Ocular Biological Parameters Research Articles

Comparison of ranibizumab and conbercept treatment in type 1 prethreshold retinopathy of prematurity in zone II

PurposeThe treatment with anti-VEGF for Retinopathy of prematurity (ROP) has already been widely applied in clinics even though there are still many concerns about this treatment. In this project we investigated the clinical outcomes of intra-vitreous conbercept (IVC) and ranibizumab (IVR) injection for treating type 1 prethreshold ROP in Zone II.MethodsThe data of ROP infants receiving IVR or IVC from January 2017 to March 2020 who were followed up for at least 12 months in our hospital was studied in the present retrospective study. Regression, reactivation, complications, and ocular biological parameters were evaluated.ResultsOne hundred twenty-five eyes (64 infants) in IVC group and 229 eyes (117 infants) in IVR group were observed in the study. All infants showed good response to the two anti-VEGF agents. No eyes deteriorated during the observation. No significant difference was found between the two groups as to the regression within one week and one month, the reactivation rate, and the retreatment interval (p > 0.05) whereas retinal complete vascularization rate at 6 mons after the initial treatment and mean completion time of retinal vascularization after initial injection showed significant difference (p < 0.05). At 12 mons PMA the ocular parameters also presented no statistical difference between the two treated groups (p > 0.05). However, the ocular showed slight myopic tendency with the anti-VEGF treatment when compared to the control group (p < 0.05) whereas there was no statistical difference revealed between the two treated groups (p > 0.05).ConclusionsBoth conbercept and ranibizumab for treating type 1 prethreshold ROP in Zone II are safe and effective. They had little effect on the development of ocular whereas there was a slight tendency of myopia after the treatment.

Association Between Myopia and Pupil Diameter in Preschoolers: Evidence from a Machine Learning Approach Based on a Real-World Large-Scale Dataset.

Previous studies have explored the connections between various ocular biological parameters with myopia. Our previous study also found that pupil data can predict the myopic progression during the interventions for myopia. However, studies exploring the association between pupil diameter and myopia in preschoolers with myopia were lacking. Hence this study was aimed to investigate the association between pupil diameter and myopia in preschoolers with myopia based on a real-world, large-scale dataset. Data containing 650,671 preschoolers were collected from a total of 1943 kindergartens in Shenzhen, China. Refraction and pupil parameters were collected. After data filtering, the occurrence of myopia and its association with age, gender, pupil diameter, and other variables, were analyzed. Random forest (RF) and eXtreme gradient boosting (XGBoost) were selected from seven machine learning algorithms to build the model. The mean decrease accuracy (MDA), mean decrease Gini (MDG), and gain feature importance (GFI) techniques were employed to quantify the importance of pupil diameter and other features. After the assessments, 51,325 valid records with complete pupil data were included, and 3468 (6.76%) were identified as myopia based on the calculated cycloplegic refraction. Preschoolers with myopia presented reduced pupil diameter and greater variation (5.00 ± 0.99mm) compared to non-myopic preschoolers (6.22 ± 0.67mm). A nonlinear relationship was found according to the scatterplots between pupil diameter and refraction (R2 = 0.14). Especially preschoolers with myopia had reduced pupil diameter compared to emmetropic preschoolers, but hyperope did not experience additional pupil enlargement. After adjusting for other covariates, this relationship is still consistent (P < 0.001). XGBoost and RF algorithms presented the highest performance and validated the importance of pupil diameter in myopia. Based on a real-world large-scale dataset, the current study illuminated that preschoolers with myopia had a reduced pupil diameter compared to emmetropic preschoolers with a nonlinear pattern. Machine learning algorithms visualized and validated the pivotal role of pupil diameter in myopia. chictr.org Identifier: ChiCTR2200057391.

Ocular characteristics and outcomes of phacoemulsification in patients with cataract after renal transplantation.

To explore ocular characteristics of patients with cataracts after renal transplantation and analyze the results of phacoemulsification combined with intraocular lens (IOL) implantation. Patients with cataracts after renal transplantation and control patients who underwent phacoemulsification combined with IOL implantation were enrolled. All patients underwent phacoemulsification combined with IOL implantation. Visual acuity, intraocular pressure, type of lens opacity, corneal endothelial cell density, and ocular biological parameters were evaluated before surgery. Visual prognosis, dry eye, and postoperative complications were monitored for 6months after phacoemulsification. We analyzed 25 eyes of 16 patients after renal transplantation and 30 eyes of 21 control patients. The most common type of cataract of renal transplantation group was posterior subcapsular, while the most common type of cataract of control group was cortical. Significant differences in corneal astigmatism, white-to-white ratio, and keratometry values were observed between the groups. The postoperative visual acuity of both groups significantly improved following surgery. Postoperative complications, such as the degree of anterior and posterior capsule opacification and the incidence of a requirement of neodymium-doped yttrium aluminum garnet laser capsulotomy, were significantly lower in the renal transplantation group. Moreover, secondary glaucoma occurred in two eyes in the renal transplantation group. This study showed that cataracts after renal transplantation were mostly posterior subcapsular. Postoperative visual acuity recovered well in most patients, with reduced incidence of postoperative complications. This study suggested that phacoemulsification combined with IOL implantation was safe and effective, providing a reference for multi-focal IOL implantation in kidney transplant recipients.

Changes in Corneal Higher-Order Aberrations and Ocular Biometric Measurements after Phacoemulsification Combined with Goniosynechialysis in Primary Angle Closure/Glaucoma Patients.

To compare corneal higher-order aberrations (HOAs), refractive error, and ocular biological parameters before and after phacoemulsification combined with goniosynechialysis (Phaco-GSL) in primary angle closure/glaucoma (PAC/PACG) patients with different axial lengths (ALs). In this prospective study, cataract patients diagnosed with PAC/PACG were categorized into two groups based on their ALs: the short AL group (AL ≤ 22.5 mm) and the normal AL group (22.5 < AL ≤ 24.5 mm). The pre- and postsurgery measurements of intraocular pressure (IOP) and best-corrected visual acuity (BCVA) were conducted at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months. Additionally, the assessments included corneal HOAs, the number of antiglaucoma medications, visual field parameters, manifest refraction, and other ocular biological parameters before surgery and at the final follow-up. Prior to surgery, the two groups exhibited no significant differences, except for AL, curvature value, and Z (4, 0) of the posterior corneal surface (all P < 0.01). Following surgery, BCVA improved, and IOP decreased significantly in both groups (P < 0.01). Both anterior and total corneal HOAs, along with Z (3, -3), increased in the two groups (all P < 0.05), with the normal AL group exhibiting a significantly greater increase in total cornea Z (3, -3) than the short AL group (P=0.047). The normal AL group also exhibited a slight tendency towards hyperopia (P < 0.01). Significant changes were observed in the visual field index and mean deviation in both groups (P < 0.05). Phaco-GSL resulted in an increased corneal HOAs, particularly trefoil, with variations based on the patient's AL. Patients with normal ALs tended to shift towards hyperopia after surgery.

Observation of peripheral refraction in myopic anisometropia in young adults.

To investigate the differences in retinal refraction difference values (RDVs) of adult patients with myopic anisometropia compared with those without myopic anisometropia, and to investigate the relationship between ocular biometric measurements and relative peripheral refraction. This clinical observation study included 130 patients with myopia (-0.25 to -10.00 D) between October 2022 and January 2023 aged between 18 and 40y. The patients were divided into anisometropia (n=63; difference in binocular anisometropia ≥1.00 D) and non-anisometropia (n=67; difference in binocular anisometropia <1.00 D) groups accordingly. Ocular biometric measurements were performed by optical biometrics and corneal topography to assess the steep keratometry (Ks), flap keratometry (Kf), axial length (AL), corneal astigmatism (CYL; Ks-Kf), surface regularity index (SRI), surface asymmetry index (SAI), and central corneal thickness (CCT). The RDV was measured at five retinal areas from the fovea to 53 degrees (RDV-0-10, RDV-10-20, RDV-20-30, RDV-30-40, and RDV-40-53), the total RDV (TRDV) of 53 degrees, and four regions, including RDV-superior, RDV-inferior, RDV-temporal, and RDV-nasal. An analysis of Spearman correlation was carried out to examine the correlation between RDV and the spherical equivalent (SE) and ocular biological parameters. Within RDV-20-53, both groups showed relative hyperopic defocus, and the increase in RDV corresponds to the increase in eccentricity. In the myopic anisometropia group, the TRDV, RDV-20-53, RDV-superior, and more myopic eyes had significantly higher RDV-temporal values than less myopic eyes. (P<0.05). In the non-anisometropia group, there was no significant difference in the RDV between the more and less myopic eyes at different eccentricities (P>0.05). There was a negative correlation between SE and TRDV (r=-0.205, P=0.001), RDV-20-53 (r=-0.281, -0.183, -0.176, P<0.05), RDV-superior (r=-0.251, P<0.001), and RDV-temporal (r=-0.230, P<0.001), a negative correlation between CYL and RDV-10-30 (r=-0.147, -0.180, P<0.05), and a negative correlation between SRI and RDV-0-20 (r=-0.190, -0.170, P<0.05). AL had a positive correlation with RDV-20-30 (r=0.164, P=0.008) and RDV-temporal (r=0.160, P=0.010). More myopic eyes in patients with myopic anisometropia show more peripheral hyperopic defocus. Diopter and corneal morphology may affect peripheral retinal defocus.

Initial screening for occult congenital ectopia lentis based on ocular biological parameters in preschool children

BackgroundThis study aimed to identify an initial screening tool for congenital ectopia lentis (CEL) by comparing ocular biological parameters in children with myopia.MethodsA retrospective case-control study was conducted at one tertiary referral centre, from October 2020 to June 2022. Axial length (AL), corneal curvature (CC), refractive astigmatism (RA), corneal astigmatism (CA), internal astigmatism (IA), the difference between the axis of RA and CA [AXIS(RA-CA)], white-to-white corneal diameter (WTW), and axial length-corneal radius ratio (AL/CR) were compared in 28 eyes of CEL patients, and 60 eyes of myopic patients matched for age and refraction. The spherical equivalent of each eye was < -3.00 D. Area under the curve (AUC) of the receiver operating characteristic curves were calculated.ResultsThe differences in RA, AL, mean keratometry (Kmed), maximum keratometry (Kmax), minimum keratometry (Kmin), CA, IA, AXIS(RA-CA), WTW, and AL/CR between the CEL and myopic groups were statistically significant (p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001; p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001, respectively). In logistic regression analysis RA, IA, AXIS(RA-CA), and AL/CR were significantly associated with CEL (p < 0.05). AUCs for RA, IA, AXIS(RA-CA), and AL/CR were 0.694, 0.853, 0.814, and 0.960, respectively. AUCs for AL/CR in SE< -6.00 D subgroup was 0.970, and 0.990 in -6.00 D ≤ SE < -3.00 D group. An AL/CR < 3.024 was the optimal cut-off point differentiating the CEL and control groups (sensitivity, 92.9%; specificity, 88.30%).ConclusionsA smaller AL/CR could identify CEL in children with myopia. An AL/CR cut-off value of 3.024 may be the most sensitive and specific parameter for the differential diagnosis of CEL in patients with mild to high myopia.

Repeatability and Agreement between Scansys and Pentacam in Ocular Biological Parameters.

To assess the repeatability and agreement between Scheimpflug-based corneal topography, Scansys and Pentacam, in measuring ocular parameters in myopic eyes. A Grade-A tertiary hospital in Beijing, China. Cross-sectional study. The following measurements were performed in 204 patients undergoing pre-operative examinations for refractive surgery from the corneal curvature, astigmatism, corneal thickness, corneal volume, corneal asphericity, anterior chamber depth and volume, and pupil diameters. Repeatability was determined using intraclass correlation coefficient (ICC) with 95% confidence interval (95% CI), Cronbach's Alpha, coefficient of variation (CV), within-subject standard deviation (Sw), test-retest repeatability (TRT), and one-way analysis of variance (one-way ANOVA). The inter-device agreement was determined using paired t-test and Bland-Altman plots. Scansys showed good repeatability in the anterior and posterior corneal flattest meridian (Kf), steepest meridian (Ks), and mean (Km), axis of anterior corneal Ks, anterior corneal astigmatism, pupil central corneal thickness, central corneal thickness, corneal apex thickness, thinnest corneal thickness, corneal volume, photopic pupil diameter, anterior chamber depth and volume. In the agreement study, Bland-Altman plots showed that 95% LoA of corneal curvature, pupil central corneal thickness, corneal apex thickness, thinnest corneal thickness, and corneal volume generated by Scansys and Pentacam were narrow. There were no statistically significant differences in the anterior corneal Kf and Km. Scansys showed good repeatability in measuring corneal curvature of anterior and posterior surfaces, anterior corneal astigmatism, corneal thickness, corneal volume, photopic pupil diameter, anterior chamber volume and depth. Scansys and Pentacam can only be used interchangeably in measuring anterior corneal curvature.

Ocular biological parameters and prevalence of myopia in vocational high school and general high school in China.

Higher prevalence of myopia is possibly associated with more extended schooling schedules. Therefore, adjustments to high school curricula may aid in reducing the prevalence of myopia among adolescents. To investigate the prevalence of myopia among 15- to 18-year-old adolescents in Tianjin, China, and to evaluate the impact of different educational schedules on the prevalence of myopia among high school students. This is a school-based epidemiological study with a cross-sectional design. Ocular biological parameters and noncycloplegic photorefraction were examined using optical biometry devices and photoscreener devices. Each student's spherical equivalent (SE) and ocular biometry were recorded, and the prevalence of myopia was calculated. A total of 2,867 participants (1,519 males and 1,348 females) were tested for non-cycloplegic refraction, axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD) and lens thickness (LT). In this research, the overall prevalence of myopia was 81.6%, with high myopia accounting for 11.8%. Myopia prevalence was substantially higher in general high schools than in vocational high schools, with 86.1 and 70.1%, respectively. There were no significant differences in the prevalence of myopia (p = 0.744) or high myopia (p = 0.851) across the three vocational school years. In the general high school, however, there was an increase of 4.6% (p < 0.05) in myopia prevalence between year 10 and year12. Comparing vocational and standard high school students, there are considerable disparities in prevalence of myopia, spherical equivalent, and ocular biological parameters. The prevalence of myopia and high myopia increased among standard high school students, but remained relatively consistent among students in vocational schools.

Effects of atropine and tropicamide on ocular biological parameters in children: a prospective observational study

BackgroundThe effectiveness of cycloplegia in delaying the progression of myopia and its application in refractive examination in children have been extensively studied, but there are still few studies on the effects of atropine/tropicamide on ocular biological parameters. Therefore, the purpose of this study was to explore the effects of atropine/tropicamide on children's ocular biological parameters in different age groups and the differences between them.MethodsThis was a prospective observational study in which all school children were examined for dioptres and ocular biological parameters in the outpatient clinic, and 1% atropine or tropicamide was used for treatment. After examination, we enrolled the patients grouped by age (age from 2 to 12 years treated by atropine, 55 cases; age from 2 to 10 years treated by tropicamide, 70 cases; age from 14 to 17 years treated by tropicamide, 70 cases). The ocular biological parameters of each patient before and after cycloplegia were measured, and the difference and its absolute value were calculated for statistical analysis using an independent-samples t test.ResultsWe compared the value and the absolute value of the differences in ocular biological parameters before and after cycloplegia in the same age group, and we found that the differences were not statistically significant (P > 0.05). There were significant differences in the corresponding values of AL, K1 and ACD among the different age groups (P < 0.05). Before cycloplegia, there were significant differences in AL, K, K1, K2 and ACD in different age groups (P < 0.05). However, the differences in AL, K, K1, K2 and ACD among different age groups disappeared after cycloplegia (P > 0.05).ConclusionsThis study demonstrated that atropine/tropicamide have different effects on cycloplegia in children of different ages. The effects of atropine/tropicamide on ocular biological parameters should be fully considered when evaluating the refractive state before refractive surgery or mydriasis optometry for children of different ages.

Outcomes of surgical treatment of congenital cataract with microphthalmia in infancy

Objective: To examine the outcomes of surgical treatment for infants with congenital cataract and microphthalmia (CATM). Methods: It was a retrospective case series study. Data of 28 (55 eyes) CATM children who underwent cataract surgery at the Qingdao Eye Hospital of Shandong First Medical University and were followed up for more than 5 years between January 2010 and December 2014 under the age of 6 months. There were 15 male and 13 female children. The age at the time of surgery was (3.2±1.3) months, and the follow-up time was (8.2±1.7) years. The data included the basic information of the children, the ocular biological parameters before and after surgery and intraocular lens (IOL) implantation, and the occurrence of complications. Paired t-tests or Wilcoxon signed rank tests were used to compare groups, and logistic regression analysis was used to identify factors related to IOL implantation, secondary glaucoma, and visual axis opacification (VAO). Results: The mean preoperative axial length was (16.6±1.0) mm, and the mean horizontal corneal diameter was (9.5±0.9) mm. The axial growth rate within 2 years after the first stage of surgery was (1.4±0.8) mm/year. None of the children had an IOL implanted before the age of 2. Sixty percent of the eyes (33/55) received IOL implantation within 2 to 4 years after the first stage of surgery, while the remaining 40% (22/55) did not receive IOL implantation at the last follow-up. The axial growth rate was (0.9±0.7) mm/year within two years after the second stage of surgery. Postoperative secondary glaucoma occurred in 7 eyes (12.7%), and VAO occurred in 15 eyes (27.3%). IOL implantation was associated with preoperative axial length (OR=0.072, P<0.001) and age at the first stage of surgery (OR=7.270, P<0.001), but not with preoperative corneal diameter (P=0.735). The incidence of VAO was associated with preoperative corneal diameter (OR=4.124, P=0.011), but not with age at the first stage of surgery (P=0.489) or preoperative axial length (P=0.489). No factors related to the occurrence of secondary glaucoma were found. The best corrected visual acuity at the last follow-up after IOL implantation was (0.37±0.28) logMAR, which was better than that of children without IOL implantation (0.67±0.19) logMAR (U=49.50, P=0.003). Conclusions: Children with CATM can obtain the opportunity for IOL implantation through early surgery and ultimately achieve good visual outcomes. Properly selecting the timing for implanting IOL can keep the incidence of secondary glaucoma at an acceptable level.

The Guiding Significance of Ocular Biometry in Evaluating the Refractive Status of Preschool Children

Introductions: This study aimed to analyze the correlation between refractive status and ocular biological parameters in preschool-age children (3–6 years old), establish a regression curve, guide the clinical judgment of children’s refractive status, and improve the accuracy of refractive screening for this age group. Methods: A total of 508 children, aged 3–6 years, were admitted to the hospital, exhibiting symptoms of ametropia and a need for dilation optometry. Among these, 326 children were included in the statistics group, having been examined between August 2021 and October 2022, and 182 children were included in the validation group, having been examined between November 2022 and March 2023. Using IOL Master700, ocular biometry parameters were measured for all participants, including axial length (AL), keratometry readings (K1 and K2), anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT). One percent atropine sulfate eye gel was administered, and then the spherical equivalent (SE) was calculated by Bennett’s formula. The correlation between SE and other ocular biometrics was analyzed, followed by the establishment of an SE prediction equation. The SE prediction equation was used to calculate the spherical equivalent (SE#) using ocular biometry data from the validation group, and the consistency between SE and SE# was evaluated. Results: SE showed a negative correlation with AL/CR (r = −0.936), AL (r = −0.811), ACD (r = −0.500), age (r = −0.396), and Km (r = −0.213) (p < 0.001), and positive correlation with LT (r = 0.301), LP (r = 0.176) (p < 0.001). A multiple linear regression equation was established for SE using the stepwise selection method, SE = 49.232 – 23.583 × AL/CR + 1.703 × ACD + 0.589 × Km − 0.609 × LP + 1.103 × LT (R2 = 0.997). Based on the regression equation, the predicted SE# highly correlated with SE after cycloplegia in the validation group (r = 0.998, p < 0.001). Conclusion: The main ocular biological factors of ocular diopter in children aged 3–6 years are AL/CR, ACD, Km, LP, and LT, which are jointly influenced by multiple factors. Ocular biometry is a reliable predictor of real refraction among children aged 3–6.

Changes in ocular biological parameters after cycloplegia based on dioptre, age and sex

The effects of cycloplegia on ocular biological parameters in children have been extensively studied, but few studies have compared these parameters between different refractive states, ages, and sexes. Therefore, the purpose of this study was to investigate the changes in ocular biometry before and after cycloplegia in different groups based on dioptre, age and sex. We examined a total of 2049 participants in this cross-sectional study. A comprehensive eye examination was conducted before cycloplegia. Cycloplegia was implemented with the application of atropine or tropicamide. Ocular biological parameters were evaluated after cycloplegia, including axial length (AL), mean keratometry (K), flat keratometry (K1), steep keratometry (K2), central corneal thickness (CCT), anterior chamber depth (ACD) and white-to-white (WTW) distance. All the participants were categorized based on dioptre, age and sex. Statistical analysis was performed with paired t tests and Wilcoxon signed-rank tests. Regarding dioptre, AL was found to be increased significantly in the Fs, Ast and FA (p < 0.05) postcycloplegia groups. We observed significant increases in K, K1, K2 and ACD in the Fs group (p < 0.05) after cycloplegia. Regarding age, we found significant increases in AL, CCT and ACD in group 1 (p < 0.05), but AL decreased significantly in groups 2 and 3 (p < 0.05) postcycloplegia. There were no significant changes found in K, K1 and K2 in the three groups after cycloplegia (p > 0.05). Regarding sex, AL and WTW were found to decrease significantly among males and increase significantly among females (p < 0.05) postcycloplegia, while K, K1 and K2 showed the opposite trends. This study showed that there were differences in some ocular biological parameters after cycloplegia across different groups; in particular, there were significant differences in AL, CCT and ACD. Attention should be devoted to the influence of cycloplegia in clinical work.

A comparative study of the prevalence of myopia and behavioral changes in primary school students

ObjectiveTo analyze the changes in the prevalence of myopia and its relation to ocular biological parameters, and behaviors among primary school students in China, and understand the prevention and control of myopia.MethodsCross-sectional surveys were performed on 7–9-year-old children in the yrs. 2012 and 2019. In addition, spherical equivalent refraction (SER), axial length (AL), and AL/corneal radius ratio (AL/CR ratio) were collected without cycloplegia. Participants completed detailed questionnaires on behavior related to myopia.ResultsData was collected on 623 children (8.02 ± 0.57 years old) in 2012 and 536 students in 2019 (8.09 ± 0.65 years old). The prevalence of myopia was 37.7% in 2012 and 39.9% in 2019. The SER was -0.25 (0.92) D in 2012 and -0.25 (1.25) in 2019. There was no statistical difference in the prevalence of myopia and SER over the 7 years (all P > 0.05). In 2019, the prevalence of myopia among girls demonstrated an increasing trend (33.8% vs. 37.8%), but there was no statistical difference (P > 0.05). The mean AL and AL/CR ratio of boys were decreasing (all P < 0.05). The proportion of children reading more than 2 h and using digital devices for more than 2 h per day after their classes in the 2019 group both decreased (all P < 0.05). However, the proportion of activities performed outdoors for more than 2 h./day decreased significantly (P = 0.001).ConclusionCompared with 2012, the prevalence of myopia in primary school students in 2019 was under control, which may be related to the improvement of children's near-work behavior, but there was the problem of insufficient outdoor activity time. In terms of ocular biological parameters, the risk of myopia for boys in 2019 was lower.

Evaluation of the repeatability of optical coherence tomography in patients with age-related cataract associated with dry eye.

To assess the repeatability of a new optical biometer (OA-2000, Tomey, Japan) based on swept-source optical coherence tomography (SS-OCT) and Placido-disk topography in dry eyes with cataracts. A cross-sectional study was performed. Two hundred sixteen eyes of 216 cataract patients were enrolled in our hospital from March 2020 to December 2020. According to the subjective symptoms and objective examination of dry eye, the patients were assigned to dry eye group and non-dry eye group. Axial length (AL), keratometry readings (K), lens thickness (LT), anterior chamber depth (ACD), central corneal thickness (CCT) and white-to-white (WTW) distance were measured by one skilled operator. The repeatability of each parameter based on within-subject standard deviation (Sw), repeatability limit of standard deviation (2.77Sw), coefficient of variation (CoV) and intra-class correlation coefficient (ICC) was evaluated. There was no significant difference in age and gender between the two groups. NiaBUT and NifBUT in the dry eye group were significantly lower than those in the non-dry eye group (p < 0.05). The ICC mean values of AL, K1, K2, Km, ACD, LT and CCT were all greater than 0.960, except WTW. In the dry eye group, except CCT and WTW, the Sw scores for other biometric parameters were lower than 0.201, 2.77Sw scores were lower than 0.557, CoV(%) was less than 1%, and ICC mean values were greater than 0.964. Among them, the Sw scores for AL, LT and ACD were lower than 0.035, the 2.77Sw scores were lower than 0.097, and the ICC mean values are greater than 0.990. The ocular biological parameters measured by SS-OCT have good repeatability for age-related cataract patients with dry eyes, in which the AL, LT and ACD are the highest repeatable. However, more attention should be paid for WTW in clinical application since repeatability influence.

Ocular biometry of infants and young children with congenital cataract

Objective: To understand the developmental characteristics of early ocular biological parameters in patients with congenital cataract. Methods: Retrospective case series study. The ocular biometry data such as the axial length, corneal curvature, anterior chamber depth and central corneal thickness of 169 patients under 3 years old who were diagnosed with congenital cataract in Eye Hospital of Wenzhou Medical University (Hangzhou Branch) from June 2016 to June 2020 were reviewed, and they were analyzed by 3 age groups. There were 87, 41, and 41 patients in three age groups, 1 to 6 months, 7 to 12 months, and 13 to 36 months, respectively; 108 patients with bilateral affected eyes and 61 patients with unilateral affected eyes were included; 84 patients with partial opacity lens and 85 patients with total opacity lens were included. The right eyes of the patients with bilateral congenital cataract were selected for analysis. Statistical analysis of ocular biological parameters between groups was performed using the independent samples t-test and paired samples t-test. Statistical analysis of the relationship between age in months and biological parameters was performed using the Pearson's correlation test. Results: The axial length at the age of 1 to 6 months in the affected eyes of patients with bilateral cataract was (17.59±1.19) mm, it was shorter than the affected eyes of patients with unilateral cataract [(18.18±1.34) mm], and the axial length in the affected eyes of patients with unilateral cataract were shorter than the healthy eyes [(19.01±0.93) mm]. At the age of 7 to 12 months, the axial length in the affected eyes of patients with unilateral cataract [(19.89±0.74) mm] was shorter than the healthy eyes [(20.48±0.43) mm]. The differences were statistically significant (t=-2.06, -5.62, -3.47, all P<0.05). The axial length in the affected eyes with partial opacity at the age of 1 to 6 months was shorter than those with total opacity [(17.43±1.14) mm vs. (18.06±1.29) mm; t=-2.38, P=0.020]. The difference in axial length (affected eyes vs. healthy eyes) was significantly correlated with the age in months in partial cataract (r=0.53, P=0.001). The corneal curvature in the affected eyes of patients with unilateral cataract was flatter than the healthy eyes at the age of 7 to 12 months [(42.41±1.82) D vs. (43.19±1.96) D; t=-2.29, P=0.038], but was steeper at the age of 13 to 36 months [(43.36±2.32) D vs. (42.55±1.88) D; t=2.17, P=0.043]. The anterior chamber depth in the affected eyes of patients with unilateral cataract was less than the healthy eyes at the age of 1 to 6 months [(2.44±0.37) mm vs. (2.58±0.33) mm; t=-2.08, P=0.048].The central corneal thickness in the affected eyes of patients with unilateral cataract was thicker than the healthy eyes both at the age of 1 to 6 months and 7 to 12 months [(555.26±46.95) μm vs. (541.85±40.78) μm, (542.93±27.63) μm vs. (530.93±30.36) μm; t=3.82, 2.26; P=0.001, 0.040]. Conclusions: Congenital cataracts maybe affect the early development of axial length, corneal curvature, anterior chamber depth and central corneal thickness. The degree of lens opacity maybe affecte the early axial length development. The axial length in eyes with partial opacity can be shorter than those with total opacity before the age of 6 months, and thereafter gradually outnumbered the latter.

Comparative Study of Relative Peripheral Refraction in Children With Different Degrees of Myopia.

PurposeTo investigate the difference in the retinal refraction difference value (RDV) using multispectral refractive topography (MRT).MethodsNinety myopic participants, who met the enrolment requirements, were examined with an automatic optometer after mydriasis. According to the value of the spherical equivalent (SE), the participants were divided into Emmetropia group (E, +0.5D < SE < −0.5D), Low Myopia (LM, −0.5D < SE ≤ −3D), and Moderate and high Myopia (MM, −3D < SE ≤ −10D). The ocular biological parameters were detected by optical biometrics (Lenstar 900, Switzerland), including axial length (AL), lens thickness (LT), and keratometry (K1, K2). Furthermore, the MRT was used to measure the retinal RDV at three concentric areas, with 15-degree intervals from fovea into 45 degrees (RDV-15, RDV 15–30, and RDV 30–45), and four sectors, including RDV-S (RDV-Superior), RDV-I (RDV-Inferior), RDV-T (RDV-Temporal), and RDV-N (RDV-Nasal).ResultsIn the range of RDV-15, there was a significant difference in the value of RDV-15 between Group E (−0.007 ± 0.148) vs. Group LM (−0.212 ± 0.399), and Group E vs. Group MM (0.019 ± 0.106) (P < 0.05); In the range of RDV 15–30, there was a significant difference in the value of RDV 15–30 between Group E (0.114 ± 0.219) vs. Group LM (−0.106 ± 0.332), and Group LM vs. Group MM (0.177 ± 0.209; P < 0.05); In the range of RDV 30–45, there was a significant difference in the value of RDV 30–45 between Group E (0.366 ± 0.339) vs. Group LM (0.461 ± 0.304), and Group E vs. Group MM (0.845 ± 0.415; P < 0.05); In the RDV-S position, there was a significant difference in the value of RDV-S between Group LM (−0.038 ± 0.636) and Group MM (0.526 ± 0.540) (P < 0.05); In the RDV-I position, there was a significant difference in the value of RDV-I between Group E (0.276 ± 0.530) vs. Group LM (0.594 ± 0.513), and Group E vs. Group MM (0.679 ± 0.589; P < 0.05). In the RDV-T position, there was no significant difference in the value of RDV-T among the three groups. In the RDV-N position, there was a significant difference in the value of RDV-N between Group E (0.352 ± 0.623) vs. Group LM (0.464 ± 0.724), and Group E vs. Group MM (1.078 ± 0.627; P < 0.05). The RDV analysis in all directions among the three groups showed a significant difference between RDV-S and RDV-I in Group LM (P < 0.05). Moreover, the correlation analysis showed that SE negatively correlated with AL, RDV 30–45, RDV-S, RDV-I, and RDV-N.ConclusionsIn this study, there was a significant difference in the value of RDV among Group E, Group LM, and Group MM, and the value of RDV in Group MM was the highest on the whole. In the range of RDV 30–45, there was a growing trend with the increase in the degree of myopia among the three groups. Furthermore, the SE negatively correlated with AL, RDV 30–45, RDV-S, RDV-I, and RDV-N.

Effects of Hemodialysis on Intraocular Pressure and Ocular Biological Parameters in Different Angle Structures.

Purpose This study is aimed at evaluating the effects of hemodialysis on intraocular pressure (IOP) and exploring the possible factors affecting IOP. Methods Fifty-two patients with hemodialysis (HD) that were diagnosed with chronic renal failure by nephrology were divided into four groups: wide angle, narrow angle, extremely narrow angle, and closed angle. IOP, central anterior chamber depth (ACD), lens thickness (LT), angle opening distance (AOD), trabecular-iris angle (TIA), iris thickness (IT), and ciliary body thickness (CBT) were recorded before and after HD. The Pearson coefficient test was used to determine correlations among changes in IOP and AOD, ACD, TIA, IT, CBT, and LT. Results The IOP in the extremely narrow angle group had significant difference compared with that in the wide angle group and narrow angle group (P < 0.05, P < 0.01). In the narrow angle group, change in LT was positively correlated with change in IOP (P < 0.05). In the extremely narrow angle group, change in LT was positively correlated with change in IOP (P<0.01), whereas changes in AOD and TIA were negatively correlated with change in IOP (P < 0.01; P < 0.05). Conclusion The effect of HD on IOP varies with the structure of the anterior chamber. The increasing of IOP in the extremely narrow-angle group is related with the changes of structure of anterior chamber.

Inter-eye Differences in Ocular Biometric Parameters of Concomitant Exotropia.

Purpose: To evaluate the ocular biometric parameters in patients with constant and intermittent exotropia by the measurement of swept-source optical coherence tomography (SS-OCT) optical biometer OA-2000 and comparing it with the normal control subjects.Design: Cross-sectional case-control study.Participants: Fifty-five constant and 24 intermittent patients with exotropia with central fixation and 77 orthotropic normal control participants aged 4–18 years old.Methods: Non-contact and high-resolution optical biometric OA-2000 measurements were conducted under uniform ambient light conditions. The statistical analysis included intraclass correlation coefficient (ICC), Bland-Altman plot, and independent t-tests.Main Outcome Measures: Spherical equivalent (SE), ocular biological parameters such as pupil diameter (PD), anterior chamber depth (ACD), lens thickness (LT), and axial lengths (AL). The absolute values of inter-eye differences for SE, PD, ACD, LT, and AL were recorded as AnisoSE, AnisoPD, AnisoACD, AnisoLT, and AnisoAL, respectively.Results: AnisoSE (0.878 vs. 0.577, P = 0.019), AnisoAL (0.395 vs. 0.208, P = 0.001), AnisoACD (0.060 vs. 0.032, P < 0.001), AnisoLT (0.060 vs. 0.031, P = 0.002), and AnisoPD (0.557 vs. 0.340, P = 0.002) were significantly larger in concomitant patients with exotropia. The SE, AL, ACD, LT, and PD showed excellent binocular correlation with ICC values that ranged from 0.943 to 0.987 in control participants and from 0.767 to 0.955 in concomitant exotropia patients. Bland-Altman plots showed the wider range of agreement in patients with concomitant exotropia than the control participants (SE: 5.0288 vs. 3.3258; AL: 2.2146 vs. 1.3172; ACD:0.3243 vs. 0.1682; PD: 2.4691 vs. 1.9241; and LT:0.3723 vs 0.1858).Conclusion: Patients with concomitant exotropia showed larger inter-eye differences in SE, ACD, LT, PD, and AL. Advice should be given to suspicious children to avoid or delay the development of concomitant exotropia.

Endoscopy-guided in vivo evaluation of ciliary sulcus location in children with ectopia lentis.

ObjectiveTo assess a new method to measure the distance of the needle passage from the ciliary sulcus to the corneal limbus anterior border (CTC) in eyes with ectopia lentis directly in vivo via endoscopy and to further evaluate the correlations among the CTC, age, automated horizontal white-to-white distance (WTW), and ocular axial length (AL).MethodsThe WTW and AL were measured using an optical biometer. An intraocular endoscope was used during transscleral suture fixation of posterior chamber intraocular lenses to identify the true location of the ciliary sulcus. Linear regression analysis was used to assess the correlation between the CTC and other ocular biological parameters, including age, WTW, and AL.ResultsThirty eyes of 30 children with ectopia lentis were evaluated. A statistically significant correlation was found between age and the CTC. The CTC could be predicted by the equation CTC = 0.1313 × Age + 0.9666. No statistically significant correlations were found between CTC and WTW, CTC and AL, WTW and AL, or WTW and age.ConclusionEndoscopy is useful for precisely suturing intraocular lens haptics in the real ciliary sulcus. Age can be used as an equivalent parameter for prediction of the true ciliary sulcus location.

Comparison of IOL-Master 700 and IOL-Master 500 biometers in ocular biological parameters of adolescents.

To compare the differences and consistency of IOL-Master 700 biometers applying swept optical coherence tomography with the conventional IOL-Master 500 applying partial coherence interference in terms of the ocular biological parameters in adolescents with ametropia. A total of 110 adolescents (110 eyes) with ametropia were collected, including 55 males and 55 females; age 10.69±2.81y. Ocular biological measurements were taken by IOL-Master 700 and IOL-Master 500 respectively to obtain biological parameters including axial length (AL), mean corneal anterior surface keratometry (Km), anterior chamber depth (ACD), and horizontal corneal diameter (WTW). Paired t-test was used to compare the differences between the two instruments. The intra-group correlation coefficient (ICC) and the Bland-Altman analysis were used to evaluate the consistency of parameter measurements between the two instruments for the four biological parameters. Statistical analysis showed that there was no significant difference in the Km value measured by IOL-Master 700 and IOL-Master 500 (t=-1.644, P=0.116). The average differences of the AL, ACD, and WTW distances between the two instruments are 0.028, 0.101 and 0.064 mm respectively, and the differences are statistically significant (t=2.644, 12.505, 3.911, P<0.001). The consistency study results indicated high correlation in the measurement of AL, Km, ACD and WTW between the two instruments (ICC=0.994, 0.873, 0.927, 0.912). The novel biometric instrument IOL-Master 700 makes no difference with IOL-Master 500 in the measurement of Km. There are some differences in the values of AL, ACD, and WTW. However, the two instruments show good consistency in these four biological measurements. The measured values of Km are interchangeable between the instruments. These two types of biometrics can be used as mutual reference in consideration of that the differences in AL, ACD, and WTW measurements are not sufficient to produce clinically meaningful differences.