AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with catarac...AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with cataract.METHODS:This prospective case series was conducted at Tianjin Medical University Eye Hospital.In total,212 eyes from 212 patients scheduled for phacoemulsification were included.Eyes were evaluated preoperatively using two SSOCT devices(IOLMaster700 and CASIA2)and Scheimpflug tomography(Pentacam).Central corneal thickness(CCT),anterior chamber depth(ACD),aqueous depth(AQD),white-to-white distance(WTW),flat simulated keratometry(Kf),steep simulated keratometry(Ks),mean keratometry(Km),and total corneal keratometry(TKm)were measured.Intraclass correlation coefficient(ICC),95%confidence intervals(CI)and limits of agreement(LoA)widths were conducted to assess differences and correlations between devices.RESULTS:All parameters,except for Ks,were significantly different.Pairwise comparison revealed no significant differences between keratometry obtained by IOLMaster 700 and Pentacam.LoA widths of all paired comparisons for Ks were>0.80 D.Except for WTW between IOLMaster 700 and CASIA2 and between CASIA2 and Pentacam,other Pearson’s coefficients between devices showed a strong correlation(all r>0.95).The ICC of WTW(ICC=0.438,95%CI 0.167-0.625)showed poor reliability.The reliability of CCT,ACD,and AQD was excellent(all ICC>0.95),whereas that of TKm was good(ICC=0.827,95%CI 0.221-0.939).A significant linear correlation was also observed among devices.CONCLUSION:The ocular parameters derived from the use of IOLMaster700,CASIA2,and Pentacam exhibit significant discrepancies;as such,measurements from these devices should not be deemed as interchangeable.展开更多
Background:To compare two swept-source optical coherence tomography(SS-OCT)biometers,IOLMaster 700 and ANTERION.Methods:This is a retrospective study.Biometric measurements of cataract patients performed between March...Background:To compare two swept-source optical coherence tomography(SS-OCT)biometers,IOLMaster 700 and ANTERION.Methods:This is a retrospective study.Biometric measurements of cataract patients performed between March and July 2021 in the Department of Ophthalmology,United Christian Hospital,Hong Kong,were reviewed.Patients scheduled for cataract surgery were measured with both SS-OCT devices on the same day.The following biometry parameters were compared:keratometry(K),total keratometry(TK),axial length(AL),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT),white-to-white(WTW)and the predicted intraocular lens(IOL)power to achieve emmetropia.To assess the agreement between the devices,Bland-Altman analysis with 95%limits of agreement(LoA)were used.Results:In total,92 eyes of 47 subjects were measured with both devices.There were statistically significant differences between the two biometers for most measurements(P<0.05)except for flat K,AL and IOL power when using the right eyes for analysis.For the left eyes,there were statistically significant differences in the measurements from the two biometers in all parameters except for flat and steep K.The ANTERION did not obtain ACD,AL and LT in 2(2.17%),1(1.09%)and 5 cases(5.43%)respectively.Conclusions:The two biometers showed a clinically acceptable agreement in most parameters.Comparisons showed significant differences in most parameters but not clinically relevant except for the TK and WTW,and these two parameters should not be used interchangeably between the devices.展开更多
AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation usin...AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation using swept-source optical coherence tomography(SS-OCT).METHODS:We examined the right eyes of 116 patients with high myopia who were candidates for FS-LASIK surgery and ICL implantation.Sixty eyes underwent ICL V4c implantation and 56 eyes were subjected to FS-LASIK surgery.The CT was measured with SS-OCT.All data were recorded preoperatively and 2 h,1 wk,1 and 3 mo postoperatively.Other demographic information was collected,including age,sex,uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),spherical equivalent(SE),intraocular pressure(IOP)and axial length(AL).RESULTS:The UCVA improved in both groups and showed no significant differences between groups.There also were no significant differences between the two groups in postoperative BCVA and SE(P=0.581 and 0.203,respectively).The foveal CTs,inner nasal and outer nasal CTs were significantly thicker at 2 h postoperatively in both groups(P<0.05)but returned to baseline levels in 1 wk;after 1 mo,no significant differences were found relative to the preoperative values.At 3 mo in each group,nine regions showed variations in the CT as compared with preoperative thickening,but only the foveal and nasal area CTs preoperative differences were statistically significant(P<0.05).In addition,there was no significant difference in 9 regions of CT between the two groups at all follow-up times(P>0.05).CONCLUSION:The CTs after ICL implantation and FSLASIK surgery are significantly thicker than those before operation,especially in the foveal and nasal areas,but there is no significant difference between the two methods.展开更多
AIM:To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography(SS-OCT).METHODS:According to the body mass...AIM:To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography(SS-OCT).METHODS:According to the body mass index(BMI)results,the adults enrolled in the cross-sectional study were divided into the normal group(18.50≤BMI<25.00 kg/m^(2)),the overweight group(25.00≤BMI<30.00 kg/m^(2)),and the obesity group(BMI≥30.00 kg/m^(2)).The one-way ANOVA and the Chi-square test were used for comparisons.Pearson’s correlation analysis was used to evaluate the relationships between the measured variables.RESULTS:This research covered the left eyes of 3 groups of 434 age-and sex-matched subjects each:normal,overweight,and obesity.The mean BMI was 22.20±1.67,26.82±1.38,and 32.21±2.35 kg/m^(2) in normal,overweight and obesity groups,respectively.The choroid was significantly thinner in both the overweight and obesity groups compared to the normal group(P<0.05 for all),while the retinal thickness of the three groups did not differ significantly.Pearson’s correlation analysis showed that BMI was significantly negatively correlated with choroidal thickness,but no significant correlation was observed between BMI and retinal thickness.CONCLUSION:Choroidal thickness is decreased in people with overweight or obesity.Research on changes in choroidal thickness contributes to the understanding of the mechanisms of certain ocular disorders in overweight and obese adults.展开更多
AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of...AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.展开更多
AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Dem...AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.展开更多
A swept-source optical coherence tomography(SSOCT)system based on a high-speed scanning laser source at center wavelength of 1320 nm and scanning rate of 20 kHz is developed.The axial resolution is enhanced to 8.3μm ...A swept-source optical coherence tomography(SSOCT)system based on a high-speed scanning laser source at center wavelength of 1320 nm and scanning rate of 20 kHz is developed.The axial resolution is enhanced to 8.3μm by reshaping the spectrum in frequency domain using a window function and a wave number calibration method based on a Mach-Zender Interferometer(MZI)integrated in the SSOCT system.The imaging speed and depth range are 0.04 s per frame and 3.9 mm,respectively.The peak sensitivity of the SSOCT system is calibrated to be 112 dB.With the developed SSOCT system,optical coherence tomography(OCT)images of human finger tissue are obtained which enable us to view the sweat duct(SD),stratum corneum(SC)and epidermis(ED),demonstrating the feasibility of the SSOCT system for in vivo biomedical imaging.展开更多
AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were includ...AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were included who underwent uneventful phacoemulsification with IOL implantation in the Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan, China from February 2007 to January 2009. Preoperative AL and keratometric values (Ks) were measured by IOLMaster optical biometry. Patients were divided into 3 groups based on AL less than 22mm (Group 1), 22-26mm (Group 2), and more than 26mm (Group 3). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: the Haigis, Hoffer Q, Holladay 1, and SRK/T. The predictive accuracy of each formula was analyzed by comparing the difference between the actual and predicted postoperative SE (MedAE, median absolute error). All the patients had follow-up periods exceeding 3 months. RESULTS: Totally, there were 200 eyes (33 eyes in Group 1, 92 eyes in Group 2, 75 eyes in Group 3). In all patients, the Haigis had the significantly lower MedAE generated by the other formulas (P【0.05). In Group 1 to 3, the MedAE calculated by the Haigis was either significantly lower or comparable to those calculated by the other formulas.CONCLUSION: Compared with other formulas using IOLMaster biometric data, the Haigis formula yields superior refractive results in eyes with various AL.展开更多
Optical coherence tomography (OCT) is a relatively new imaging technology which can produce high resolution images of three-dimensional structures. OCT has been mainly used for medical applications such as for ophthal...Optical coherence tomography (OCT) is a relatively new imaging technology which can produce high resolution images of three-dimensional structures. OCT has been mainly used for medical applications such as for ophthalmology and dermatology. In this study we demonstrate its capability in providing much more reliable biometry identification of fingerprints than conventional methods. We prove that OCT can serve secure control of genuine fingerprints as it can detect if extra layers are placed above the finger. This can prevent with a high probability, intruders to a secure area trying to foul standard systems based on imaging the finger surface. En-Face OCT method is employed and recommended for its capability of providing not only the axial succession of layers in depth, but the en-face image that allows the traditional pattern identification. Another reason for using such OCT technology is that it is compatible with dynamic focus and therefore can provide enhanced transversal resolution and sensitivity. Two En-Face OCT systems are used to evaluate the need for high resolution and conclusions are drawn in terms of the most potential commercial route to ex- ploitation.展开更多
AIM: To analyse the impact of ultrasound and optical intraocular lens(IOL) calculation methods on refractive outcomes of cataract phacoemulsification performed after penetrating keratoplasty(PK) in keratoconus. METHOD...AIM: To analyse the impact of ultrasound and optical intraocular lens(IOL) calculation methods on refractive outcomes of cataract phacoemulsification performed after penetrating keratoplasty(PK) in keratoconus. METHODS: Phacoemulsification cataract surgery was performed on 42 eyes of 34 patients with keratoconus who had previously undergone PK. The IOL power was determined by using both standard and corneal topography-derived keratometry using the SRK/T formula. We used two independent methods-ultrasound biometry(UB) and interferometry [optical biometry(OB)] for IOL calculation. The analysed data from medical records included demographics, medical history, best corrected visual acuity(BCVA) on Snellen charts, technique of IOL calculation and calculation formula and its impact on final refractive result.RESULTS: BCVA ranged from 0.01 to 0.4(mean 0.09±0.19) before surgery and ranged from 0.2 to 0.7(mean 0.38±0.14) at 1 mo and from 0.2 to 1.0(mean 0.56±0.16)(P<0.05) at 3 mo, postoperatively. The refractive aim differed significantly from the refractive outcome in both the UB and OB groups(P<0.05). There was no statistically significant difference in the accuracy of the two biometry methods.CONCLUSION: The refractive aim in keratoconus eyes post-PK is not achieved with either ultrasound or OB.展开更多
Visualizing blood flow velocity distribution is essential for comprehending the pathogenesis of various diseases and facilitating early diagnosis and treatment.Current hemodynamic studies utilizing optical coherence t...Visualizing blood flow velocity distribution is essential for comprehending the pathogenesis of various diseases and facilitating early diagnosis and treatment.Current hemodynamic studies utilizing optical coherence tomography(OCT)primarily rely on Doppler OCT(D-OCT)and OCT Angiography(OCTA),which measure axial blood vessel velocity or visualize the vascular architecture,respectively.However,these techniques have limitations in accurately quantifying the absolute velocity of red blood cells(RBCs).This study presents a novel method based on microsphere tracking,which enables precise quantification of absolute blood flow velocity along a blood vessel.In phantom experiments,freshly harvested blood mixed with microspheres was infused into a cellulose tube to simulate a single blood vessel.Experimental results,demon-strating an error margin of less than 10%,validated the effectiveness of this method.Blood flow velocities ranging from 0.472 mm/s to 18.9 mm/s were accurately measured.A preliminary in vivo examination of rabbit ear vessels was conducted,further validating the reliability of this method.This study presents a potential method for specific disease diagnosis by detecting tar-geted vessel flow velocity variations using swept-source optical coherence tomography(SS-OCT)combined with microsphere tracking.展开更多
AIM:To assess the inter-device consistency of corneal curvature and central corneal thickness between Pentacam and a swept-source Fourier-domain anterior segment optical coherence tomography(AS-OCT)in ectopia lentis p...AIM:To assess the inter-device consistency of corneal curvature and central corneal thickness between Pentacam and a swept-source Fourier-domain anterior segment optical coherence tomography(AS-OCT)in ectopia lentis patients.METHODS:Totally 72 eyes of ectopia lentis patients were recruited.Central corneal thickness(CCT),corneal curvature values and corneal astigmatism were obtained from both the Pentacam and AS-OCT(CASIA2).Repeatability was evaluated for both devices.The coef ficient of repeatability(COR)and the relative COR was calculated.Bland-Altman plots were conducted to evaluate the interdevice agreement of measurement.Orthogonal linear regression was used to examine any proportional bias.RESULTS:The mean difference of CCT,steep anterior corneal cur vature(anterior K_S),flat anterior corneal curvature(anterior K_f),anterior corneal astigmatism(ACA),steep posterior corneal cur vature(posterior K_S),flat posterior corneal cur vature(posterior K_f),posterior corneal astigmatism(PCA),steep true net power(TNP K_S),flat true net power(TNP K_f)and total corneal astigmatism(TCA)between Pentacam and CASIA2 were 7.03±9.70μm,-0.19±0.41 D,-0.27±0.35 D,0.04±0.47 D,-0.17±0.23 D,-0.11±0.11 D,-0.02±1.02 D-0.41±0.43 D,-0.52±0.46 D,and-0.15±0.96 D,respectively.For measurement of TNP K_f with the Pentacam and CASIA2,a mean difference of 0.52 D and COR of 0.90 with P=0.02 was detected.There was no significant difference in CCT(P=0.393),anterior K_f(P=0.107),anteriorKs(P=0.414),ACA(P=0.131),posterior K_f(P=0.286),posterior Ks(P=0.418),PCA(P=0.105),TNP Ks(P=0.054),and TCA(P=0.977)between Pentacam and CASIA2.CONCLUSION:Our study reveals good agreement of CCT,corneal curvature and corneal astigmatism measured by CASIA2 and Pentacam in ectopia lentis patients.However,there was significant difference for CCT and corneal curvature values obtained by the two devices.展开更多
AIM: To compare ultra-widefield(24×20 mm^(2)) sweptsource optical coherence tomography angiography(SSOCTA) and fluorescein angiography(FA) in the evaluation of diabetic retinopathy(DR) lesions. METHODS: Forty-six...AIM: To compare ultra-widefield(24×20 mm^(2)) sweptsource optical coherence tomography angiography(SSOCTA) and fluorescein angiography(FA) in the evaluation of diabetic retinopathy(DR) lesions. METHODS: Forty-six eyes of 23 patients with treatmentna?ve DR were included at Peking University People’s Hospital from September 1, 2021, until December 31, 2021, as well as 23 age and gender matched healthy controls. Quantitative assessments of DR lesions on FA and SS-OCTA(superficial capillary plexus, SCP, 24×20 mm^(2)) were performed.RESULTS: Area of fovea avascular zone(FAZ) was larger in DR cases than controls(0.34±0.069 mm^(2) vs 0.287±0.108 mm^(2), P=0.006). In DR eyes, the mean FAZ area was 0.34±0.069 and 0.334±0.087 mm^(2) on SS-OCTA and FA, respectively(P=0.428), while the median FAZ perimeter was 2.382(IQR, 2.201-2.59) and 2.333(IQR, 2.138-2.6) mm on SS-OCTA and FA images(P=0.733). There was no significant difference in the size of the non-perfusion area(NPA) between the images on SS-OCTA and FA(12.389, IQR 4.96-28.3 and 11.125, IQR 5-28.31 mm^(2), P=0.197). The median total microaneurysm(MA) count was 35(IQR, 19-46) and 73(IQR, 43-93) on SS-OCTA and FA(P<0.001), respectively. No significant difference in intra-retinal microvascular abnormality(IRMA) and neovascularization (NV) count was found between the two techniques. The intraclass coefficient(ICCs) of all the parameters above indicated stable repeatability.CONCLUSION: Ultra-widefield SS-OCTA represents a reliable, noninvasive, and quantitative imaging technique in the assessment of microvasculature in DR, which offers a potential substitute for FA in DR evaluation.展开更多
Objective: To compare refractive outcomes using the Lenstar optical low-coherence reflectometry (OLCR) biometer in the following cases: phacovitrectomy for epiretinal membranes and macular holes (phacovitrectomy group...Objective: To compare refractive outcomes using the Lenstar optical low-coherence reflectometry (OLCR) biometer in the following cases: phacovitrectomy for epiretinal membranes and macular holes (phacovitrectomy group);sequential cataract surgery after prior vitrectomy (sequential-phaco group);routine cataract surgery (phaco-only group). Methods: This study was a retrospective, consecutive comparative series. Main outcomes were mean prediction error (ME) and mean absolute prediction error (MAE). Secondary out-come was the variance in prediction error. Results: ME was significantly more myopic in the phacovitrectomy group (-0.08 ± 0.77D, mean ± SD, p = 0.04) and the sequentialphaco group (-0.09 ± 0.51D, p = 0.01) compared to the phaco-only group (+0.24 ± 0.53D). MAEs were not statistically different across the 3 groups. The phacovitrectomy group had a wider variance in prediction errors compared to the phaco-only group (p = 0.03). Conclusions: There is a myopic shift of approximately -0.3D in both phacovitrectomy and sequential-phaco cases compared to phaco-only cases when using OLCR-based optical biometry. Phacovitrectomy outcomes are more variable compared to phaco-only eyes.展开更多
AIM:To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens(IOL)implantation,based on anterior segment swept-source optical co...AIM:To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens(IOL)implantation,based on anterior segment swept-source optical coherence tomography(AS-SS-OCT)measurements.METHODS:This was a prospective case control study;sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure(IOP).Based on anterior chamber depth(ACD)and gonioscopy findings,the eyes were divided into two groups:group of shallow anterior chamber and narrow angle(SAC group,30 eyes);and group of normal anterior chamber group with wide angle(NAC group,30 eyes).Measurements of ACD,anterior chamber volume(ACV),iris volume(IV),lens vault(LV),angle opening distance(AOD),angle recess area(ARA),trabecular iris space area(TISA),and trabecular iris angle(TIA)were conducted in each group before and 3mo after surgery.RESULTS:There was no significant difference in age,axial length(AL),corneal curvature,corneal diameter,intraocular pressure,and IV between two groups before surgery,except for the LV(P=0.000).ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation(3.69±0.38 vs 3.85±0.39 mm,P=0.025;161.37±19.47 vs 178.26±20.30 mm3,P=0.002).AOD750,ARA750 in nasal and inferior quadrants,TISA750 in all quadrants except temporal,and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation(all P<0.05).CONCLUSION:Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects,but the angle related parameters including AOD750,ARA750,TISA750,TIA,TISA750,and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level.展开更多
AIM:To determine the agreement of ocular biometric indices including axial length,keratometric readings,anterior chamber depth,and horizontal corneal diameter between the Pentacam AXL and IOL Master 500.METHODS:The st...AIM:To determine the agreement of ocular biometric indices including axial length,keratometric readings,anterior chamber depth,and horizontal corneal diameter between the Pentacam AXL and IOL Master 500.METHODS:The study was a large cross-sectional population-based study(Tehran Geriatric Eye Study)conducted from Jan 2019 to Jan 2020.A total of 160 clusters were randomly selected proportional to size(each cluster contained 20 individuals)from 22 strata of Tehran city.All people aged 60y and above were invited to participate in the study.For all participants,preliminary ocular examinations were performed including the measurement of uncorrected and best-corrected visual acuity,objective and subjective refraction,anterior and posterior segment examinations.All participants underwent an ocular biometry using the Pentacam AXL and IOL Master 500.RESULTS:The 95%limits of agreement(LoA)between the two devices were-0.13 to 0.19,-0.15 to 0.17,and-0.13 to 0.19 in normal,pseudophakic,and cataractous eyes,respectively.With increasing the axial length,the difference between the two devices significantly increased in all three groups of normal,pseudophakic,and cataractous eyes(P<0.001).The 95% LoAs between the two devices regarding the mean keratometry shows that the best LoAs were seen in cataractous(-0.33 to 0.81)and followed by normal eyes(-0.36 to 0.86)and the pseudophakic eyes(-0.48 to 0.90)had the widest LoA.The 95% LoAs for horizontal corneal diameter measurements were-0.08 to 0.86,-0.03 to 0.83,and-0.07 to 0.87 in normal,pseudophakic,and cataractous eyes,respectively.The 95% LoAs of anterior chamber depth measurements between the two devices was-0.39 to 0.19 and-0.37 to 0.13 in normal eyes and cataractous,respectively.CONCLUSION:The Pentacam AXL has excellent agreement with the gold standard,IOL Master 500 in measuring axial length.In eyes with cataracts,the difference between the two devices is more scattered.With the increasing of axial length,the difference between the two devices increased,which should be considered when using Pentacam AXL.展开更多
·AIM:To describe the morphological characteristics of foveal avascular zone(FAZ)in normal Chinese adults with or without myopia by swept-source optical coherence tomography angiography(SS-OCTA)and analyze the pos...·AIM:To describe the morphological characteristics of foveal avascular zone(FAZ)in normal Chinese adults with or without myopia by swept-source optical coherence tomography angiography(SS-OCTA)and analyze the possible associated factors.·METHODS:Normal Chinese adults with or without myopia aged between 18 and 60 y were recruited into the study.One eye in each individual was randomly selected for scanning using SS-OCTA.FAZ parameters,central retinal thickness(CRT)and central choroidal thickness(CCT)were then analyzed.Correlations between systemic and ocular variables and FAZ parameters were subsequently evaluated.The subgroup analysis based on refractive error was also carried out.·RESULTS:In total,127 eyes out of 127 normal subjects were finally included in the study(mean age29.5±8.22 y,61 males and 66 females).The pattern of FAZ was variable:round configuration in 28 eyes(22%),quadrilateral configuration in 23 eyes(18%),pentagonal configuration in 20 eyes(16%),oval configuration in 15 eyes(12%),triangular configuration in 6 eyes(5%)and irregular configuration in 35 eyes(28%).The mean area of FAZ was0.37±0.12 mm^(2).Females had a larger FAZ(0.41±0.11 mm^(2)vs0.32±0.11 mm^(2))compared with that of males(P<0.01).All myopic individuals showed smaller FAZ area and perimeter compared with that of normal individuals(P<0.01).There was no obvious correlation between age and FAZ.In the univariate regression analysis,both axial length(AL)and refractive error were significantly related to FAZ parameters.However,only CRT showed negative correlation with FAZ in the multivariate regression analysis.·CONCLUSION:The pattern of FAZ configuration in normal Chinese adults with or without myopia is highly variable.Establishing quantitative parameters of FAZ would not only provide details of macular pathophysiology but could possibly contribute as a biomarker in disease staging.展开更多
AIMTo assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US).METHODSThere were 218 adult subjects (218 eyes) aged 59.2&...AIMTo assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US).METHODSThere were 218 adult subjects (218 eyes) aged 59.2±9.2y enrolled in this prospective cross-sectional study. Forty-three eyes had open angles and 175 eyes had narrow angles. Routine ophthalmic exam was performed and nuclear opacity was graded using the Lens Opacities Classification System III (LOCS III). Lens thickness was measured by AS-OCT (Visante OCT, Carl Zeiss Meditec, Dublin, CA, USA). The highest quality image was selected for each eye and lens thickness was calculated using ImageJ software. Lens thickness was also measured by A-scan US.RESULTSInterclass correlations showed a value of 99.7% for intra-visit measurements and 95.3% for inter-visit measurements. The mean lens thickness measured by AS-OCT was not significantly different from that of A-scan US (4.861±0.404 vs 4.866±0.351 mm, P=0.74). Lens thickness values obtained from the two instruments were highly correlated overall (Pearson correlation coefficient=0.81, P<0.001), and in all LOCS III specific subgroups except in grade 5 of nuclear opacity. Bland-Altman analysis revealed a 95% limit of agreement from -0.45 to 0.46 mm. Lens thickness difference between the two instruments became smaller as the lens thickness increased and AS-OCT yielded smaller values than A-scan US in thicker lens (β=-0.29, P<0.001)CONCLUSIONAS-OCT-derived lens thickness measurement is valid and comparable to the results obtained by A-scan US. It can be used as a reliable noncontact method for measuring lens thickness in adults with or without significant cataract.展开更多
In swept-source optical coherence tomography(SSOCT),the swept-source stimulates system by a series of wavelengths in time sequence;a photo detector then collects all reflected/backscattered light from testing sample a...In swept-source optical coherence tomography(SSOCT),the swept-source stimulates system by a series of wavelengths in time sequence;a photo detector then collects all reflected/backscattered light from testing sample as the components of Fourier series.Due to the nature of the SSOCT,the processing in spectral domain can merge multiple swept-sources with different central wavelengths,which greatly increases the resolution of the OCT imaging.In the wavelength probing OCT,a standard broadband SSOCT system is used to extract the internal structure of the sample,and another narrow band light can be used to probe the spectral feature of the sample at the probing wavelength.展开更多
AIM:To compare the dif ferences of choroidal neovascularization(CNV)measurements between sweptsource and spectral-domain optical coherence tomography angiography(SS-OCTA and SD-OCTA)in neovascular agerelated macular d...AIM:To compare the dif ferences of choroidal neovascularization(CNV)measurements between sweptsource and spectral-domain optical coherence tomography angiography(SS-OCTA and SD-OCTA)in neovascular agerelated macular degeneration(nAMD)and the imaging reliability of the two devices.METHODS:Prospective comparative study.SS-OCTA and SD-OCTA were used to scan the same eye with the modes of 3×3 and 6×6 mm2 centered on the neovascularization.Only qualified images were chosen and the border of CNV was manually delineated by two graders independently.The area of CNV(ACNV),vascular perfusion density(PD),and vessel length density(VLD)within the delineation were calculated using Image J.The differences of CNV measurements between the two OCTA devices were compared using Bland-Altman analysis.The agreement between the two graders on the measurements of each device was compared using the intraclass correlation coefficient(ICC).RESULTS:A total of 18 patients(22 eyes)with nAMD were included.The measurements of ACNV,PD,and VLD were 7.247±4.586 and 4.901±3.741 mm^(2),43.202±9.636 and 34.904±10.489,6.339±1.228 and 5.908±1.741 mm^(-1) for SS-OCTA and SD-OCTA,respectively.The differences between the two devices were 2.346±3.030 mm^(2)(Z=-3.782,P<0.0001),8.298±14.160(Z=-2.419,P=0.016),and 0.431±2.114 mm^(-1)(Z=-0.828,P=0.408)for ACNV,PD and VLD,respectively.The ICC between two graders were 0.893(P<0.001),0.902(P<0.001),0.885(P<0.001)for ACNV,PD,VLD in SS-OCTA,and 0.971(P<0.001),0.976(P<0.001),0.973(P<0.001)in SD-OCTA,respectively.CONCLUSION:Both OCTA devices have high imaging reliability.Compared with SD-OCTA,SS-OCTA has a larger ACNV measurements,but doesn’t show better resolution of internal vessels of CNV and well signal strength.展开更多
基金Supported by Tianjin Key Medical Discipline (Specialty) Construction Project (No.TJYXZDXK-037A)Weifang Science and Technology Bureau Project (No.2020YX065).
文摘AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with cataract.METHODS:This prospective case series was conducted at Tianjin Medical University Eye Hospital.In total,212 eyes from 212 patients scheduled for phacoemulsification were included.Eyes were evaluated preoperatively using two SSOCT devices(IOLMaster700 and CASIA2)and Scheimpflug tomography(Pentacam).Central corneal thickness(CCT),anterior chamber depth(ACD),aqueous depth(AQD),white-to-white distance(WTW),flat simulated keratometry(Kf),steep simulated keratometry(Ks),mean keratometry(Km),and total corneal keratometry(TKm)were measured.Intraclass correlation coefficient(ICC),95%confidence intervals(CI)and limits of agreement(LoA)widths were conducted to assess differences and correlations between devices.RESULTS:All parameters,except for Ks,were significantly different.Pairwise comparison revealed no significant differences between keratometry obtained by IOLMaster 700 and Pentacam.LoA widths of all paired comparisons for Ks were>0.80 D.Except for WTW between IOLMaster 700 and CASIA2 and between CASIA2 and Pentacam,other Pearson’s coefficients between devices showed a strong correlation(all r>0.95).The ICC of WTW(ICC=0.438,95%CI 0.167-0.625)showed poor reliability.The reliability of CCT,ACD,and AQD was excellent(all ICC>0.95),whereas that of TKm was good(ICC=0.827,95%CI 0.221-0.939).A significant linear correlation was also observed among devices.CONCLUSION:The ocular parameters derived from the use of IOLMaster700,CASIA2,and Pentacam exhibit significant discrepancies;as such,measurements from these devices should not be deemed as interchangeable.
文摘Background:To compare two swept-source optical coherence tomography(SS-OCT)biometers,IOLMaster 700 and ANTERION.Methods:This is a retrospective study.Biometric measurements of cataract patients performed between March and July 2021 in the Department of Ophthalmology,United Christian Hospital,Hong Kong,were reviewed.Patients scheduled for cataract surgery were measured with both SS-OCT devices on the same day.The following biometry parameters were compared:keratometry(K),total keratometry(TK),axial length(AL),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT),white-to-white(WTW)and the predicted intraocular lens(IOL)power to achieve emmetropia.To assess the agreement between the devices,Bland-Altman analysis with 95%limits of agreement(LoA)were used.Results:In total,92 eyes of 47 subjects were measured with both devices.There were statistically significant differences between the two biometers for most measurements(P<0.05)except for flat K,AL and IOL power when using the right eyes for analysis.For the left eyes,there were statistically significant differences in the measurements from the two biometers in all parameters except for flat and steep K.The ANTERION did not obtain ACD,AL and LT in 2(2.17%),1(1.09%)and 5 cases(5.43%)respectively.Conclusions:The two biometers showed a clinically acceptable agreement in most parameters.Comparisons showed significant differences in most parameters but not clinically relevant except for the TK and WTW,and these two parameters should not be used interchangeably between the devices.
基金Supported by the Cross-disciplinary Research Fund of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine(No.JYJC201907)。
文摘AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation using swept-source optical coherence tomography(SS-OCT).METHODS:We examined the right eyes of 116 patients with high myopia who were candidates for FS-LASIK surgery and ICL implantation.Sixty eyes underwent ICL V4c implantation and 56 eyes were subjected to FS-LASIK surgery.The CT was measured with SS-OCT.All data were recorded preoperatively and 2 h,1 wk,1 and 3 mo postoperatively.Other demographic information was collected,including age,sex,uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),spherical equivalent(SE),intraocular pressure(IOP)and axial length(AL).RESULTS:The UCVA improved in both groups and showed no significant differences between groups.There also were no significant differences between the two groups in postoperative BCVA and SE(P=0.581 and 0.203,respectively).The foveal CTs,inner nasal and outer nasal CTs were significantly thicker at 2 h postoperatively in both groups(P<0.05)but returned to baseline levels in 1 wk;after 1 mo,no significant differences were found relative to the preoperative values.At 3 mo in each group,nine regions showed variations in the CT as compared with preoperative thickening,but only the foveal and nasal area CTs preoperative differences were statistically significant(P<0.05).In addition,there was no significant difference in 9 regions of CT between the two groups at all follow-up times(P>0.05).CONCLUSION:The CTs after ICL implantation and FSLASIK surgery are significantly thicker than those before operation,especially in the foveal and nasal areas,but there is no significant difference between the two methods.
基金Supported by the Science and Technology Commission of Shanghai Municipality(No.20Y11910800).
文摘AIM:To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography(SS-OCT).METHODS:According to the body mass index(BMI)results,the adults enrolled in the cross-sectional study were divided into the normal group(18.50≤BMI<25.00 kg/m^(2)),the overweight group(25.00≤BMI<30.00 kg/m^(2)),and the obesity group(BMI≥30.00 kg/m^(2)).The one-way ANOVA and the Chi-square test were used for comparisons.Pearson’s correlation analysis was used to evaluate the relationships between the measured variables.RESULTS:This research covered the left eyes of 3 groups of 434 age-and sex-matched subjects each:normal,overweight,and obesity.The mean BMI was 22.20±1.67,26.82±1.38,and 32.21±2.35 kg/m^(2) in normal,overweight and obesity groups,respectively.The choroid was significantly thinner in both the overweight and obesity groups compared to the normal group(P<0.05 for all),while the retinal thickness of the three groups did not differ significantly.Pearson’s correlation analysis showed that BMI was significantly negatively correlated with choroidal thickness,but no significant correlation was observed between BMI and retinal thickness.CONCLUSION:Choroidal thickness is decreased in people with overweight or obesity.Research on changes in choroidal thickness contributes to the understanding of the mechanisms of certain ocular disorders in overweight and obese adults.
基金Supported by the National Natural Science Foundation of China(No.82101087)Shanghai Clinical Research Key Project(No.SHDC2020CR6029).
文摘AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.
基金OFTARED “RD16/0008/0010”,funded by Instituto de Salud Carlos Ⅲ,integrated in the national I+D+i 2013-2016co-funded by European Union(ERDF/ESF,“Investing in your future”)
文摘AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.
基金supported by the National High Technology Research and Development Program of China(2006AA02Z4E0,2008AA02Z422)Natural Science Foundation of China(60878057,60478040).
文摘A swept-source optical coherence tomography(SSOCT)system based on a high-speed scanning laser source at center wavelength of 1320 nm and scanning rate of 20 kHz is developed.The axial resolution is enhanced to 8.3μm by reshaping the spectrum in frequency domain using a window function and a wave number calibration method based on a Mach-Zender Interferometer(MZI)integrated in the SSOCT system.The imaging speed and depth range are 0.04 s per frame and 3.9 mm,respectively.The peak sensitivity of the SSOCT system is calibrated to be 112 dB.With the developed SSOCT system,optical coherence tomography(OCT)images of human finger tissue are obtained which enable us to view the sweat duct(SD),stratum corneum(SC)and epidermis(ED),demonstrating the feasibility of the SSOCT system for in vivo biomedical imaging.
基金supported by grants of Far Eastern Memorial Hospital (FEMH-97-HHC-008), Taiwan,China
文摘AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were included who underwent uneventful phacoemulsification with IOL implantation in the Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan, China from February 2007 to January 2009. Preoperative AL and keratometric values (Ks) were measured by IOLMaster optical biometry. Patients were divided into 3 groups based on AL less than 22mm (Group 1), 22-26mm (Group 2), and more than 26mm (Group 3). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: the Haigis, Hoffer Q, Holladay 1, and SRK/T. The predictive accuracy of each formula was analyzed by comparing the difference between the actual and predicted postoperative SE (MedAE, median absolute error). All the patients had follow-up periods exceeding 3 months. RESULTS: Totally, there were 200 eyes (33 eyes in Group 1, 92 eyes in Group 2, 75 eyes in Group 3). In all patients, the Haigis had the significantly lower MedAE generated by the other formulas (P【0.05). In Group 1 to 3, the MedAE calculated by the Haigis was either significantly lower or comparable to those calculated by the other formulas.CONCLUSION: Compared with other formulas using IOLMaster biometric data, the Haigis formula yields superior refractive results in eyes with various AL.
文摘Optical coherence tomography (OCT) is a relatively new imaging technology which can produce high resolution images of three-dimensional structures. OCT has been mainly used for medical applications such as for ophthalmology and dermatology. In this study we demonstrate its capability in providing much more reliable biometry identification of fingerprints than conventional methods. We prove that OCT can serve secure control of genuine fingerprints as it can detect if extra layers are placed above the finger. This can prevent with a high probability, intruders to a secure area trying to foul standard systems based on imaging the finger surface. En-Face OCT method is employed and recommended for its capability of providing not only the axial succession of layers in depth, but the en-face image that allows the traditional pattern identification. Another reason for using such OCT technology is that it is compatible with dynamic focus and therefore can provide enhanced transversal resolution and sensitivity. Two En-Face OCT systems are used to evaluate the need for high resolution and conclusions are drawn in terms of the most potential commercial route to ex- ploitation.
文摘AIM: To analyse the impact of ultrasound and optical intraocular lens(IOL) calculation methods on refractive outcomes of cataract phacoemulsification performed after penetrating keratoplasty(PK) in keratoconus. METHODS: Phacoemulsification cataract surgery was performed on 42 eyes of 34 patients with keratoconus who had previously undergone PK. The IOL power was determined by using both standard and corneal topography-derived keratometry using the SRK/T formula. We used two independent methods-ultrasound biometry(UB) and interferometry [optical biometry(OB)] for IOL calculation. The analysed data from medical records included demographics, medical history, best corrected visual acuity(BCVA) on Snellen charts, technique of IOL calculation and calculation formula and its impact on final refractive result.RESULTS: BCVA ranged from 0.01 to 0.4(mean 0.09±0.19) before surgery and ranged from 0.2 to 0.7(mean 0.38±0.14) at 1 mo and from 0.2 to 1.0(mean 0.56±0.16)(P<0.05) at 3 mo, postoperatively. The refractive aim differed significantly from the refractive outcome in both the UB and OB groups(P<0.05). There was no statistically significant difference in the accuracy of the two biometry methods.CONCLUSION: The refractive aim in keratoconus eyes post-PK is not achieved with either ultrasound or OB.
基金supported by the National Natural Science Foundation of China(62175156,81827807)the Science and Technology Commission of Shanghai Municipality(22S31903000)+3 种基金the Collaborative Innovation Project of Shanghai Institute of Technology(XTCX2022-27)the Shenzhen Basic Research Key Project(JCYJ20220818103212026)the Shenzhen Key Technology Project(JSGGZD20220822095200002)the Shenzhen Outstanding Scientific and Technological Innovation Talents Distinguished Young Scientists(RCJC20210609104443085).
文摘Visualizing blood flow velocity distribution is essential for comprehending the pathogenesis of various diseases and facilitating early diagnosis and treatment.Current hemodynamic studies utilizing optical coherence tomography(OCT)primarily rely on Doppler OCT(D-OCT)and OCT Angiography(OCTA),which measure axial blood vessel velocity or visualize the vascular architecture,respectively.However,these techniques have limitations in accurately quantifying the absolute velocity of red blood cells(RBCs).This study presents a novel method based on microsphere tracking,which enables precise quantification of absolute blood flow velocity along a blood vessel.In phantom experiments,freshly harvested blood mixed with microspheres was infused into a cellulose tube to simulate a single blood vessel.Experimental results,demon-strating an error margin of less than 10%,validated the effectiveness of this method.Blood flow velocities ranging from 0.472 mm/s to 18.9 mm/s were accurately measured.A preliminary in vivo examination of rabbit ear vessels was conducted,further validating the reliability of this method.This study presents a potential method for specific disease diagnosis by detecting tar-geted vessel flow velocity variations using swept-source optical coherence tomography(SS-OCT)combined with microsphere tracking.
基金Supported by National Natural Science Foundation of China(No.81873673,No.81900841)the Fundamental Research Funds of the State Key Laboratory of Ophthalmology(No.30306020240020212)the Young Teachers Training Program of Sun Yat-sen University(No.20ykpy143)。
文摘AIM:To assess the inter-device consistency of corneal curvature and central corneal thickness between Pentacam and a swept-source Fourier-domain anterior segment optical coherence tomography(AS-OCT)in ectopia lentis patients.METHODS:Totally 72 eyes of ectopia lentis patients were recruited.Central corneal thickness(CCT),corneal curvature values and corneal astigmatism were obtained from both the Pentacam and AS-OCT(CASIA2).Repeatability was evaluated for both devices.The coef ficient of repeatability(COR)and the relative COR was calculated.Bland-Altman plots were conducted to evaluate the interdevice agreement of measurement.Orthogonal linear regression was used to examine any proportional bias.RESULTS:The mean difference of CCT,steep anterior corneal cur vature(anterior K_S),flat anterior corneal curvature(anterior K_f),anterior corneal astigmatism(ACA),steep posterior corneal cur vature(posterior K_S),flat posterior corneal cur vature(posterior K_f),posterior corneal astigmatism(PCA),steep true net power(TNP K_S),flat true net power(TNP K_f)and total corneal astigmatism(TCA)between Pentacam and CASIA2 were 7.03±9.70μm,-0.19±0.41 D,-0.27±0.35 D,0.04±0.47 D,-0.17±0.23 D,-0.11±0.11 D,-0.02±1.02 D-0.41±0.43 D,-0.52±0.46 D,and-0.15±0.96 D,respectively.For measurement of TNP K_f with the Pentacam and CASIA2,a mean difference of 0.52 D and COR of 0.90 with P=0.02 was detected.There was no significant difference in CCT(P=0.393),anterior K_f(P=0.107),anteriorKs(P=0.414),ACA(P=0.131),posterior K_f(P=0.286),posterior Ks(P=0.418),PCA(P=0.105),TNP Ks(P=0.054),and TCA(P=0.977)between Pentacam and CASIA2.CONCLUSION:Our study reveals good agreement of CCT,corneal curvature and corneal astigmatism measured by CASIA2 and Pentacam in ectopia lentis patients.However,there was significant difference for CCT and corneal curvature values obtained by the two devices.
基金Supported by the National Key R&D Program of China (No.2020YFC2008200)。
文摘AIM: To compare ultra-widefield(24×20 mm^(2)) sweptsource optical coherence tomography angiography(SSOCTA) and fluorescein angiography(FA) in the evaluation of diabetic retinopathy(DR) lesions. METHODS: Forty-six eyes of 23 patients with treatmentna?ve DR were included at Peking University People’s Hospital from September 1, 2021, until December 31, 2021, as well as 23 age and gender matched healthy controls. Quantitative assessments of DR lesions on FA and SS-OCTA(superficial capillary plexus, SCP, 24×20 mm^(2)) were performed.RESULTS: Area of fovea avascular zone(FAZ) was larger in DR cases than controls(0.34±0.069 mm^(2) vs 0.287±0.108 mm^(2), P=0.006). In DR eyes, the mean FAZ area was 0.34±0.069 and 0.334±0.087 mm^(2) on SS-OCTA and FA, respectively(P=0.428), while the median FAZ perimeter was 2.382(IQR, 2.201-2.59) and 2.333(IQR, 2.138-2.6) mm on SS-OCTA and FA images(P=0.733). There was no significant difference in the size of the non-perfusion area(NPA) between the images on SS-OCTA and FA(12.389, IQR 4.96-28.3 and 11.125, IQR 5-28.31 mm^(2), P=0.197). The median total microaneurysm(MA) count was 35(IQR, 19-46) and 73(IQR, 43-93) on SS-OCTA and FA(P<0.001), respectively. No significant difference in intra-retinal microvascular abnormality(IRMA) and neovascularization (NV) count was found between the two techniques. The intraclass coefficient(ICCs) of all the parameters above indicated stable repeatability.CONCLUSION: Ultra-widefield SS-OCTA represents a reliable, noninvasive, and quantitative imaging technique in the assessment of microvasculature in DR, which offers a potential substitute for FA in DR evaluation.
文摘Objective: To compare refractive outcomes using the Lenstar optical low-coherence reflectometry (OLCR) biometer in the following cases: phacovitrectomy for epiretinal membranes and macular holes (phacovitrectomy group);sequential cataract surgery after prior vitrectomy (sequential-phaco group);routine cataract surgery (phaco-only group). Methods: This study was a retrospective, consecutive comparative series. Main outcomes were mean prediction error (ME) and mean absolute prediction error (MAE). Secondary out-come was the variance in prediction error. Results: ME was significantly more myopic in the phacovitrectomy group (-0.08 ± 0.77D, mean ± SD, p = 0.04) and the sequentialphaco group (-0.09 ± 0.51D, p = 0.01) compared to the phaco-only group (+0.24 ± 0.53D). MAEs were not statistically different across the 3 groups. The phacovitrectomy group had a wider variance in prediction errors compared to the phaco-only group (p = 0.03). Conclusions: There is a myopic shift of approximately -0.3D in both phacovitrectomy and sequential-phaco cases compared to phaco-only cases when using OLCR-based optical biometry. Phacovitrectomy outcomes are more variable compared to phaco-only eyes.
文摘AIM:To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens(IOL)implantation,based on anterior segment swept-source optical coherence tomography(AS-SS-OCT)measurements.METHODS:This was a prospective case control study;sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure(IOP).Based on anterior chamber depth(ACD)and gonioscopy findings,the eyes were divided into two groups:group of shallow anterior chamber and narrow angle(SAC group,30 eyes);and group of normal anterior chamber group with wide angle(NAC group,30 eyes).Measurements of ACD,anterior chamber volume(ACV),iris volume(IV),lens vault(LV),angle opening distance(AOD),angle recess area(ARA),trabecular iris space area(TISA),and trabecular iris angle(TIA)were conducted in each group before and 3mo after surgery.RESULTS:There was no significant difference in age,axial length(AL),corneal curvature,corneal diameter,intraocular pressure,and IV between two groups before surgery,except for the LV(P=0.000).ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation(3.69±0.38 vs 3.85±0.39 mm,P=0.025;161.37±19.47 vs 178.26±20.30 mm3,P=0.002).AOD750,ARA750 in nasal and inferior quadrants,TISA750 in all quadrants except temporal,and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation(all P<0.05).CONCLUSION:Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects,but the angle related parameters including AOD750,ARA750,TISA750,TIA,TISA750,and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level.
基金Supported by the Deputy of Research and Technology of Tehran University of Medical Sciences as a PhD Thesis.
文摘AIM:To determine the agreement of ocular biometric indices including axial length,keratometric readings,anterior chamber depth,and horizontal corneal diameter between the Pentacam AXL and IOL Master 500.METHODS:The study was a large cross-sectional population-based study(Tehran Geriatric Eye Study)conducted from Jan 2019 to Jan 2020.A total of 160 clusters were randomly selected proportional to size(each cluster contained 20 individuals)from 22 strata of Tehran city.All people aged 60y and above were invited to participate in the study.For all participants,preliminary ocular examinations were performed including the measurement of uncorrected and best-corrected visual acuity,objective and subjective refraction,anterior and posterior segment examinations.All participants underwent an ocular biometry using the Pentacam AXL and IOL Master 500.RESULTS:The 95%limits of agreement(LoA)between the two devices were-0.13 to 0.19,-0.15 to 0.17,and-0.13 to 0.19 in normal,pseudophakic,and cataractous eyes,respectively.With increasing the axial length,the difference between the two devices significantly increased in all three groups of normal,pseudophakic,and cataractous eyes(P<0.001).The 95% LoAs between the two devices regarding the mean keratometry shows that the best LoAs were seen in cataractous(-0.33 to 0.81)and followed by normal eyes(-0.36 to 0.86)and the pseudophakic eyes(-0.48 to 0.90)had the widest LoA.The 95% LoAs for horizontal corneal diameter measurements were-0.08 to 0.86,-0.03 to 0.83,and-0.07 to 0.87 in normal,pseudophakic,and cataractous eyes,respectively.The 95% LoAs of anterior chamber depth measurements between the two devices was-0.39 to 0.19 and-0.37 to 0.13 in normal eyes and cataractous,respectively.CONCLUSION:The Pentacam AXL has excellent agreement with the gold standard,IOL Master 500 in measuring axial length.In eyes with cataracts,the difference between the two devices is more scattered.With the increasing of axial length,the difference between the two devices increased,which should be considered when using Pentacam AXL.
基金Supported by the National Natural Science Foundation of China(No.81970792No.82171040)Medical Science and Technology Project of Health Commission of Henan Province(No.YXKC2020026)。
文摘·AIM:To describe the morphological characteristics of foveal avascular zone(FAZ)in normal Chinese adults with or without myopia by swept-source optical coherence tomography angiography(SS-OCTA)and analyze the possible associated factors.·METHODS:Normal Chinese adults with or without myopia aged between 18 and 60 y were recruited into the study.One eye in each individual was randomly selected for scanning using SS-OCTA.FAZ parameters,central retinal thickness(CRT)and central choroidal thickness(CCT)were then analyzed.Correlations between systemic and ocular variables and FAZ parameters were subsequently evaluated.The subgroup analysis based on refractive error was also carried out.·RESULTS:In total,127 eyes out of 127 normal subjects were finally included in the study(mean age29.5±8.22 y,61 males and 66 females).The pattern of FAZ was variable:round configuration in 28 eyes(22%),quadrilateral configuration in 23 eyes(18%),pentagonal configuration in 20 eyes(16%),oval configuration in 15 eyes(12%),triangular configuration in 6 eyes(5%)and irregular configuration in 35 eyes(28%).The mean area of FAZ was0.37±0.12 mm^(2).Females had a larger FAZ(0.41±0.11 mm^(2)vs0.32±0.11 mm^(2))compared with that of males(P<0.01).All myopic individuals showed smaller FAZ area and perimeter compared with that of normal individuals(P<0.01).There was no obvious correlation between age and FAZ.In the univariate regression analysis,both axial length(AL)and refractive error were significantly related to FAZ parameters.However,only CRT showed negative correlation with FAZ in the multivariate regression analysis.·CONCLUSION:The pattern of FAZ configuration in normal Chinese adults with or without myopia is highly variable.Establishing quantitative parameters of FAZ would not only provide details of macular pathophysiology but could possibly contribute as a biomarker in disease staging.
文摘AIMTo assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US).METHODSThere were 218 adult subjects (218 eyes) aged 59.2±9.2y enrolled in this prospective cross-sectional study. Forty-three eyes had open angles and 175 eyes had narrow angles. Routine ophthalmic exam was performed and nuclear opacity was graded using the Lens Opacities Classification System III (LOCS III). Lens thickness was measured by AS-OCT (Visante OCT, Carl Zeiss Meditec, Dublin, CA, USA). The highest quality image was selected for each eye and lens thickness was calculated using ImageJ software. Lens thickness was also measured by A-scan US.RESULTSInterclass correlations showed a value of 99.7% for intra-visit measurements and 95.3% for inter-visit measurements. The mean lens thickness measured by AS-OCT was not significantly different from that of A-scan US (4.861±0.404 vs 4.866±0.351 mm, P=0.74). Lens thickness values obtained from the two instruments were highly correlated overall (Pearson correlation coefficient=0.81, P<0.001), and in all LOCS III specific subgroups except in grade 5 of nuclear opacity. Bland-Altman analysis revealed a 95% limit of agreement from -0.45 to 0.46 mm. Lens thickness difference between the two instruments became smaller as the lens thickness increased and AS-OCT yielded smaller values than A-scan US in thicker lens (β=-0.29, P<0.001)CONCLUSIONAS-OCT-derived lens thickness measurement is valid and comparable to the results obtained by A-scan US. It can be used as a reliable noncontact method for measuring lens thickness in adults with or without significant cataract.
文摘In swept-source optical coherence tomography(SSOCT),the swept-source stimulates system by a series of wavelengths in time sequence;a photo detector then collects all reflected/backscattered light from testing sample as the components of Fourier series.Due to the nature of the SSOCT,the processing in spectral domain can merge multiple swept-sources with different central wavelengths,which greatly increases the resolution of the OCT imaging.In the wavelength probing OCT,a standard broadband SSOCT system is used to extract the internal structure of the sample,and another narrow band light can be used to probe the spectral feature of the sample at the probing wavelength.
基金Supported by National Natural Science Foundation of China(No.82271098No.81960177)+1 种基金Key Research and Development Program of Shaanxi Province(2024SF-YBXM-322)Institutional Foundation of the First Affiliated Hospital of Xi’an Jiaotong University(No.2021ZXY-10).
文摘AIM:To compare the dif ferences of choroidal neovascularization(CNV)measurements between sweptsource and spectral-domain optical coherence tomography angiography(SS-OCTA and SD-OCTA)in neovascular agerelated macular degeneration(nAMD)and the imaging reliability of the two devices.METHODS:Prospective comparative study.SS-OCTA and SD-OCTA were used to scan the same eye with the modes of 3×3 and 6×6 mm2 centered on the neovascularization.Only qualified images were chosen and the border of CNV was manually delineated by two graders independently.The area of CNV(ACNV),vascular perfusion density(PD),and vessel length density(VLD)within the delineation were calculated using Image J.The differences of CNV measurements between the two OCTA devices were compared using Bland-Altman analysis.The agreement between the two graders on the measurements of each device was compared using the intraclass correlation coefficient(ICC).RESULTS:A total of 18 patients(22 eyes)with nAMD were included.The measurements of ACNV,PD,and VLD were 7.247±4.586 and 4.901±3.741 mm^(2),43.202±9.636 and 34.904±10.489,6.339±1.228 and 5.908±1.741 mm^(-1) for SS-OCTA and SD-OCTA,respectively.The differences between the two devices were 2.346±3.030 mm^(2)(Z=-3.782,P<0.0001),8.298±14.160(Z=-2.419,P=0.016),and 0.431±2.114 mm^(-1)(Z=-0.828,P=0.408)for ACNV,PD and VLD,respectively.The ICC between two graders were 0.893(P<0.001),0.902(P<0.001),0.885(P<0.001)for ACNV,PD,VLD in SS-OCTA,and 0.971(P<0.001),0.976(P<0.001),0.973(P<0.001)in SD-OCTA,respectively.CONCLUSION:Both OCTA devices have high imaging reliability.Compared with SD-OCTA,SS-OCTA has a larger ACNV measurements,but doesn’t show better resolution of internal vessels of CNV and well signal strength.
