OCT Biometry (B-OCT): A New Method for Measuring Ocular Axial Dimensions

Purpose. To present a new method of measuring ocular axial dimensions, termed OCT biometry (B-OCT). Design. Observational cross-sectional study and evaluation of new diagnostic technology. Methods. B-OCT was implemented in the spectral domain OCT device for posterior and anterior segment imaging (REVO NX, Optopol Technology). A total of 349 eyes (214 of healthy subjects, 115 of patients with cataract, and 20 with severe macular diseases) were enrolled in the study. The results of B-OCT were compared to swept source OCT-based IOLMaster 700 (Carl Zeiss Meditec). Differences in measurement values between the two biometers were determined using the paired t-test. Agreement was assessed through intraclass correlation coefﬁcients (ICCs) and Bland–Altman plots. Results. B-OCT obtained with REVO NX provides excellent interobserver reproducibility (ICC for: axial length (AXL) = 1.000; central corneal thickness (CCT) = 0.933; anterior chamber depth (ACD) = 0.933; lens thickness (LT) = 0.985) and intraobserver repeatability (ICC for: AXL = 1.000; CCT ≥ 0.994; ACD = 0.998; LT ≥ 0.993). The correlation between measurements made using both devices was outstanding (ICC for: AXL, healthy = 1.000; AXL, cataractous = 1.000; ACD, healthy = 0.998; ACD, cataractous = 0.997; LT, healthy = 0.998; LT, cataractous = 0.997; CCT, healthy = 0.989; CCT, cataractous = 0.979). The mean AXL measurement difference in healthy eyes was −0.001 ± 0.016 mm (the 95% LoA ranged from −0.034 to 0.031); mean ACD difference was 0.000 ± 0.024 mm (95% LoA, −0.047 to 0.047); mean LT difference was −0.002 ± 0.024 mm (95% LoA, −0.050 to 0.046); and mean CCT difference was −0.8 ± 5.1 μm (95% LoA, −10.81 to 9.26). The mean AXL measurement difference in cataractous eyes was −0.003 ± 0.022 mm (95% LoA, −0.046 to 0.039); mean ACD difference was 0.003 ± 0.029 mm (95% LoA, −0.054 to 0.059); mean LT difference was −0.002 ± 0.025 (95% LoA, −0.051 to 0.048); and mean CCT difference was 2.7 ± 6.4 μm (95% LoA, −9.80 to 15.7). Conclusion. The study shows small, nonsignificant differences between the biometric measurements obtained with REVO NX B-OCT and IOLMaster 700, which is of high significance for IOL power selection. As B-OCT utilizes a conventional OCT device, the measurements of the ocular axial dimensions are combined with high-resolution macular scans for the simultaneous assessment of central retina as a part of screening for macular pathology. The presented method is the first spectral domain OCT-based biometry technique and the only one integrated into a standard OCT device. Thus, it brings novel functionality to OCT technology.

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Comparison of Anterior Ocular Biometric Measurements Using Swept-Source and Time-Domain Optical Coherence Tomography

Journal of Ophthalmology ◽

10.1155/2020/9739878 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Sisi Chen ◽

Rongrong Gao ◽

Colm McAlinden ◽

Junming Ye ◽

Yiran Wang ◽

...

Keyword(s):

Time Domain ◽

Corneal Thickness ◽

Intraclass Correlation ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Correlation Coefficients ◽

Random Order ◽

Optical Coherence ◽

Swept Source ◽

Significant Difference

Purpose. To compare central corneal thickness (CCT), aqueous depth (AQD), and anterior chamber depth (ACD) measurements using the swept-source (CASIA SS-1000, Tomey, Japan) and time-domain (Visante, Carl Zeiss Meditec, USA) anterior segment optical coherence tomographers (OCT) in normal eyes. Methods. Sixty-eight eyes of 68 subjects were included. Three consecutive scans of each subject were obtained using both devices in a random order by one experienced operator. Standard deviation (Sw), coefficient of repeatability (CoR), coefficients of variation (CoV), and intraclass correlation coefficients (ICC) were used to evaluate the intraoperator repeatability. Agreement was assessed using the Bland–Altman plots and 95% limits of agreement (LoA). Results. All measurements of the swept-source OCT (SS-OCT) and time-domain OCT (TD-OCT) showed high repeatability with low CoR (CCT: 2.34 μm and 6.16 μm; AQD: 0.05 mm and 0.09 mm; ACD: 0.06 mm and 0.09 mm), low CoV (CCT: 0.16% and 0.42%; AQD: 0.61% and 0.97%; ACD: 0.53% and 0.83%), and high ICC (>0.98). The mean CCT with SS-OCT was slightly thicker than the results with TD-OCT (difference = 4.55 ± 2.62 μm, P<0.001). There was no statistically significant difference in AQD or ACD measurements between the two devices (0.01 ± 0.05 mm, P=0.111; 0.02 ± 0.05 mm, P=0.022, respectively). The 95% LoA between the SS-OCT and TD-OCT were −0.59 to 9.69 μm for CCT, −0.10 to 0.12 mm for AQD, and −0.09 to 0.12 mm for ACD. Conclusions. High levels of repeatability and agreement were found between the two devices for all three parameters, suggesting interchangeability. SS-OCT demonstrated superior repeatability compared with TD-OCT.

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Quantification of Trabecular-Iris Contact and its Prevalence by Optical Coherence Tomography in a Healthy Caucasian Population

European Journal of Ophthalmology ◽

10.5301/ejo.5000919 ◽

2016 ◽

Vol 27 (4) ◽

pp. 417-422 ◽

Cited By ~ 4

Author(s):

José Ignacio Fernández-Vigo ◽

Lucía De-Pablo-Gómez-De-Liaño ◽

Cristina Fernández-Vigo ◽

Inés Sánchez-Guillén ◽

Enrique Santos-Bueso ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Fourier Domain ◽

Optical Coherence ◽

Cross Sectional

Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

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Preoperative Anatomy Parameters in Implantable Collamer Lenses

10.21203/rs.3.rs-968382/v1 ◽

2021 ◽

Author(s):

Yanzhen Xue ◽

Yonghong Guo ◽

Ruibo Zhao

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Anterior Chamber ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Intraclass Correlation ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Case Series ◽

Significant Difference

Abstract Purpose: To determine patient preoperative anatomical features and the parameters of implantable collamer lenses (ICLs) relevant in explaining vault variability.Setting: Ophthalmology Xi’an Aier Gucheng Eye hospital , Xi’an China.Design: Retrospective case series.Methods:This study comprised 88 eyes of 45 patients implanted with myopic or toric ICLs between May 2021 and August 2021.Pentacam imaging was used for assessing white-to-white (WTW) diameter, central keratometry, anterior chamber depth(ACD), central corneal thickness and vault. Anterior-segment optical coherence tomography（AS-OCT） was used to measure the horizontal anterior chamber angle distance (ATA). Ultrasound biomicroscopy (UBM) was used to measure horizontal and vertical sulcus to sulcus(vSTS). According to different ACD,we divide ACD into shallow group(2.8 to 3.2 mm),medium group(3.2 to 3.5 mm),and deep group(＞3.5mm).Results: Linear regression analysis found significant correlation between WTW diameters and ATA diameters( y= 0.9605x+0.1491,R² = 0.9148),with a coefficient of determinant of 0.9148 (P＜0.01). Linear regression analysis found significant correlation between hSTS and vSTS（y=0.9855x-0.0178,R²=0.1979）,with a coefficient of determinant of 0.1979 (P＜0.01). WTW diameters showed statistically significant difference in shallow and medium ACD (t=-3.28,P＜0.01 ), significant difference in shallow and deep ACD (t=-4.69,P＜0.01 ),there was no correlation in medium and deep ACD(t=-1.41,P＞0.05 ). There was a statistically significant correlation between WTW diameters and hSTS diameters when the ACD was less than 3.5 mm (t=-0.451, P=0.000) (t=1.406, P=0.026),but weak correlation when the ACD was bigger than 3.5 mm(t=1.594, P=0.051). ATA and WTW with a mean difference close to zero(-0.66 mm). Despite the relatively high correlation (intraclass correlation co-efficient =0.689), the range of agreement is quite broad (1.33 mm).Conclusions:ATA measured with AS-OCT can not be used interchangeably with WTW obtained with Pentacam. WTW diameters and hSTS diameters have a statistically significant correlation when the ACD was less than 3.5 mm. WTW, ATA, hSTS and vSTS all should be considered during design the size of lens and regulating the vault after surgery.

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‘Van Herick Plus’: a modified grading scheme for the assessment of peripheral anterior chamber depth and angle

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2018-312132 ◽

2018 ◽

Vol 103 (7) ◽

pp. 960-965 ◽

Cited By ~ 3

Author(s):

Ramanjit Sihota ◽

Neha Kamble ◽

Ajay K Sharma ◽

Anju Bhari ◽

Amisha Gupta ◽

...

Keyword(s):

Anterior Chamber ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Area Under The Curve ◽

Weighted Kappa ◽

Accurate Method ◽

Cross Sectional ◽

Vertical Slit ◽

Inferior Angle

AimTo evaluate the accuracy of a new, modified grading scheme involving a short vertical slit beam, at the inferior angle for peripheral anterior chamber depth (PAC) and angle estimation and its correlation with anterior segment optical coherence tomography (ASOCT).MethodsA cross-sectional study of consecutive phakic patients, above 40 years of age, was performed. Using a short, vertical slit beam not reaching the pupil, the inferior angle at the sclerolimbal junction was evaluated, photographed and assessed by a ratio of peripheral anterior chamber depth to peripheral corneal thickness (PAC:PCT) and iridocorneal angle (ICA) on ImageJ software. The inferior angle at the same meridian was also recorded on ASOCT.ResultsBased on the PAC:PCT ratio, the subjects were divided into four groups: I (<1/4), II (1/4-1/2), III (>1/2–1) and IV (>1). The clinically assessed angle by short vertical slit beam correlated well with ASOCT values, trabecular-iris angle (TIA) (r=0.918; p<0.001) and scleral spur angle (r=0.903, p<0.001). The mean difference between ICA and TIA on ASOCT was 0.7970; 95% limits of agreement:−5.7670 to 7.3610 (±1.96 SD). For angles graded narrow on ASOCT (TIA <200), using a cut-off of peripheral PAC:PCT <1/4, the area under the curve was 0.918 with a sensitivity of 85.2% and a specificity of 88.2%. There was good agreement between ImageJ parameters with those assessed subjectively on photograph of the slit beam examination by a glaucoma fellow (weighted kappa=0.74) as compared with a general ophthalmologist, where there was moderate agreement (weighted kappa=0.57).ConclusionA short, vertical slit lamp beam evaluation at the inferior angle is an easy and relatively accurate method for both peripheral anterior chamber depth and angle assessment. It correlated well with ASOCT and can be used as a more reliable screening tool to identify eyes with possibly occludable angles.

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Distribution of Ocular Anterior and Posterior Segment Lengths Among a Cataract Surgical Population in Shanghai

Frontiers in Medicine ◽

10.3389/fmed.2021.688805 ◽

2021 ◽

Vol 8 ◽

Author(s):

Jiao Qi ◽

Wenwen He ◽

Jiaqi Meng ◽

Ling Wei ◽

Dongjin Qian ◽

...

Keyword(s):

Anterior Segment ◽

Anterior Chamber Depth ◽

Cross Sectional Study ◽

Posterior Segment ◽

Segment Length ◽

Cross Sectional ◽

Entire Study ◽

Study Population ◽

The Mean ◽

Male Subjects

Purpose: To investigate the distributions of the ocular anterior and posterior segment lengths among a cataract surgical population in Shanghai.Design: Cross-sectional study.Methods: Ocular biometric parameters of 23,462 eyes of 23,462 cataract surgery candidates were reviewed. Axial length (AL), anterior chamber depth (ACD), and lens thickness (LT) were obtained using IOL Master. Anterior segment length (ASL = ACD + LT), posterior segment length (PSL = AL – ASL) and the ratio of ASL to PSL (ASL/PSL) were calculated.Results: The mean ASL was 7.58 ± 0.39 mm, the mean PSL was 17.12 ± 2.64 mm. As the age grew, the ASL increased, and PSL increased firstly then decreased. Male subjects tended to have significantly longer ASL and shorter PSL than female subjects. With the increasing AL, the ASL was firstly decreased to trough at 20–22 mm AL group, then increased gradually, while the PSL increased rapidly. The ASL correlated positively with AL in normal, moderate and highly myopic eyes, negatively in short eyes. The PSL correlated positively with AL across the entire study population. The ASL/PSL was not constant in the eyes with different AL but had a relatively steep downward trend with the increasing AL in the short eyes, then decreased smoothly in normal, moderate and highly myopic eyes.Conclusions: In Chinese cataractous eyes, longer ASL and shorter PSL were associated with elder age and male gender. The change of ASL over AL was not linear, and the ASL was smallest in the eyes with AL of 20–22 mm. The elongation of the eyeball was mainly due to the extension of the posterior segment.

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Inter-Observer Reproducibility of Axial Ocular Measurements with Non-contact HAAG-STRAIT Biometer

Pakistan Journal of Ophthalmology ◽

10.36351/pjo.v37i3.1239 ◽

2021 ◽

Vol 37 (3) ◽

Author(s):

Muhammad Suhail Sarwar ◽

Sehrish Shahid ◽

Muhammad Arslan Ashraf ◽

Shaista Kanwal

Keyword(s):

Data Analysis ◽

Anterior Chamber ◽

Axial Length ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Excellent Correlation ◽

Interclass Correlation ◽

The Mean

Purpose: To check inter observer reproducibility of axial ocular measurements i.e. central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth (AD), lens thickness (LT), anterior segment lens (ASL), vitreous length (VL) and axial length (AL) with non-contact HAAG-STRAIT biometer. Study Design: Comparative Reproducibility Analysis. Place and Duration of Study: College of ophthalmology and allied vision sciences (COAVS), Mayo Hospital, Lahore. Methods: This study included 66 healthy students (132 eyes). Data was collected through self-designed proforma by 2 operators independently. SPSS 21 was used for data analysis. Interclass correlation was applied for agreement between the two readings. Interclass coefficient (ICC) value greater than 0.7 was considered as excellent correlation. Results: The mean CCT, AD, ACD, LT, ASL, VL, and AL were 526.47 ± 35.72 µm and 526.47 ± 36.06 µm (ICC = 0.92); 2.93 ± 0.29 mm and 2.93 ± 0.29 mm (ICC = 0.81); 3.45 ± 0.30 mm and 3.46 ± 0.30 mm (ICC = 0.79); 3.58 ± 0.28 mm and 3.56 ± 0.22 mm (ICC = 0.76); 7.03 ± 0.30 mm and 7.02 ± 0.27 mm (ICC = 0.80); 16.56 ± 0.85 mm and 16.62 ± 0.81 mm (ICC = 0.72); and 23.59 ± 0.85 mm and 23.64 ± 0.87 mm (ICC: 0.76) of observer 1 and 2, respectively. Conclusion: Non-contact Biometer (HAAG-STRAIT) has high inter-observer reproducibility with strong interclass coefficient of greater than 0.72. Key Words: Biometry, Axial Length, Central Corneal Thickness, Anterior Chamber Depth.

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Morphometric evaluation and measurements of primary pterygium by anterior segment optical coherence tomography and its relation with astigmatism

Therapeutic Advances in Ophthalmology ◽

10.1177/25158414211020145 ◽

2021 ◽

Vol 13 ◽

pp. 251584142110201

Author(s):

Anuradha Raj ◽

Renu Dhasmana ◽

Harsh Bahadur

Keyword(s):

Optical Coherence Tomography ◽

Corneal Thickness ◽

Anterior Segment ◽

Cross Sectional Study ◽

Optical Coherence ◽

Cross Sectional ◽

Horizontal Length ◽

The Mean ◽

The Relationship ◽

Primary Pterygium

Purpose: To evaluate the relationship between measurements and various morphometric parameters of primary pterygium on anterior segment optical coherence tomography(AS-OCT) and refractive and keratometric astigmatism. Methods: In this cross-sectional study, patients with primary pterygium were included. The AS-OCT parameters of pterygium consisting of epithelial thickness near apex(µm), apical or head thickness(µm), its thickness at limbus(µm), horizontal length of pterygium(mm), central corneal thickness (µm) and maximum pterygium thickness(mm) were evaluated. Results: Sixty three patients comprising of 63 eyes with a primary pterygium were studied. The mean keratometric and refractive astigmatism were 1.69 ± 3.15 Diopter(D) and0.5 ± 1.4D, respectively. There was a significant association between pterygium grade and stocker’s line with keratometric astigmatism ( p = 0.02, 0.00) respectively. Vertical and horizontal length on slit lamp and horizontal length on AS-OCT showed significant association with keratometric astigmatism ( p = 0.05, 0.00,0.00), respectively. Limbal thickness on AS-OCT showed significant positive correlation with refractive astigmatism ( r = 0.29, p = 0.02). Conclusion: The pterygium grade influences the keratometric astigmatism. Increased limbal thickness of pterygium on AS-OCT leads to more refractive astigmatism.

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Comparison between a New Optical Biometry Device and an Anterior Segment Optical Coherence Tomographer for Measuring Central Corneal Thickness and Anterior Chamber Depth

Journal of Ophthalmology ◽

10.1155/2016/6347236 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5

Author(s):

Jinhai Huang ◽

Weicong Lu ◽

Giacomo Savini ◽

Hao Chen ◽

Chengfang Wang ◽

...

Keyword(s):

Anterior Chamber ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Normal Subjects ◽

Optical Coherence ◽

Limits Of Agreement ◽

Mean Values ◽

The Mean

Purpose.To compare between a new optical biometer (AL-Scan, Nidek Co., Aichi, Japan) and an anterior segment optical coherence tomographer (Visante AS-OCT, Carl Zeiss Meditec, Dublin, USA) for measuring central corneal thickness (CCT), anterior chamber depth (ACD), and aqueous depth (AD).Methods.Sixty-three eyes of 63 normal subjects were examined with AL-Scan and Visante AS-OCT in this prospective study. One eye per subject was measured three times with both devices to record their CCT, ACD, and AD. All procedures were performed by the same operator. Agreement between the two devices was assessed using pairedt-tests, Bland-Altman plots, and 95% limits of agreement (LoA).Results.The mean CCT, ACD, and AD measured by AL-Scan were538.59±27.37 μm,3.70±0.30 mm, and3.16±0.30 mm, respectively. The mean values obtained by the Visante OCT were536.14±26.61 μm for CCT,3.71±0.29 mm for ACD, and3.17±0.29 mm for AD. The mean CCT by the AL-Scan was higher than that obtained by the Visante AS-OCT (difference =2.45±6.07 μm,P<0.05). The differences in ACD and AD measurements were not statistically significant. The 95% LoA of CCT, ACD, and AD were between −9.44 and 14.35 μm, −0.15 and 0.12 mm, and −0.15 and 0.12 mm, respectively.Conclusions.Since these two devices were comparable for measuring CCT, ACD, and AD, their results can be interchangeably used in the clinic.

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The corneal effects of intravitreal dexamethasone implantation

Therapeutic Advances in Ophthalmology ◽

10.1177/2515841420947544 ◽

2020 ◽

Vol 12 ◽

pp. 251584142094754

Author(s):

Alper Halil Bayat ◽

Gamze Karataş ◽

Muhammet Mustafa Kurt ◽

Mustafa Nuri Elçioğlu

Keyword(s):

Endothelial Cell ◽

Cell Structure ◽

Glycosylated Hemoglobin ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Corneal Topography ◽

Specular Microscopy ◽

The Mean ◽

Intravitreal Dexamethasone

Objectives: To evaluate the corneal effects of the intravitreal dexamethasone implantation using corneal topography and specular microscopy. Material and methods: 27 eyes of the 27 patients who received a single intravitreal dexamethasone implantation dose for diabetic macular edema were enrolled in this study. Sirius topography and EM-3000 specular microscopic examinations were performed at the initial examination (baseline), and then on the first day, during the first week, and 1 month after IDI. Changes in corneal parameters were investigated. Results: The mean age was 58.66 ± 6.59 years. 15 patients were men, and 12 were women. The mean disease duration was 12.2 ± 2.4 months, and mean glycosylated hemoglobin (HbA1c) was 7.2 ± 1.1. After dexamethasone injection, the mean central corneal thickness, endothelial cell density, and coefficient variation of cell area presented a statistically significant decrease ( p < 0.05). Anterior segment parameters, such as anterior chamber depth, iridocorneal angle, sim K1 and K2 keratometry, pupillary diameter, horizontal visible iris diameter, and corneal astigmatism did not change ( p > 0.05). Conclusion: Intravitreal dexamethasone implantation affects corneal endothelial cell structure but does not appear to affect corneal topography parameters.

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Refractive error and biometrics of anterior segment of eyes of healthy young university students in Japan

Scientific Reports ◽

10.1038/s41598-019-51920-4 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Kumiko Kato ◽

Mineo Kondo ◽

Maki Takeuchi ◽

Koji Hirano

Keyword(s):

University Students ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Japanese University ◽

The Mean ◽

Corneal Diameter

Abstract To determine the parameters of the anterior segment of eyes that are significantly associated with the refractive error in healthy young Japanese university students. This was a cross-sectional observational study of 229 healthy Japanese university students (men: women,147:82) whose age ranged between 20 to 29 years. Univariate and multivariate linear regression analyses were performed to identify the factors that were significantly correlated with the refractive error. The independent variables included age, sex, axial length, anterior chamber depth, corneal diameter, curvature of anterior surface of cornea, and central corneal thickness. The mean refractive error (spherical equivalent) was −4.1 ± 2.7 diopters (D) with a range of −12.5 to +0.5 D, and the mean axial length was 25.4 ± 1.3 mm with a range of 22.4 to 29.0 mm. Pearson univariate correlation analysis found that the refractive error was significantly and negatively correlated with the axial length (R = −0.82, P < 0.001), deeper anterior chamber (R = −0.30, P < 0.001), and larger corneal diameter (R = −0.21, P = 0.001). Multiple regression analysis showed that the refractive error was significantly associated with a longer axial length (P < 0.001), a deeper anterior chamber (P < 0.001), and a flatter corneal curvature (P < 0.001).The biometric values of the anterior segment of the eyes should make the eye more hyperopic which would reduce the myopia-inducing lengthening of the axial length.

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