Axial Length and White to White Corneal Diameter in Eyes with Keratoconus

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Omnia Talaat Abd elwahab ◽  
Dina Ezzat Mansour ◽  
Maged Maher Salib Roshdy ◽  
Ahmed Taha Ismail ◽  
Omnia Talaat Abd elwahab
Keyword(s):  
Axial Length ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Normal Group ◽  
Control Group ◽  
Spherical Equivalent ◽  
Lens Thickness ◽  
Significant Difference ◽  
The Mean ◽  
Corneal Diameter

Abstract Objective To study the axial length (AL) and white to white (WTW) corneal diameter in keratoconus (KC) eyes and compare them to normal eyes. Methods Sixty-three eyes of 53 patients were included in this cross-sectional observational study divided into KC group comprised of 28 eyes of 18 patients and control group comprised of 35 eyes of 35 patients based on clinical and tomographic findings. All subjects were examined using rotating Scheimpflug corneal tomography (Pentacam HR; Oculyzer II) for central corneal thickness (CCT), thinnest corneal thickness (TCT), keratometric values, anterior chamber depth (ACD) and lens thickness, and by optical biometry (IOLMaster 500) for axial length (AL) measurements. Vitreous cavity length (VCL) was calculated by subtracting the values of CCT, ACD (internal), and lens thickness from the AL. White to white (WTW) corneal diameter was measured using Placido-based tomography (Topolyzer VARIO). Results The mean age was 31.27±8.65 years(30.39 ± 9.31) in the KC group and .(31.74 ± 8.38) in the non KC group. The KC group included 28 eyes their mean spherical equivalent (SE) was -3.16 ± 2.42 and the control group 35 healthy eyes including 23 ametropic eyes with mean spherical equivalent (SE) (-3.95±4.50 D) and 12 emmetropic eyes with mean SE (-0.19±0.40 D). The mean VCL was significantly greater in normal eyes (17.45 ±1.34 mm) compared with KC (16.77±1.18 mm) (P = 0.037), while the mean ACD (internal) was significantly greater in KC eyes compared to normal (P = 0.020) and the lens thickness showed no statistically significant difference. The greater VCL in the normal group was compensated by the greater ACD in the KC group causing the total AL to have no statistically significant difference (normal eyes =24.44 ±1.38 mm and KC eyes= 24.21 ±1.31 mm) (P = 0.513). There was no statistically significant difference in the WTW corneal diameter between KC and normal eyes (11.81 ±0.35 mm in the normal group compared to 11.79 ±0.35 mm in the KC group) (P = 0.835). Conclusion VCL was significantly greater in normal eyes compared with those eyes with KC. AL and WTW showed no difference between the two groups.

scholarly journals Presbyopia and its anatomical and physiological variants

1970 ◽  
Vol 3 (2) ◽  
pp. 155-158
Author(s):  
M Gupta ◽  
RR Sukul ◽  
Y Gupta ◽  
M Dey ◽  
A Phougat ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Axial Length ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Physiological Parameters ◽  
Corneal Curvature ◽  
Lens Thickness ◽  
Significant Difference ◽  
The Mean

Aim: To study the various ocular anatomical and physiological parameters in presbyopia. Materials and methods: We studied the various ocular anatomical and physiological parameters like corneal curvature (keratometry readings: K1 and K2), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and axial length (AL) in 100 presbyopic patients between 35 - 55 years of age. The patients were divided into two age groups: I (35 – 44 years) and II (45-55 yrs). ACD, AL and LT were measured using an Ascan. CCT was measured with ultrasonic pachymetry. Results: The CCT decreased (BE), LT increased and ACD decreased (RE) significantly with increasing age (p < 0.05). There was no significant difference in males and females. Nearly 3/4th of the total increase in lens thickness was responsible for the decrease in the anterior chamber depth and the rest, 1/4th , goes posteriorly. Corneal curvature and AL showed no significant change with age. Conclusions: The mean of CCT decreased significantly with advancing age. As age increased, the mean value of lens thickness increased and anterior chamber depth decreased. Nearly 3/ 4th of total increase in LT was anteriorly, decreasing the ACD. Corneal curvature and AL has no relation with age. Key words: Presbyopia, central corneal thickness, anterior chamber depth, lens thickness, axial length DOI: http://dx.doi.org/10.3126/nepjoph.v3i2.5269 Nepal J Ophthalmol 2011; 3(2): 155-158

Topical atropine in retarding myopia progression and axial length growth in children with myopia

2020 ◽  
Vol 13 (4) ◽  
pp. 111-114
Author(s):  
Abdur Rahman Mohammad Alam ◽  
Md. Sanwar Hossain ◽  
Md. Shafiqul Islam
Keyword(s):  
Axial Length ◽  
Control Group ◽  
Refractive Errors ◽  
Spherical Equivalent ◽  
Myopia Progression ◽  
Length Growth ◽  
Significant Difference ◽  
The Mean ◽  
And Control

This study was conducted to observe the effect of atropine in retarding myopia progression and axial length growth in 36 myopic children (atropine group, 24; control, 12). The initial spherical equivalent of the atropine group and control group was -3.0 ± 1.6 dioptre and -3.5 ± 1.6 dioptre respectively. At the 12th month in atropine group, it was -2.9 ± 2.6 dioptre and -4.6 ± 1.9 dioptre in the control group. The power of the atropine group reduced but rose in the control group after 12 months. There was a statistically significant difference in final refractive errors between the two groups (p<0.05). The initial axial length of the atropine group and control group was 24.3± 1.0 mm and 24.6 ± 1.1 mm respectively. In 12th month, the changes in axial length in the two groups was insignificant. However, the mean axial length progression at 12 months of the atropine group was -0.1 ± 0.1 mm and it was lower than the control group which was -0.2 ± 0.2 mm, and this was statistically significant (p<0.05). In conclusion, topical atropine (0.01%) retarded myopia progre-ssion and axial length growth in myopic children.    

scholarly journals Evaluation of Anterior Segment’s Structures in Tilted Disc Syndrome

2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Ercan Ozsoy ◽  
Abuzer Gunduz ◽  
Ersin Ersan Demirel ◽  
Tongabay Cumurcu
Keyword(s):  
Anterior Chamber ◽  
Axial Length ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Control Group ◽  
Tilted Disc Syndrome ◽  
Chamber Volume ◽  
Significant Difference ◽  
Tilted Disc

Purpose. To evaluate anterior segment’s structures by Pentacam in patients with tilted disc syndrome (TDS).Methods. Group 1 included forty-six eyes of forty-six patients who have the TDS. Group 2 including forty-six eyes of forty-six cases was the control group which was equal to the study group in age, gender, and refraction. A complete ophthalmic examination was performed in both groups. All cases were evaluated by Pentacam. The axial length (AL) of eyes was measured by ultrasound. Quantitative data obtained from these measurements were compared between two groups.Results. There was no statistically significant difference for age, gender, axial length, and spherical equivalent measurements between two groups (p=0.625,p=0.830,p=0.234, andp=0.850). There was a statistically significant difference for central corneal thickness (CCT), corneal volume (CV), anterior chamber angle (ACA), and pupil size measurements between two groups (p=0.001,p=0.0001,p=0.003, andp=0.001). Also, there was no statistically significant difference for anterior chamber depth (ACD), anterior chamber volume (ACV), and lens thickness (LT) measurements between two groups (p=0.130,p=0.910, andp=0.057).Conclusion. We determined that CCT was thinner, CV was less, and ACA was narrower in patients with TDS. There are some changes in the anterior segment of the eyes with tilted disc.

scholarly journals The Study of Ocular Parameters in Low to Moderate Myopic Chinese Children Age Between Eight to Eighteen-Year-Old

2021 ◽  
Author(s):  
Zhengxuan Li ◽  
Lu Sun ◽  
Hongxin Song
Keyword(s):  
Retrospective Study ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Corneal Endothelial Cell ◽  
Spherical Equivalent ◽  
Corneal Endothelial Cell Density ◽  
The Mean ◽  
Beijing China ◽  
Corneal Diameter

Abstract Purpose: The primary aim of this study was to analyze the distribution of ocular parameters of children aged from eight to eighteen-year-old with low to moderate myopia as well as offer useful information for the design and clinical fitting of ortho-k lens in China.Methods: In this retrospective study, we collected data of 300 subjects (600 eyes) age between eight to eighteen-year-old from the myopic control outpatient clinic at Beijing Tongren Hospital, Beijing, China. The spherical equivalent (SE), axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), corneal endothelial cell density (CECD)，corneal diameter (CD), simulated K (Sim K) were collected from all the subjects and analyzed. Results: The mean of SE for all subjects was -3.12 ± 1.21D, the median was -3.16D. The mean of AL for all subjects was 24.72 ± 0.83 mm, the median was 24.72 mm. The mean of CCT for all subjects was 537.8 ± 29.82 μm, the median was 538.17 μm. The mean of CECD for all subjects was 3340.3 ± 352.6 cells/mm2, the median was 3357.77 cells/mm2. The mean of ACD for all subjects was 3.71 ± 0.21 mm, the median was 3.69 mm. The mean of CD for all subjects was 12.15 ± 1.67 mm, the median was 12.05 mm. The mean of flat K was 42.80 ± 1.29, the median was 42.81. The mean of steep K was 43.76 ± 1.37, the median was 43.76.Conclusions: This study provided the distribution of ocular parameters to offer useful information for diagnosis of many eye conditions. Meanwhile, the distribution of ocular parameters of children aged from eight to eighteen-year-old with low to moderate myopia is beneficial to make the application of overnight orthokeratology lens more appropriate and effective.

Evaluation of biometric parameters in phacomorphic glaucoma and mature cataracts

2020 ◽  
pp. 112067212091453
Author(s):  
Ali Keleş ◽  
Emine Şen ◽  
Ufuk Elgin
Keyword(s):  
Anterior Chamber ◽  
Axial Length ◽  
Odds Ratio ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Mature Cataract ◽  
Biometric Parameters ◽  
Significant Difference ◽  
The Mean

Purpose: The aims of this study were to compare the biometric parameters and axial lengths of eyes with phacomorphic glaucoma and mature cataract and to identify differences that might predispose to development of phacomorphic glaucoma. Methods: Three hundred forty-two patients were enrolled in this retrospective study. The eyes were divided into four groups—Group (G)1: phacomorphic glaucoma ( n = 29), G2: mature cataract ( n = 313), G3: contralateral phacomorphic glaucoma ( n = 29), and G4: contralateral mature cataract ( n = 313). Central corneal thickness and anterior chamber depth were assessed by optical low-coherence reflectometry (Lenstar LS 900®; Haag-Streit AG, Switzerland), while axial length was determined by A-scan ultrasound biometry. Results: The mean central corneal thickness of G1 was significantly higher than in other groups ( p < 0.001) and the mean anterior chamber depth of G1 was the lowest among the groups ( p < 0.001). Also, G2 had lower mean anterior chamber depth than G4 ( p < 0.001) and G3 had lower mean anterior chamber depth than G4 ( p = 0.007). Anterior chamber depth less than 3.27 mm had the higher odds ratio for distinguishing G3 versus G4 (odds ratio = 10.79, p < 0.001). Furthermore, patients aged ⩾68.9 years had the higher odds ratio for distinguishing G1 versus G2 (odds ratio = 2.82, p = 0.019). There was no significant difference in the presence of pseudoexfoliation material between G1 and G2 ( p = 0.057). There were no significant differences in axial length values among the four groups ( p = 0.097). Conclusion: Advanced age and shallow anterior chamber depth were found to be risk factors for developing phacomorphic glaucoma, but the presence of pseudoexfoliation material was not found to play a role as a risk factor in phacomorphic glaucoma development.

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

2019 ◽  
Vol 9 (1) ◽  
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.

scholarly journals Comparing biometry in normal eyes of children with unilateral cataract/corneal disease to age-matched controls

2016 ◽  
Vol 7 (2) ◽  
pp. 108-116
Author(s):  
Adem Gul ◽  
Adnan Cinal ◽  
Cagatay Caglar ◽  
Tekin Yasar ◽  
Adil Kilic
Keyword(s):  
Anterior Chamber ◽  
Axial Length ◽  
Central Corneal Thickness ◽  
Pediatric Patients ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Control Group ◽  
Study Group ◽  
Lens Thickness ◽  
The Difference

Objective: To compare ocular biometry and central corneal thickness of unaffected healthy eyes of pediatric patients with monocular cataracts/corneal opacities and age- matched controls.Materials and methods: We studied 329 eyes of 329 children who were between 1 and 12 years old. The study group (n: 164) consisted of healthy fellow eyes of children operated for unilateral congenital/traumatic cataract and corneal laceration. Axial length, anterior chamber depth, lens thickness, vitreous chamber depth, and central corneal thickness were measured by ultrasound biometry/ pachymetry. Results: Axial length was 22.16 mm in the study group and 21.99 mm in the control group. Anterior chamber depth, lens thickness, and vitreous chamber depth results were 3.35; 3.64 and 15.20 in the treatment group and 3.20; 3.63, and 15.15 mm in the control group, respectively. The axial length and all the components, i.e. anterior chamber depth, lens thickness, and vitreous chamber depth are higher in the unaffected healthy eyes of the pediatric patients than that of the control group but only the difference in the anterior chamber depth was statistically significant. The central corneal thickness was 548 microns and 559 microns in the study and the control groups, respectively, and the difference was found to be significant. Conclusion: Greater anterior chamber depth was chiefly responsible for the overall increase in the axial length in the study group. The central corneal thickness was significantly thinner in the study group than that of the control group. 

scholarly journals Corneal Biomechanical Parameters and Central Corneal Thickness in Glaucoma Patients, Glaucoma Suspects, and a Healthy Population

2021 ◽  
Vol 10 (12) ◽  
pp. 2637
Author(s):  
Mª. Ángeles del Buey-Sayas ◽  
Elena Lanchares-Sancho ◽  
Pilar Campins-Falcó ◽  
María Dolores Pinazo-Durán ◽  
Cristina Peris-Martínez
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Mean Difference ◽  
The Other ◽  
Control Group ◽  
Healthy Population ◽  
Diagnostic Categories ◽  
Significant Difference ◽  
Biomechanical Parameters ◽  
The Mean

Purpose: To evaluate and compare corneal hysteresis (CH), corneal resistance factor (CRF), and central corneal thickness (CCT), measurements were taken between a healthy population (controls), patients diagnosed with glaucoma (DG), and glaucoma suspect patients due to ocular hypertension (OHT), family history of glaucoma (FHG), or glaucoma-like optic discs (GLD). Additionally, Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated IOP (IOPcc) were compared between the different groups of patients. Methods: In this prospective analytical-observational study, a total of 1065 patients (one eye of each) were recruited to undergo Ocular Response Analyzer (ORA) testing, ultrasound pachymetry, and clinical examination. Corneal biomechanical parameters (CH, CRF), CCT, IOPg, and IOPcc were measured in the control group (n = 574) and the other groups: DG (n = 147), FHG (n = 78), GLD (n = 90), and OHT (n = 176). We performed a variance analysis (ANOVA) for all the dependent variables according to the different diagnostic categories with multiple comparisons to identify the differences between the diagnostic categories, deeming p < 0.05 as statistically significant. Results: The mean CH in the DG group (9.69 mmHg) was significantly lower compared to controls (10.75 mmHg; mean difference 1.05, p < 0.001), FHG (10.70 mmHg; mean difference 1.00, p < 0.05), GLD (10.63 mmHg; mean difference 0.93, p < 0.05) and OHT (10.54 mmHg; mean difference 0.84, p < 0.05). No glaucoma suspects (FHG, GLD, OHT groups) presented significant differences between themselves and the control group (p = 1.00). No statistically significant differences were found in the mean CRF between DG (11.18 mmHg) and the control group (10.75 mmHg; mean difference 0.42, p = 0.40). The FHG and OHT groups showed significantly higher mean CRF values (12.32 and 12.41 mmHg, respectively) than the DG group (11.18 mmHg), with mean differences of 1.13 (p < 0.05) and 1.22 (p < 0.001), respectively. No statistically significant differences were found in CCT in the analysis between DG (562 μ) and the other groups (control = 556 μ, FHG = 576 μ, GLD = 569 μ, OHT = 570 μ). The means of IOPg and IOPcc values were higher in the DG patient and suspect groups than in the control group, with statistically significant differences in all groups (p < 0.001). Conclusion: This study presents corneal biomechanical values (CH, CRF), CCT, IOPg, and IOPcc for diagnosed glaucoma patients, three suspected glaucoma groups, and a healthy population, using the ORA. Mean CH values were markedly lower in the DG group (diagnosed with glaucoma damage) compared to the other groups. No significant difference was found in CCT between the DG and control groups. Unexpectedly, CRF showed higher values in all groups than in the control group, but the difference was only statistically significant in the suspect groups (FHG, GLD, and OHT), not in the DG group.

scholarly journals Evaluation of Anterior Chamber Depth in 28,709 Adult Cataract Patients in China using Swept-Source Optical Biometry

2021 ◽  
Author(s):  
Qiong Lei ◽  
Haixia Tu ◽  
Xi Feng ◽  
Yong Wang
Keyword(s):  
Cataract Surgery ◽  
Anterior Chamber ◽  
Axial Length ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Multivariate Regression Analysis ◽  
Swept Source ◽  
Mean Values ◽  
The Mean ◽  
Cataract Patients

Abstract Background: To create an anterior chamber depth (ACD) regression model for adult cataract surgery candidates from China, and to evaluate the distribution of their ocular biometric parameters.Methods: The ocular biometric records of 28,709 right eyes of cataract surgery candidates who were treated at Aier Eye Hospitals in nine cities from 2018 to 2019 were retrospectively analyzed. All measurements were taken with IOLMaster 700. We included patients who were at least 40 years old and were diagnosed with cataract.Results: The mean age of the patients was 68.6 ± 11.0 years. The mean values recorded were as follows: axial length (AL), 24.17 ± 2.47 mm; mean keratometry (Km) value, 44.09 ± 3.25 D; corneal astigmatism (CA), 1.06 ± 0.98 D; ACD, 3.02 ± 0.45 mm; lens thickness (LT), 4.52 ± 0.45 mm; central corneal thickness (CCT), 0.534 ± 0.04 mm; and white to white (WTW) corneal diameter, 11.64 ± 0.46 mm. The proportion of patients with long axial length (AL >25 mm) decreased with age. ACD, LT, AL, Km, WTW, and age were correlated. In the multivariate regression analysis of ACD, which included LT, AL, WTW, sex, Km, CCT, and age, there was a reasonable prediction with adjusted R2 = 0.629.Conclusions: The results show that high myopes are inclined to schedule cataract surgery at a younger age. LT and AL were found to be important factors that affect ACD. This study provides reference data for cataract patients from China.

scholarly journals A calculator proposal for estimating refractive error after 3 years using the onset biometric values in primary school children: a cohort study

2021 ◽  
Author(s):  
Feride Tuncer Orhan ◽  
Haluk Huseyin Gürsoy
Keyword(s):  
Primary School ◽  
Anterior Chamber ◽  
Refractive Error ◽  
Axial Length ◽  
Anterior Chamber Depth ◽  
Primary School Children ◽  
Optical Parameters ◽  
Spherical Equivalent ◽  
Final Data ◽  
The Mean

Aim To evaluate consecutive measurements of the biometric parameters, age, and refraction error in a Turkish population at primary school age. Materials and Methods A total of 197 children aged between 7-12 years were included. The data of three consecutive measurements of children, who were examined at least once a year for three years using both cycloplegic auto-refractometry and optical biometry, were used in this retrospective study. Spherical equivalent <-0.50D was considered to be myopic; >+0.75D was considered to be hypermetropic. Age, gender, body mass index, spherical equivalent, axial length, anterior chamber depth, central corneal thickness, keratometry, and lens thickness were analyzed. The onset data obtained in 2013 whereas, the final data were from 2015. Logistic and Cox regression analyses were performed (p<0.05). Results The mean of the onset and the final spherical equivalents were 0.19D (0.56), and 0.08D (0.80), respectively. The myopia prevalence was increased among refractive errors in observation periods (univariable analysis p=0.029; multivariable analysis p=0.017). The onset axial length (HR:4.55, 95%CI:2.87-7.24, p<0.001), keratometry (HR:2.04, 95%CI:1.55-2.67, p<0.001) and age (HR:0.73, 95%CI: 0.57-0.92, p=0.009) correlated myopia progression. To calculate the estimated spherical equivalent, the onset data were included in the logistic regression model. The onset data of spherical equivalent (β=0.916, p<0.001), axial length (β=-0.451, p<0.001), anterior chamber depth (β=0.430, p=0.005) and keratometry (β=-0.172, p<0.001) were found to be significantly associated with the mean SE at the final data. Conclusions To calculate the estimated spherical equivalent following three years, an equation was proposed. The estimated refractive error of children can be calculated by using the proposed equation with the associated onset optical parameters.

Sign in / Sign up

Export Citation Format

Share Document