The effect of age on lens parameters and axial length among wide age range of Saudis: A prospective, cross-sectional study.

PURPOSE: The purpose of the study is to establish normative values of eye parameters such as lens thickness (LT), lens diameter (LD), and axial length (AXL) among wide age range of Saudis using Pentacam AXL and compare these values between gender, in addition to that, to find the correlation between the age and those parameters. METHODS: In this prospective cross-sectional study, we measured LT, LD, and AXL in 125 healthy Saudi controls aged between 8 and 60 years using OCULUS Pentacam AXL. The screening tests were performed for each subject to exclude any ocular abnormalities using slit lamp (Haag-Streit BQ 900), refractive error measured using auto refractometer (Topcon KR-1 Autorefractor/Keratometer), and subject who has spherical equivalent more than ± 4.00D and astigmatism more than 1.00DC was excluded from the study. The mean of three readings of LT, LD, and AXL was taken. All examination was applied on one eye (right eye). RESULTS: The overall mean and standard deviation of LT, LD, and AXL was 2.2 mm ± 0.5, 2.7 mm ± 0.6, and 23.8 mm ± 1.0, respectively. There was no statistically significant difference between males and females in these parameters in all age groups, except in Group 2 (age: 19-30 years), there was a statistically significant difference between males and females in AXL, mean difference (M = 0.48), and P = 0.015. The mean of LT and LD was negatively associated with age. However, there was no significant correlation between AXL and age. CONCLUSION: Normative values of LT, LD, and AXL have been established in wide age group of healthy Saudis; the findings of the present study can highlight not only the normal range of the different ocular parameters, namely LT, LD, and AXL, but also their variation with age and gender.

Anterior Chamber Depth and Lens Thickness Measurements in Pediatric Eyes: Ultrasound Biomicroscopy Versus Immersion A-Scan Ultrasonography.

OBJECTIVE: To compare anterior chamber depth (ACD) and lens thickness (LT) measurements by ultrasound biomicroscopy (UBM), A-scan cross vector (CV) overlay with UBM, and immersion A-scan technique in pediatric eyes. METHODS: This prospective comparative cohort study comprised 43 eyes of 25 pediatric participants (mean age: 2.3±2.2 y). UBM and immersion A-scan biometry were performed prior to dilation and intraocular surgery. ACD and LT were measured by UBM image analysis, A-scan CV UBM overlay, and immersion A-scan technique. RESULTS: ACD and LT measurements obtained using immersion A-scan were significantly greater than with UBM image analysis with mean differences of 0.52 mm and 0.62 mm, respectively (p < 0.001). Immersion A-scan and UBM measurements were moderately correlated (r = 0.70 and 0.64, p < 0.001). ACD and LT measurements obtained using CV overlay were not significantly different than UBM measurements and the values were strongly positively correlated (r = 0.95 and 0.93, p < 0.001). CONCLUSION: Immersion A-scan may overestimate ACD and LT compared to UBM in pediatric patients due to oblique placement of the A-scan probe relative to the optical axis. Supplemental use of UBM and/or CV overlay is indicated to improve measurement accuracy in pediatric patients who cannot reliably fixate due to the ability to confirm proper alignment of the probe with the pupil by visualizing the anterior segment.

Influence of Lens Thickness on Accuracy of Kane, Hill-RBF 3.0, Barrett Universal II, Emmetropia Verifying Optical, and Pearl-DGS Formulas in Eyes with Nonhigh Myopia and High Myopia.

PURPOSE: To investigate the influence of lens thickness (LT) on accuracy of Kane, Hill-RBF 3.0 Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO), and Pearl-DGS formulas in eyes with different axial lengths (AL). METHODS: The prospective cohort study was conducted at Eye and ENT Hospital of Fudan University. Patients who had uneventful cataract surgery between March 2021 and July 2023 were recruited. Manifest refraction was conducted two-month post-surgery. Eyes were divided into 4 groups based on AL: short (<22mm), medium (22-24.5 mm), medium long (24.5-26mm) and very long (≥26mm). In each AL group, eyes were then divided into 3 subgroups based on the LT measured with IOLmaster700: thin (<4.5 mm), medium (4.5-5.0 mm), and thick (≥ 5 mm). The influence of LT on accuracy of Kane, Hill-RBF 3.0, BUII, EVO, and Pearl-DGS formulas were investigated in each AL group. RESULTS: A total of 327 eyes from 327 patients were analyzed, with 64, 102, 73 and 88 eyes in each AL group, respectively. In eyes with AL < 24.5 mm, myopic PE was significantly associated with greater LT using all the 5 formulas (all p < 0.05). Backward stepwise multivariate regression analyses revealed that LT was an important influencing factor for PE in all 5 formulas, particularly in eyes with AL <24.5 mm. In eyes with AL <24.5 mm and LT > 5.0 mm, PE of all 5 formulas calculated with the optional parameter LT were more myopic than those calculated without LT. CONCLUSIONS: Thicker LT was associated with more myopic PE among eyes with AL <24.5 mm when using all 5 formulas. Further optimization of current formulas is necessary, especially for eyes with short AL and thick LT.

Correlation of Ocular Biometry with Axial Length in Elderly Japanese.

Purpose: Ocular parameters are not only useful for diagnosing diseases but also for guiding treatment approaches. A lot of previous studies have reported ocular parameters and its relations before cataract surgery. However, despite ethnic differences in ocular biometry, few reports have dealt with Japanese. Hence, this retrospective cross-sectional study aimed to measure parameters of preoperative cataract patients and examines the correlations between each parameter in Japanese elderly people. Patients and Methods: The 210 subjects had their ocular axial lengths measured with OA-2000. The endpoints were ocular axial length (AL), central corneal thickness (CCT), average anterior corneal radius of curvature (CR), white-to-white (WTW), anterior chamber depth (ACD), and lens thickness (LT). Our analyses utilized the eye with the longer AL in each person. Each parameter was analyzed for correlations in a round-robin manner. Regression analyses were performed on parameters correlated with AL. Results: The parameters correlated with AL were CR (r = 0.33, P < 0.0001), WTW (r = 0.29, P < 0.0001), ACD (r = 0.59, P < 0.0001), and LT (r = -0.30, P < 0.0001). These parameters related to AL in all simple regression equations (CR (P < 0.0001), WTW (P = 0.0002), ACD (P < 0.0001), LT (P = 0.0001)). In multiple regression analyses, CR, ACD, and LT might relate to AL (CR (P = 0.0002), ACD (P < 0.0001), LT (P = 0.018)). LT tended to be thinner as AL increased, while CR, WTW, and ACD tended to increase. Conclusion: This information may be useful in developing strategies for ophthalmic surgery, as it provides information on the location of intraocular tissues. Various parameters have been used in intraocular lens (IOL) power calculations in recent years and knowledge of the interrelationship among parameters may be useful in determining IOL power according to ethnicity in the future.

Central anterior chamber depth correlated with white-to-white distance in normal, long, and short eyes.

PURPOSE: To explore the associations between central anterior chamber depth (CACD) and other anterior segment biometric parameters and to determine the possible determinants of CACD in short, normal, and long eyes. METHODS: The biometric data of pre-operation patients aged 50-80 years with coexisting cataract and primary angle-closure disease or senile cataract were reviewed. Axial length (AL), CACD, lens thickness (LT), central corneal thickness (CCT), and white-to-white distance (WTW) were measured by Lenstar optical biometry (Lenstar 900). The data of 100 normal eyes (AL = 22 to 26 mm), 100 short eyes (AL ≤ 22 mm), and 100 long eyes (AL ≥ 26 mm) were consecutively collected for subsequent analyses. RESULTS: The mean age of the subjects was 66.60 ± 7.85 years, with 25.7% of the sample being men. Both CACD and WTW were found to be smallest in short eyes and were smaller in normal eyes than in long eyes (F = 126.524, P < 0.001; F = 28.458, P < 0.001). The mean LT was significantly thicker in short eyes than in normal and long eyes (4.66 mm versus 4.49 mm versus 4.40 mm; F = 18.099, P < 0.001). No significant differences were observed in CCT between the three AL groups (F = 2.135, P = 0.120). Stepwise regression analysis highlighted AL, LT, and WTW as three independent factors associated with CACD in the normal AL group. In the short AL group and long AL group, LT and WTW were independent factors associated with CACD. CONCLUSIONS: CACD increases as AL elongates and reaches a peak when AL exceeds 26 mm. Furthermore, CACD showed inverse correlation with LT and positive correlation with WTW. A relatively small WTW results in an anteriorly positioned lens, and thus, a decrease in CACD.

Associations between axial length, corneal refractive power and lens thickness in children and adolescents: The Ural Children Eye Study.

PURPOSE: To assess relationships between ocular biometric parameters in dependence of age and sex in children and adolescents. METHODS: In the Ural Children Eye Study, a school-based cohort study, 4933 children underwent an ophthalmological and general examination. RESULTS: Complete biometric measurements were available for 4406 (89.3%) children. Cycloplegic refractive error (mean: -0.87 ± 1.73 diopters (D); median: -0.38 D; range: -19.75 D to +11.25 D) increased (multivariable analysis; r2 = 0.73) with shorter axial length (ß: -0.99; non-standardized regression coefficient B: -1.64; 95% CI: -1.68, -1.59) and lower corneal refractive power (ß: -0.55; B: -0.67; 95% CI: -0.70, -0.64), in addition to higher cylindrical refractive error (ß: 0.10; B: 0.34; 95% CI: 0.27, 0.41), thinner lens (ß: -0.11; -0.85; 95% CI: -1.02, -0.69) and male sex (ß: 0.15; B: 0.50; 95% CI: 0.42, 0.57). In univariate analysis, decrease in refractive error with older age was more significant (ß: -0.38 vs. ß: -0.25) and steeper (B: -0.22 (95% CI: -0.24, -0.20) vs. B: -0.13 (95% CI: -0.15, -0.11)) in girls than boys, particularly for an age of 11+ years. Axial length increased with older age (steeper for age <11 years) (B: 0.22 (95% CI: 0.18, 0.25) vs. 0.07 (95% CI: 0.05, 0.09)). In multivariable analysis, axial length increased with lower refractive error (ß: -0.77; B: -0.42; 95% CI: -0.43, -0.40) and lower corneal refractive power (ß: -0.54; B: -0.39; 95% CI: -0.41, -0.38), in addition to older age (ß: 0.04; B: 0.02; 95% CI: 0.01, 0.03), male sex (ß: 0.13; B: 0.23; 95% CI: 0.21, 0.32), higher cylindrical refractive error (ß: 0.05; B: 0.09; 95% CI: 0.05, 0.14) and thinner lens (ß: -0.14; B: -0.62; 95% CI: -0.72, -0.51). The axial length/corneal curvature (AL/CR) ratio increased until the age of 14 years (ß: 0.34; B: 0.017; 95% CI: 0.016, 0.019; p < 0001), and then became independent of age. The AL/CR ratio increased (r2 = 0.78) mostly with higher corneal refractive power (ß: 0.25; B: 0.02; 95% CI: 0.02, 0.02; p < 0.001), lower refractive error (ß: -0.75; B: -0.05; 95% CI: -0.05, -0.05; p < 0.001), thinner lens thickness (ß: -01.6; B: -0.09; 95% CI: -0.10, -0.08; p < 0.001) and older age (ß: 0.16; B: 0.006; 95% CI: 0.005, 0.007; p < 0.001). CONCLUSIONS: In this multiethnic group of school children in Russia, the age-related increase in myopic refractive error was more significant and steeper in girls, particularly for the age group of 11+ years. Determinants of higher myopic refractive error were longer axial length, higher corneal refractive power, lower cylindrical refractive error, thicker lens and female sex.

Comparison of the ocular ultrasonic and optical biometry devices in the different quality measurements

Purpose: To compare the reliability and agreement of axial length (AL), anterior chamber depth (ACD), and lens thickness (LT) measurements obtained with optical biometry based on swept-source optical coherence tomography (IOLMaster 700; Carl Zeiss, Germany) and an ultrasound biometry device (Nidek; US-4000 Echoscan, Japan) in different qualities of AL measurement. Methods: A total of 239 consecutive eyes of 239 cataract surgery candidates with a mean age of 56 ± 14 years were included. The quality measurements were grouped according to the quartiles of SD of the measured AL by IOLMaster 700. The first and fourth quartile's SD are defined as high and low-quality measurement, respectively, and the second and third quartiles’ SD is defined as moderate-quality. Results: The reliability of AL and ACD between the two devices in all patients and in different quality measurement groups was excellent with highly statistically significant (AL: all ICC=0.999 and P<0.001, ACD: all ICC>0.920 and P<0.001). AL and ACD in all quality measurements showed a very strong correlation between devices with highly statistically significant. However, there was poor (ICC=0.305), moderate (ICC=0.742), and good (ICC=0.843) reliability in measuring LT in low-, moderate-, and high-quality measurements, respectively. LT showed a very strong correlation (r = 0.854) with highly statistically significant (P<0.001) between devices only in patients with high-quality measurements. Conclusions: AL and ACD of the IOLMaster700 had outstanding agreements with the US-4000 ultrasound in different quality measurements of AL and can be used interchangeably. But LT should be used interchangeably cautiously only in the high-quality measurements group. (AU)

Capsulotomy enlargement after femtosecond laser treatment among cataract patients of different age groups: a retrospective case series.

PURPOSE: Larger-than-planned capsulotomies can occur, yet their association with age and eye parameters remains poorly understood. This study aimed to assess capsulotomy enlargement after femtosecond laser treatment in cataract surgery and to explore a possible correlation of capsulotomy enlargement with age and eye parameters. METHODS: This retrospective case series included consecutive patients diagnosed with cataracts between 05/2018 and 11/2019. Among them, patients within the age ranges of <18, 18-49, and ≥50 years were assigned to the childhood cataract (CC), young adult cataract (YAC), and age-related cataract (ARC) groups, respectively. The capsulotomy enlargement ratio (CER), age, degree of cataract, lens thickness (LT), axial length, and anterior chamber depth were recorded and analyzed. RESULTS: A total of 155 participants (179 eyes) were enrolled. The CER was significantly different among the three groups (CC: 1.245 vs. YAC: 1.060 vs. ARC: 1.029, P<0.001). The CER was found to be independently associated with both age (ß=-0.011 (0.001), P<0.001) and LT (ß=-0.049 (0.017), P=0.006) in the CC group, but it was only independently correlated with age (ß=-0.004 (0.001), P=0.002) in the YAC group and LT (ß=-0.014 (0.007), P=0.048) in the ARC group. CONCLUSIONS: Capsulotomy enlargement can occur after femtosecond laser treatment in cataract surgery, especially in the non-adult group. Age was a determinant of the CER in CC and YAC groups, while LT was an independent determinant of the CER in CC and ARC groups. These two factors should be taken into consideration for more precise sized capsulotomy.

Accuracy of Different Lens Power Calculation Formulas in Patients With Mature Cataracts.

Introduction To compare the prediction accuracy of lens power calculation formulas in patients undergoing mature cataract surgery. Methods A total of 90 operations involving the Alcon SA60AT IOL implant (Alcon, Geneva, Switzerland) were analyzed in terms of mean refractive prediction error (PE) and mean absolute prediction error (MAE) using backward calculation in a retrospective design. Results A negative PE was observed in SRK/T, Holladay 1, Holladay 2, Hoffer Q, Haigis, and Emmetropia Verifying Optical (EVO) formulas. In contrast, positive PEs were observed in Barrett Universal II (BAUII), Kane, and Radial Basis Function (RBF) formulas. Negative PE was observed with all formulas, except BAUII, in patients with a shallow anterior chamber depth (ACD). While the SRK/T, Holladay 1, BAU, Kane, and RBF formulas demonstrated positive PE, the Holladay 2, Hoffer Q, Haigis, and EVO formulas indicated negative PE. In patients with deep ACD, positive PE was observed in all formulas, barring Holladay 2 and EVO. No significant differences were identified between the formulas concerning MAE and percentages of 0.25 diopter (D), 0.50 D, 0.75 D, and 1.0 D across all study groups. Conclusion Although the new generation formulas provide very good results, achieving the best with a single formula is still impossible.

Comparison of the ocular ultrasonic and optical biometry devices in the different quality measurements.

PURPOSE: To compare the reliability and agreement of axial length (AL), anterior chamber depth (ACD), and lens thickness (LT) measurements obtained with optical biometry based on swept-source optical coherence tomography (IOLMaster 700; Carl Zeiss, Germany) and an ultrasound biometry device (Nidek; US-4000 Echoscan, Japan) in different qualities of AL measurement. METHODS: A total of 239 consecutive eyes of 239 cataract surgery candidates with a mean age of 56 ± 14 years were included. The quality measurements were grouped according to the quartiles of SD of the measured AL by IOLMaster 700. The first and fourth quartile's SD are defined as high and low-quality measurement, respectively, and the second and third quartiles' SD is defined as moderate-quality. RESULTS: The reliability of AL and ACD between the two devices in all patients and in different quality measurement groups was excellent with highly statistically significant (AL: all ICC=0.999 and P<0.001, ACD: all ICC>0.920 and P<0.001). AL and ACD in all quality measurements showed a very strong correlation between devices with highly statistically significant. However, there was poor (ICC=0.305), moderate (ICC=0.742), and good (ICC=0.843) reliability in measuring LT in low-, moderate-, and high-quality measurements, respectively. LT showed a very strong correlation (r = 0.854) with highly statistically significant (P<0.001) between devices only in patients with high-quality measurements. CONCLUSIONS: AL and ACD of the IOLMaster700 had outstanding agreements with the US-4000 ultrasound in different quality measurements of AL and can be used interchangeably. But LT should be used interchangeably cautiously only in the high-quality measurements group.

Effect of low-dose atropine (0.01%) on crystalline lens power among school-aged children with progressive myopia.

PURPOSE: To evaluate the change in crystalline lens power (LP) in a cohort of Indian children with progressive myopia receiving atropine (0.01%) compared with an untreated control group. DESIGN: Nonrandomised clinical trial. METHODS: The study included 120 children (70 in the atropine group; 50 in the control group) with progressive myopia (≥0.5 D/year) with a 1-year follow-up. The atropine group received 0.01% atropine eye drops once daily in both eyes, whereas the control group received no treatment. Changes in cycloplegic spherical equivalent, axial length (AL), keratometry (KER), anterior chamber depth (ACD) and lens thickness (LT) were recorded. LP was calculated using the formula proposed by Bennett. RESULTS: Mean myopia progression at year 1 was significantly less in the atropine group (-0.18 D [0.2]) than in the control group (-0.59 [0.21]; p < 0.001). The increase in AL was significantly different between the two groups (atropine: 0.21 mm [0.12]; control: 0.29 mm [0.11], p < 0.001). A significantly greater loss of LP was noted in the atropine group (-0.67 D [0.34]) than in the placebo group (-0.28 D [0.42]; p < 0.001). The change in LT was significantly different between the atropine and control groups (p = 0.02), whereas the change in ACD and KER was similar in the two groups. CONCLUSION: The greater loss of LP could contribute to the anti-myopia effect of atropine and should therefore be evaluated in studies reporting the efficacy of atropine on myopia to assess its actual effect on myopic progression.

Assessment of the biometric modifications of the eye in LASIK during suction.

PURPOSE: To study the biometric modifications of the eyeball during suction in Laser assisted in Situ Keratomileusis (LASIK). METHODS: Observational and cross-sectional study. We studied 43 patients who underwent surgery for myopia and myopic astigmatism. Mean age was 38.3 ±â€¯11.5 years, and 19 were female (44.2%). Conventional LASIK surgery with a manual microkeratome was performed. Before and during the suction maneuvre the following parameters were measured using an 11 Mhz biometric probe: aqueous depth (AQD), lens thickness (LT), vitreous cavity length (VCL) and axial length (AXL). Paired t-test was used to compare the biometric measurements before and during suction. RESULTS: The mean spherical equivalent refractive error was -4.5 ±â€¯2.3 diopters. During suction, the AQD did not change significantly (p = 0.231). However, AXL and VCL increased by 0.12 mm and 0.22 mm respectively (p = 0.039 and <0.01) and LT decreased by 0.20 mm (p < 0.01). AXL increased in 42% of the eyes and decreased in 16%, VCL increased in 70% of the eyes and decreased in 9%, and the LT was reduced in 67% of the eyes. CONCLUSIONS: Suction maneuvres during LASIK surgery produce changes of little magnitude in the eye globe, mainly a decrease in LT and an increase in VCL and AXL. Therefore, these modifications are expected to produce minimal anatomic alterations.

Relationship between the main components of the crystalline lens and the anterior chamber depth after cataract formation.

PURPOSE: To assess the relationship between anterior chamber depth (ACD) and lens thickness (LT), as well as its three main components (anterior and posterior cortex and nucleus thickness), in cataractous and non-cataractous eyes, depending on the axial length (AxL). METHODS: Anterior and posterior cortex and nucleus thickness of the crystalline lens, ACD, and AxL were measured using optical low-coherence reflectometry in cataractous and non-cataractous eyes. They were also classified into hyperopia, emmetropia, myopia, and high myopia, depending on AxL; thus, eight subgroups were created. A minimum sample size of 44 eyes (of 44 patients) for each group was recruited. Linear models were fitted for the whole sample and each AxL subgroup to assess if there were differences in the relationships between the crystalline lens variables and ACD, including age as a covariate. RESULTS: Three hundred seventy cataract patients (237 females, 133 males) and 250 non-cataract controls (180 females, 70 males), aged 70.5 ± 9.4 and 41.9 ± 15.5 years, respectively, were recruited. The mean AxL, ACD, and LT for the cataractous and non-cataractous eyes were 23.90 ± 2.05, 24.11 ± 2.11, 2.64 ± 0.45, and 2.91 ± 0.49, 4.51 ± 0.38, 3.93 ± 0.44 mm, respectively. The inverse relationship of LT, anterior and posterior cortex, and nucleus thickness with ACD was not significantly (p ≥ 0.26) different between cataractous and non-cataractous eyes. Further subclassification of the sample depending on AxL showed that the inverse relationship between the posterior cortex and ACD was no longer significant (p > 0.05) for any non-cataractous AxL group. LT, anterior and posterior cortex, and nucleus thickness was not significantly (p ≥ 0.43) different between cataractous and non-cataractous eyes for the whole sample, and all AxL groups after adjusting for age. CONCLUSIONS: The presence of cataracts does not modify the inverse relationship of the LT, anterior and posterior cortex, and nucleus with ACD. And this relationship does not seem to depend importantly on AxL. Besides, the possible differences in LT, anterior and posterior cortex, and nucleus between cataractous and non-cataractous eyes may not be caused by lens opacification, but possibly by the progressive lens growth due to aging.

Is myopia accelerated in type 1 diabetes mellitus children? Analyses from the ocular parameters.

BACKGROUND: This study compares the ocular biometry with or without myopia in children with type 1 diabetes mellitus (T1DM) and healthy children in China to analyse the difference between myopia in T1DM and healthy children. METHODS: A case-control study was conducted at the Children's Hospital of Fudan University. The children were divided into four subgroups depending on myopia or non-myopia, T1DM or non-DM. The participants were evaluated for anterior chamber depth (ACD), lens thickness (LT), axial length (AL), average keratometry (K) and lens power (P). Furthermore, cycloplegic refraction was performed and the spherical equivalent (SE) was acquired. RESULTS: One hundred and ten patients with T1DM and 102 healthy subjects were included in this study. In the age-sex adjusted analysis, the myopia T1DM subgroup showed thicker LT (p = 0.001), larger P (p = 0.003) and similar ACD, AL, K and SE (all p > 0.05) compared to the myopia control subgroup. Additionally, the myopia T1DM subgroup showed longer AL (p < 0.001) and similar ACD, LT, K and P (all p > 0.05) as the non-myopia T1DM subgroup. In the multivariate linear regression, for T1DM patients, eyes with longer AL, shallower ACD, and larger P were associated with a decrease in SE (p < 0.001, p = 0.01, and p < 0.001, respectively). Meanwhile, for healthy controls, eyes with longer AL and larger P were associated with a decrease in SE (all p < 0.001). CONCLUSIONS: The ACD and LT of myopia T1DM children remained unchanged compared to non-myopia T1DM children. This means that the lens in the former group could not lose power as compensation for AL growth, thus providing evidence for the acceleration of myopia in T1DM children.

A quantitative trait GWAS on lens thickness identifies novel risk loci on PTPRM in the narrow angle individuals susceptible to PACG.

PURPOSE: PACG is one of the leading causes of blindness where lens thickness is a major risk factor for narrow-angle individuals. To our knowledge, no literature has been reported on candidate gene for lens thickness as a quantitative trait (QT). Here, we performed a genome-wide association analysis on lens thickness in the narrow-angle individuals. MATERIALS AND METHODS: We conducted a genome-wide association study (GWAS) in the narrow angle individuals to investigate comprehensive genetic insights on lens thickness. RESULTS: In QT-GWAS, we identified 145 genome-wide suggestive significant loci in the discovery cohort. Subsequently, we observed 13 SNPs that showed statistical significance around the region of PTRRM. Regional association analysis for top significant genotyped variants identified PTPRM as the most likely candidate for increased LT. Integrative bioinformatic analyses confirmed that the associated genomic region has potential regulatory roles for modulating transcription as enhancers. In the replication cohort, the sentinel genotype SNP was further associated significantly (P-value =0.000448) with high LT individuals. In both cohorts, the T allele of rs1941137 in the PTPRM gene indicates as a risk allele for the increased LT. CONCLUSION: In this study, we discovered evidence of a genomic association between chromosomal areas around the PTPRM and increased lens thickness, resulting in a narrow angle. The regulatory components corresponding to PTPRM variations might have a role in the thicker lens. We report that the genomic region near PTPRM, a gene of potential interest, is associated with increased lens thickness.

Long-term follow-up of changes in ocular biometric parameters in orthokeratology lens wearers with relatively large-scale axial length reduction.

BACKGROUND: To investigate ocular biological characteristics for myopic children with axial length (AL) reduction during orthokeratology (Ortho-K) treatment and provide clinical clues for better myopia control effects. METHODS: Changes in ocular parameters and treatment zone (TZ) in 75 subjects who completed one-year Ortho-K treatment were retrospectively reviewed. The subjects were divided into two groups according to one-year AL change: the AL reduction group (n = 37) and the AL elongation group (n = 38). Univariate and multivariate regression analyses were performed to determine the association between TZ, ocular parameters, and AL change. RESULTS: There was no significant difference in baseline between the two groups (all P > 0.05). After one year of Ortho-K treatment, compared with those in the AL elongation group, children in the AL reduction group had a decreased anterior chamber depth (ACD) (P < 0.001), thickened crystalline lens thickness (CLT) (P = 0.002), thinned vitreous chamber depth (VCD) (P < 0.001) and smaller TZ (P = 0.03), but no difference in central corneal thickness (CCT) and pupil diameter (PD). In the multivariable analyses, AL reduction was negatively associated with baseline age (beta: - 0.048; 95% CI: - 0.083 to - 0.013; P = 0.009) and positively associated with the TZ (beta: 0.024; 95% CI: 0.009 to 0.040; P = 0.003). CONCLUSIONS: In AL reduction eyes, thickened CLT, decreased ACD and thinned VCD were observed during Ortho-K treatment, which could be suggested as indicators for better myopia control effects in the clinic. Older baseline age and smaller TZ wearing Ortho-K were also associated with AL change. Thickened CLT may be a result of compensation for AL-reduction eyes.

Effects of Long-Term Wear and Discontinuation of Orthokeratology Lenses on the Eyeball Parameters in Children with Myopia.

Objective: To evaluate the effects of long-term wear and discontinuation of the orthokeratology lenses (Orth-K) on the biological parameters of eyeballs in children with myopia. Methods: In this prospective study, a total of 308 subjects with myopia were randomized to receive Orth-K (n = 154) or single vision spectacles (SVS) (n = 154) for 12 months followed by a 1-month withdrawal period. The axial length (AL), the central corneal thickness (CCT), the anterior chamber depth (ACD) and the central lens thickness (CLT) were assessed at the baseline, 6 months, 12 months, and 13 months (1-month after lens withdrawal). Results: A total of 279 subjects completed the 13-month follow-up (142 in Orth-K group and 137 in SVS group). No statistical difference was noted in AL, CCT, ACD and CLT between the two groups at the baseline (all p > 0.05). However, compared with the baseline, the AL from the two groups became elongated 12 months after wearing Orth-K or SVS. The increase of AL in Orth-K group was 0.22 ± 0.11 mm, significantly smaller than 0.35 ± 0.08 mm in SVS group (p < 0.05). In addition, CCT in Orth-K group was 544.26 ± 11.69 µm at 12 months, significantly thinner than 550.49 ± 12.13 µm in SVS group (p < 0.05). Interestingly, the change in CCT between the baseline and 1-month after withdrawal of the lens was not statistically different in either group (all p > 0.05). Furthermore, at 12-months, CLT in Orth-K group was 3.35 ± 0.21 mm, significantly thicker than 3.31 ± 0.15 mm at baseline and thicker than 3.30 ± 0.05 mm in SVS group at 12 months (all p < 0.05). Lastly, ACD was not statistically different between Orth-K and SVS groups at any time point (p > 0.05). Conclusion: Orthokeratology lenses can effectively retard axial elongation, reversibly reduce CCT, increase CLT in myopic children, but have no obvious effect on ACD, indicating that Orth-K may significantly retard myopia without noticeable myopia rebound after interruption of Orth-K.

Biometric Variations in High Myopia Associated with Different Underlying Ocular and Genetic Conditions.

Purpose: To report different biometric measurements in high myopia associated with different underlying ocular and genetic conditions. Design: Retrospective study. Subjects: Patients with high myopia. Methods: We searched the Stanford Research Repository tool to identify patients with the diagnosis of high myopia who were seen by a single provider at Byers Eye Institute at Stanford from January 2019 to March 2022. We performed a chart review and included eyes that had high myopia and ocular biometric measurements at any time point after January 2019. We divided our cohort into 5 different groups: (1) isolated high myopia (IHM) (control group); (2) retinopathy of prematurity (ROP); (3) familial exudative vitreoretinopathy; (4) Marfan syndrome; and (5) Stickler syndrome. Main Outcome Measures: Biometric measurements. Results: A total of 246 patients (432 eyes) were included as follows: 202 patients (359 eyes) in the IHM group, 17 patients (27 eyes) in the ROP group, 7 patients (12 eyes) in the familial exudative vitreoretinopathy group, 8 patients (14 eyes) in the Marfan group, and 12 patients (20 eyes) in the Stickler group. The ROP group showed significantly shorter axial lengths, shallower anterior chambers, and thicker lenses compared with the IHM group. The Marfan group showed significantly flatter corneas and thicker lenses compared with the IHM group. The Stickler group showed significantly longer axial lengths compared with the IHM group. Conclusions: High myopia is associated with variable biometric measurements according to underlying ocular or genetic conditions. Retinopathy of prematurity-associated high myopia is primarily lenticular, while Stickler syndrome-associated high myopia is axial. Marfan syndrome-associated high myopia is derived from both axial and lenticular mechanisms.

Analysis of the influencing factors of vault after the implantation of posterior chamber-phakic refractive lens for patients with super high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the influencing factors of vault after the posterior chamber phakic refractive lens(PC-PRL)implantation for patients with super high myopia.METHODS: Retrospective case study. A total of 40 patients with super high myopia(77 eyes)who underwent PC-PRL implantation in the Haixiang Eye Hospital from January 2019 to January 2021 were selected. They were followed up for at least 2a, postoperative anterior segment parameters, such as the uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), central anterior chamber depth(ACD), anterior chamber volume(ACV), anterior chamber angle(ACA), lens thickness and vault were evaluated, and then the influencing factors of postoperative vault were analyzed.RESULTS: The UCVA and BCVA of the patients significantly improved after PC-PRL implantation(P&#x003C;0.001). Average safety index(postoperative BCVA/preoperative BCVA)was 1.36±0.32, and average effective index(postoperative UCVA/preoperative BCVA)was 1.23±0.31 in 2a after surgery. The vault in 2a after surgery was correlated with preoperative ACD, ACV, ACA and lens thickness, and the preoperative ACV and lens thickness had significant impact on vault in 2a after surgery.CONCLUSIONS: The PC-PRL implantation is safe and effective in super high myopia, and it can significantly improve visual acuity. Furthermore, preoperative ACV and lens thickness are important influencing factors of postoperative vault.

Intralenticular Ozurdex injection in an eye with thicker lens and the therapeutic effect maintained for 15 months.

Introduction: To report a case of accidental intralenticular Ozurdex injection in an eye with thicker lens. During the follow-up period of 15 months, the therapeutic effect of intralenticular Ozurdex was maintained. Case description: Ozurdex was accidently injected into the lens of an eye with uveitis, and the lens thickness was measured to be 5.70 mm. The uveitis was under good control, and no significant development of cataract was observed until 7 months after the intralenticular Ozurdex injection. Then due to the outbreak of COVID-19, follow-up was suspended. Fifteen months after the injection, the patient returned to the doctor. At this time, significant cataract development was observed, whereas uveitis was still under good control. Accordingly, cataract surgery and Ozurdex extraction were performed. Two months after surgery, a mild recurrence of uveitis occurred. Conclusions: A thicker lens might be an important risk factor for accidental intralenticular Ozurdex injections. However, after intralenticular Ozurdex injection, the development of cataract was slow, and Ozurdex could still have a therapeutic effect on uveitis in this case. Thus, immediate surgery might be unnecessary for certain accidental intralenticular Ozurdex injection cases, and a follow-up strategy could be chosen to maintain the effect of Ozurdex.