant predictors for internal residual vessel leakage(OR=0.30,P=0.03).No significant correlation was found between gene mutation type and FFA abnormalities(P=0.539).Conclusions:This study highlighted the significant prevalence(95.7%)of vascular abnormalities in XLRS and emphasized the importance of combining FFA with UWF SS-OCTA for comprehensive evaluation,enhancing the understanding of XLRS pathophysiology and aiding in targeted treatment approaches.展开更多
Swept source optical coherence tomography(SS-OCT)is a new noninvasive technique for assessing tissue.Although it hasadvantages,such as being label-free,noninvasive,and with high resolution,it also has drawbacks:there ...Swept source optical coherence tomography(SS-OCT)is a new noninvasive technique for assessing tissue.Although it hasadvantages,such as being label-free,noninvasive,and with high resolution,it also has drawbacks:there has been no indepth research into identifying the driving of swept source.Based on preliminary research,we demonstrate a novel drivingmodulation method of a fiber Fabry–Perot tunable filter ranging phase adjustable as a tool for making bandwidth compensation of a swept laser source.This novel method is analyzed in detail;a swept laser source with a sweep rate of100.5 kHz over a range of 152.25 nm and at a center wavelength of 1335.45 nm is demonstrated.展开更多
The depth ranges of typical implementations of Fourier domain optical coherence tomography （FDOCT）, including spectral domain OCT （SDOCT） and swept source OCT （SSOCT）, are limited to several millimeters. To exte...The depth ranges of typical implementations of Fourier domain optical coherence tomography （FDOCT）, including spectral domain OCT （SDOCT） and swept source OCT （SSOCT）, are limited to several millimeters. To extend the depth range of current OCT systems, two novel systems with ultralong depth range were developed in this study. One is the orthogonal dispersive SDOCT （OD-SDOCT）, and the other is the recirculated swept source （R-SS） interferometer/OCT. No compromise between depth range and depth resolution is required in both systems. The developed OD-SDOCT system realized the longest depth range （over 100 mm） ever achieved by SDOCT, which is ready to be modified for depth-encoded parallel imaging on multiple sites. The developed R-SS interferometer achieved submicron precision within a depth range of 30mm, holding potential in real-time contact-free on-axis metrology of complex optical sys- tems.展开更多
基金supported by the Jiangsu Province Science Fund for Distinguished Young Scholars(BK20060010)the Frontier Science Research project of the Chinese Academy of Sciences(QYZDBS-SWJSC03)+2 种基金the National Natural Science Foundation of China(61675226)the National Key R&D Program of China(2017YFC0108200,2017YFB0403700)the Jiangsu Province Key R&D Program(BE2018667).
文摘Melanoma,characterized by high mortality,rapid development and accompanied with angio-genesis is the most typical malignant tumor in skin cancer.Hence,the detection of blood vessels is of much significanoe.The early vascular network has small scale.If we remove the tumor early and biopsy it,it will increase the spread of the cancer cells and infection and bleeding.In this case,we presented a new angiography method.A high-resolution OCT system for noninvasive an-giographic imaging of early skin melanoma-Swept Source Optical Coberence Tomography Angiography(SS-OCTA)is proposed.With a high lateral resolution of 10pm in vrivo tomographic angiography,SS-OCTA is used to image and identify the morphology of the early tumor blood vessels.In addition,a control group experiment is conducted to observe the growth of melanoma in the process of rupture,malormation of micro-vessels.The results of the analysis and statistical test(P<0.05)are statistically signifcant.
基金supported by the National Key R&D Program of China(2016YFF0102003 and 2016YFF0102000).
文摘In this work,a new structure is used to enhance the nonlinear effect in the cavity,which improvesthe performance of the 1.3μm broadband swept source.The swept source adopts a semiconductoroptical amplifier(SOA),a circulator,a coupler,and a tunable filter.In the structure,the lightpasses through the nonlinear medium(SOA)twice in two opposite directions,which excites thenonlinear ffect and increases the performance of the swept source.The tunable filter is based on apolygon rotating mirror and gratings.Traditionally,multiple SOAs are adopted to improve thesweep range and the optical power,which increases the cost and complexity of the swept source.The method proposed in this paper can improve the spectral range and optical power of the sweptsources without additional accessories.For the short-cavity swept source,the power increasesfrom 6 mW to 7.7 mW,and the sweep range increases from 98 nm to 120 nm.The broadband swept sources could have wide applications in biomedical imaging,sensor system,measurementand so on.
基金National Natural Science Foundation of China(NSFC)(61327004,61377037,61378028,61378090,61421002,61435003,61505036)
文摘In this work, we investigate the methods to improve the performance of the swept source at 1.0 μm based on a polygon scanner, including in-cavity parameters and booster structures out of the cavity. The three in-cavity parameters are the cavity length, the rotating speed of the polygon scanner, and the in-cavity energy. With the decrease of cavity length, the spectrum bandwidth becomes wider and the duty cycle becomes higher.With the increase of the rotating speed of the polygon, the spectrum bandwidth becomes narrower, and the duty cycle becomes lower but the repetition rate becomes higher. With more energy in-cavity, the spectrum bandwidth becomes wider and the duty cycle becomes higher. The booster structures include the buffered structure, secondary amplifier, and dual-semiconductor optical amplifier configuration, which are used to increase the sweep frequency to 86 kHz, the output power to 18 mW, and the tuning bandwidth to 131 nm, respectively.
基金supported in part by the National Institutes of Health(R01EY024158 and R01EY028753)WRF David and Nancy Auth Innovation Awardan unrestricted fund from Research to Prevent Blindness.
文摘Background:There are two forms of system implementation of optical coherence tomography angiography(OCTA)in ophthalmic imaging,i.e.,spectral domain(SD-)and swept source OCTA(SS-OCTA).The purpose of this paper is to compare the SD-OCTA and SS-OCTA for elucidating structural and vascular features associated with central serous retinopathy(CSR),and to evaluate the effects of CSR on SD-and SS-OCTA’s imaging capabilities.Methods:Normal subjects and CSR patients were imaged by SD-and SS-OCTA using 3×3 mm and 6×6 mm scan patterns.OCT signal strengths at the superficial retina,deep retina,Sattler’s layer and Haller’s layer were used to compare the ability of SD-and SS-OCTA to image structural features.In addition,the ability to acquire angiograms were discussed by evaluating retinal vessel density.Central serous volume(CSV)was measured and it was correlated with difference in signal strengths(ΔS)between two OCTA devices.Results:Seven normal eyes and seven diseased eyes were recruited.Results showed no significant differences between SD-and SS-OCT in detecting structural features of the retinal layer according to the paired t-test.However,when imaging the Sattler’s layer for normal eyes,a significant difference is found between SD-and SS-OCT(p<0.0001 for 3×3 mm scan,and p=0.0002 for 6×6 mm);while for CSR eyes,the corresponding values were p<0.0001 and p=0.0003,respectively.At Haller’s layer for normal eyes,the corresponding values were p=0.0004 and p=0.0014;and for CSR eyes,p=0.0004 and p<0.0001,respectively.A strong correlation betweenΔS and CSV was observed in the Sattler’s layer(3×3 mm–p=0.0031 and R^(2)=0.951;6×6 mm–p=0.0075 and R^(2)=0.911)and Haller’s layer(3×3 mm–p=0.0026 and R^(2)=0.955;6×6 mm–p=0.0013 and R^(2)=0.972).Conclusions:The results suggest no differences between SD-and SS-OCTA for imaging the retinal layers however,when imaging beyond retinal layers,SS-OCTA appears advantageous in detecting returning signals.In CSR cases,the CSV may have an impact on sub-CSR tissue imaging and appears to have more impact on SD-than SS-OCTA.
基金supported by Natural Science Foundation of China(60978037,60878057).
文摘A novel broad tunable bandwidth and narrow instantaneous line-width linear swept laser source using combined tunable filters working at 1,300 nm center wavelength is proposed.The combined filters consist of a fiber FabryPerot tunable filter and a tunable filter based on diffractive grating with scanning polygon mirror.In contrast to traditional method using single tunable filter,the trade-off between bandwidth and instantaneous line-width is alleviated.Parallel implementation of two semiconductor optical amplifiers with different wavelength range is adopted in the laser resonator for broadband light amplification.The Fourier domain mode locking swept laser source with combined tunable filters offers broadband tunable range with narrow instantaneous line-width,which is especially benefiting for high-quality optical frequency domain imaging.The proposed Fourier domain mode locking swept laser source provides a tuning range of 160 nm with instantaneous line-width of about 0.01nm at sweeping rate of 15 kHz,a finesse of 16,000 is thus achieved.
文摘AIM: To compare the ocular fundus features of highly myopic eyes with and without macular Bruch’s membrane(BM) defects and investigate the associations between macular BM defects and other myopic lesions.METHODS: This retrospective, observational case series included 262 eyes(139 patients) with high myopia(HM) refractive error ≥-6.0 diopters(D) or axial length ≥26.5 mm from March 2019 to December 2019.The patients underwent a comprehensive ophthalmic examination, including sweptsource optical coherence tomography(SS-OCT).The features of macular BM defects and other ocular fundus lesions were examined in OCT images.RESULTS: Totally 51 eyes(19.5%) were detected with macular BM defects, which were characterized by a lack of BM, retinal pigment epithelium(RPE), and an almost complete loss of photoreceptors or choriocapillaris.Eyes with macular BM defects had worse best-corrected visual acuity(BCVA) than those without(P<0.001).Dome-shaped macula(DSM, P=0.042), retinal cysts(P=0.006), choroidal neovascularization(CNV, P<0.001), choroidal defects and abnormality(P=0.003), scleral defects(P=0.015), scleral deformation(P=0.005), posterior staphyloma(P=0.011), and perforating vessels(P<0.001) occurred more frequently in eyes with macular BM defects.In multivariate analysis, the presence of macular BM defects remained the significant association with presence of DSM(P=0.013), scleral defects(P=0.015), posterior staphyloma(P=0.001), perforating vessels(P<0.001) and CNV(P=0.004).CONCLUSION: Macular BM defects has a prevalence of approximately 20% in HM and it has tight association with other myopic fundus lesions.BM might be crucial in the pathogenesis of myopic fundus lesions due to its biomechanical function.A comprehensive understanding of BM’s role is useful for further researches about myopic lesions.
基金This work was supported in part by the Foundation of Wenzhou City Science&Technology Bureau(Y20180174)Medical and Health Science and Technology Program of Zhejiang Province(2019KY111)+3 种基金Zhejiang Provincial Key Research and Development Program(2018C03012)Zhejiang Provincial High-level Talents Program(2017-102)The funders had no role in the study design,data collection and analysis,decision to publish,or preparation of the manuscriptThe contribution of G.B.Bietti Foundation IRCCS was supported by the Italian Ministry of Health and Fondazione Roma.
文摘Background:To evaluate the effect of orthokeratology on precision of measurements in children using a new swept-source optical coherence tomography(SS-OCT)optical biometer(OA-2000),and agreement between its measurements and those provided by the commonly used IOLMaster based on partial coherence interferometry(PCI).Methods:This study recruited fifty-one eyes of 51 normal children(8–16 years).An operator took measurements with the two biometers.Then,a second operator took measurements with the SS-OCT biometer.After orthokeratology was performed for one month,the same operators repeated the same procedures.Axial length(AL),mean keratometry(Km)at 2.5 mm and 3.0 mm diameters(Km2.5 and Km3.0),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT)and corneal diameter(CD)were analyzed.Results:With the SS-OCT optical biometer,the test-retest repeatability of AL measurements was<0.06 mm.For all parameters,the coefficients of variation were<1.23%and the intraclass correlation coefficients were>0.95.The 95%limits of agreement of difference between the two devices for CD parameter were up to 1.53 mm.After orthokeratology,the fluctuation ranges of difference for Km3.0 measurement was 1.11 times higher than before orthokeratology,while the absolute values of difference for AL,Km2.5,ACD and CD measurements were comparable.Conclusions:Before and after orthokeratology,the SS-OCT biometer showed high repeatability and reproducibility for all measurements.Wearing orthokeratology contact lenses affected the agreement between SS-OCT and PCI biometers for Km3.0 measurements.The CD measurement showed poor agreement between the two devices.
基金The study was funded by Science and Technology Program of Guangzhou,China(201803010066)the National Natural Science Foundation of China(82000890)Young Talents’Science and Technology Innovation Project of Hainan Association for Science and Technology(QCXM202020).
文摘Background:To measure the anterior and posterior segment structural features of acute primary angle-closure(APAC)eyes.Methods:A total of 36 subjects with unilateral APAC were recruited in this study.The ocular biometric characteristics were measured by anterior segment optical coherence tomography(AS-OCT)and swept source optical coherence tomography(SS-OCT),respectively at baseline,2 weeks,and 1 month after surgical intervention.Results:At baseline,when compared with the fellow eyes,APAC-affected eyes showed significantly greater corneal thickness(P=0.004),shallower anterior chamber depth(ACD)(P<0.001),smaller anterior chamber area(ACA)(P=0.013),angle opening distance at 750μm from the scleral spur(AOD750)(P=0.002),trabecular-iris space area at 750μm from the scleral spur(TISA750)(P=0.033),angle recess area(ARA)(P=0.014),and iris area(IARE)(P=0.003),less iris curvature(ICURVE)(P=0.003),and larger lens vault(LV)(P=0.030).After intervention,the corneal thickness was significantly decreased at 1 month(P<0.001),while ACD,ACA,and AOD750 were significantly increased at 2 weeks and 1 month(all P<0.017).Changes in ACD were correlated with decreasing LV(P<0.05).The posterior segment parameters did not change over the 4-week period.Conclusions:When compared with the fellow eyes,APAC-affected eyes had greater corneal thickness,shallower anterior chamber,narrower angle,less ICURVE,and larger LV.After intervention,the corneal thickness was decreased,while the shallower anterior chamber was relieved to some extent.
基金supported by the Construction Project of High-Level Hospitals in Guangdong Province(303020107,303010303058)the National Natural Science Foundation of China(82271092,82401282)+1 种基金Guangdong Basic and Applied Research Foundation(2023A1515010430)Guangzhou Municipal Science and Technology Key Project(2024A03J0171).
文摘Aims:This study describes vascular abnormalities in X-linked retinoschisis(XLRS)using fundus fluorescein angiography(FFA)and ultra-widefield swept-source optical coherence tomography angiography(UWF SS-OCTA)to better understand the disease's vascular features and impact.Methods:A retrospective cross-sectional study was conducted on 26 XLRS patients(46 eyes).A comprehensive ophthalmic examination was performed,including FFA and UWF SS-OCTA.FFA abnormalities were divided into peripheral schisis-associated and optic disc-associated types.Results:The mean age of patients was 11.3±6.5 years.Macular schisis appeared in 97.8%of eyes,peripheral schisis in 89.1%,and peripheral bullous schisis(PBS)in 67.39%.Major vascular changes identified by FFA included dendritic capillary dilation/leakage(91.3%),internal residual vessel leakage(78.3%),and capillary dropout/ischemia(71.7%).Minor changes included zonal retinal pigment epithelium(RPE)proliferation(6.5%),bridging vessels(4.4%),and capillary sheathing(4.4%).peripapillary choroidal neovascularization(PPCNV)was noted in 10.9%and situs inversus of optic disc in 13.0%of eyes.Additionally,situs in versus of optic disc and zonal RPE proliferation were novel findings.Major FFA changes correlated with broader PBS(P=0.045)(P<0.001)(P=0.003).Clock hours of PBS were significant predictors for internal residual vessel leakage(OR=0.30,P=0.03).No significant correlation was found between gene mutation type and FFA abnormalities(P=0.539).Conclusions:This study highlighted the significant prevalence(95.7%)of vascular abnormalities in XLRS and emphasized the importance of combining FFA with UWF SS-OCTA for comprehensive evaluation,enhancing the understanding of XLRS pathophysiology and aiding in targeted treatment approaches.
基金supported in part by the Shenzhen Key Project for Technology Development(Nos.JSGG2020110215360002,JSGG20191129105838333,and CJGJZD20200617103003009).
文摘Swept source optical coherence tomography(SS-OCT)is a new noninvasive technique for assessing tissue.Although it hasadvantages,such as being label-free,noninvasive,and with high resolution,it also has drawbacks:there has been no indepth research into identifying the driving of swept source.Based on preliminary research,we demonstrate a novel drivingmodulation method of a fiber Fabry–Perot tunable filter ranging phase adjustable as a tool for making bandwidth compensation of a swept laser source.This novel method is analyzed in detail;a swept laser source with a sweep rate of100.5 kHz over a range of 152.25 nm and at a center wavelength of 1335.45 nm is demonstrated.
文摘The depth ranges of typical implementations of Fourier domain optical coherence tomography （FDOCT）, including spectral domain OCT （SDOCT） and swept source OCT （SSOCT）, are limited to several millimeters. To extend the depth range of current OCT systems, two novel systems with ultralong depth range were developed in this study. One is the orthogonal dispersive SDOCT （OD-SDOCT）, and the other is the recirculated swept source （R-SS） interferometer/OCT. No compromise between depth range and depth resolution is required in both systems. The developed OD-SDOCT system realized the longest depth range （over 100 mm） ever achieved by SDOCT, which is ready to be modified for depth-encoded parallel imaging on multiple sites. The developed R-SS interferometer achieved submicron precision within a depth range of 30mm, holding potential in real-time contact-free on-axis metrology of complex optical sys- tems.
