Lamina cribrosa thickness is not correlated with central corneal thickness or axial length in healthy eyes

2012 ◽  
Vol 251 (3) ◽  
pp. 847-854 ◽  
Author(s):  
Eun Ji Lee ◽  
Tae-Woo Kim ◽  
Robert N. Weinreb ◽  
Min Hee Suh ◽  
Hyunjoong Kim
Keyword(s):  
Axial Length ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Lamina Cribrosa ◽  
Lamina Cribrosa Thickness ◽  
Healthy Eyes

Evaluation of the B/F Ratio Distribution of Cataract Patients Without Corneal Abnormalities and Its Effect on Ocular Parameters

2021 ◽  
Vol 44 (4) ◽  
pp. E46-54
Author(s):  
Michael Deng ◽  
Lina Lan ◽  
Tianhui Chen ◽  
Min Zhang ◽  
Jiahui Chen ◽  
...  
Keyword(s):  
Axial Length ◽  
Central Corneal Thickness ◽  
Spherical Aberration ◽  
Linear Regression Analysis ◽  
Corneal Thickness ◽  
Curvature Radius ◽  
Multivariate Linear Regression Analysis ◽  
Corneal Surface ◽  
Ratio Distribution ◽  
Corneal Radius

Purpose: To evaluate the distribution of the posterior-anterior corneal radius ratio (B/F ratio; posterior corneal radius/anterior corneal radius) in patients without corneal abnormalities, and to investigate which parameters affect this ratio. Methods: Five thousand eyes from 5,000 patients who underwent cataract surgery were recruited to this study. We explored the linear relationship between B/F ratio and 13 variables using Principal Component-Multivariate Linear Regression Analysis. Results: The B/F ratio was negatively correlated with the difference between simulated keratometry (SimK) and true net power (TNP), central corneal thickness, spherical aberration (SA), and posterior corneal astigmatism and positively correlated with posterior corneal radius, corneal posterior surface, axial length (AL) and anterior corneal radius. Several variables (central corneal thickness, difference between SimK and TNP and asphericity coefficient (Q-value) of the posterior corneal surface) had the highest loading on the final score. B/F ratio reflects the refractive state and anatomical structure of the cornea: thus, higher B/F ratios were associated with larger posterior corneal surface curvature radius, longer axial length, thinner central corneal thickness, lower high order aberrations of the cornea and SA, and the numerical difference between simK and TNP gradually reduced. In clinical practice, for patients with lower B/F ratio, special care should be taken in the choice of system used for intraocular lens (IOL) measurements.

scholarly journals Effects of SMILE Surgery on Intraocular Pressure, Central Corneal Thickness, Axial Length, Peripapillary Retinal Nerve Fiber Layer, and Macular Ganglion Cell Complex Thickness

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Zhanlin Zhao ◽  
Sylvain Michée ◽  
Jean-François Faure ◽  
Christophe Baudouin ◽  
Antoine Labbé
Keyword(s):  
Intraocular Pressure ◽  
Ganglion Cell ◽  
Nerve Fiber ◽  
Axial Length ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Ganglion Cell Complex ◽  
Fiber Layer ◽  
Rnfl Thickness ◽  
The Mean

Purpose. To evaluate the change in intraocular pressure (IOP), central corneal thickness (CCT), axial length, peripapillary retinal nerve fiber layer (RNFL) thickness, and macular ganglion cell complex (GCC) thickness after small incision lenticule extraction (SMILE) surgery. Methods. This prospective observational study was conducted in Espace Nouvelle Vision, Ophthalmological Clinic, Paris, France. Fifty eyes of 25 patients were enrolled in this study and underwent SMILE surgeries. IOP, central corneal thickness (CCT), axial length (AL), peripapillary RNFL thickness, and macular GCC thickness were measured before and at 3 months after SMILE. Results. The mean preoperative spherical equivalent was −3.15 ± 1.50 diopters (D), and the mean postoperative value was 0.15 ± 0.28 D. After SMILE surgery, IOP decreased from 15.03 ± 2.79 mmHg to 11.02 ± 2.73 mmHg and 10.02 ± 2.21 mmHg at 1 and 3 months, respectively ( P < 0.01 for both comparisons). The mean decrease in measured IOP as a function of ablation depth was 0.065 ± 0.031 mmHg/μm. CCT decreased from 545.98 ± 26.61 μm to 478.40 ± 30.26 μm after SMILE surgery ( P < 0.01 ). AL decreased from 24.80 ± 0.84 mm to 24.70 ± 0.83 mm ( P < 0.01 ). There was no statistically significant change in mean peripapillary RNFL or mean GCC thickness after SMILE surgery. Conclusions. SMILE surgery modified IOP measurement, CCT, and AL but did not change peripapillary RNFL and macular GCC thicknesses. The postoperative drop in measured IOP might be explained by the decreased CCT. An accurate re-evaluation of AL should be performed before cataract surgery among post-SMILE patients.

scholarly journals Reproducibility and repeatability of central corneal thickness measurement in healthy eyes using four different optical devices

2016 ◽  
Vol 37 (4) ◽  
pp. 1039-1045 ◽  
Author(s):  
Remzi Karadag ◽  
Murat Unluzeybek ◽  
Ozgur Cakici ◽  
Ayse Yagmur Kanra ◽  
Huseyin Bayramlar
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Optical Devices ◽  
Thickness Measurement ◽  
Healthy Eyes

scholarly journals Repeatability and Agreement of Central Corneal Thickness and Keratometry Measurements between Four Different Devices

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Laszlo Kiraly ◽  
Jana Stange ◽  
Kathleen S. Kunert ◽  
Saadettin Sel
Keyword(s):  
Clinical Practice ◽  
Statistical Analysis ◽  
Correlation Coefficient ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Bland Altman Method ◽  
Significant Difference ◽  
Healthy Eyes ◽  
Iolmaster 700

Background.To estimate repeatability and comparability of central corneal thickness (CCT) and keratometry measurements obtained by four different devices in healthy eyes.Methods.Fifty-five healthy eyes from 55 volunteers were enrolled in this study. CCT (IOLMaster 700, Pentacam HR, and Cirrus HD-OCT) and keratometry readings (IOLMaster 700, Pentacam HR, and iDesign) were measured. For statistical analysis, the corneal spherocylinder was converted into power vectors (J0, J45). Repeatability was assessed by intraclass correlation coefficient (ICC). Agreement of measurements between the devices was evaluated by the Bland-Altman method.Results.The analysis of repeatability of CCT data of IOLMaster 700, Pentacam HR, and Cirrus HD-OCT showed high ICCs (range 0.995 to 0.999). The comparison of CCT measurements revealed statistically significant differences between Pentacam HR versus IOLMaster 700 (p<0.0001) and Pentacam HR versus Cirrus HD-OCT (p<0.0001), respectively. There was no difference in CCT measurements between IOLMaster 700 and Cirrus HD-OCT (p=0.519). The repeatability of keratometry readings (J0 and J45) of IOLMaster 700, Pentacam HR, and iDesign was also high with ICCs ranging from 0.974 to 0.999. The Pentacam HR revealed significantly higher J0 in comparison to IOLMaster 700 (p=0.009) and iDesign (p=0.041); however, no significant difference was between IOLMaster 700 and iDesign (p=0.426). Comparison of J45 showed no significant difference between IOLMaster 700, Pentacam HR, and iDesign. These results were in accordance with Bland-Altman plots.Conclusion.In clinical practice, the devices analyzed should not be used interchangeably due to low agreement regarding CCT as well as keratometry readings.

scholarly journals Analysis of Lens Thickness Distribution Based on Swept-Source Optical Coherence Tomography (SS-OCT)

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Xi Feng ◽  
Yong Wang ◽  
Jianheng Liang ◽  
Yali Xu ◽  
Julio Ortega-Usobiaga ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Negative Correlation ◽  
Axial Length ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Biometric Data ◽  
Swept Source ◽  
Age Related ◽  
Cataract Patients

Objective. This study aimed to analyze the distribution of lens thickness (LT) and its associations in age-related cataract patients based on swept-source optical coherence tomography (SS-OCT). Methods. This cross-sectional study included 59,726 Chinese age-related cataract patients. Only right-eye data were included in the study. Repeated measures of ocular parameters were performed using an IOL Master 700 device. The distributions of ocular biometric data including anterior chamber depth (ACD), LT, axial length (AL), central corneal thickness (CCT), white-to-white (WTW), and mean keratometry (MK) and their associations with age were assessed. The anterior segment (AS) was measured as the sum of CCT, ACD, and LT, while the vitreous chamber depth (VCD) was calculated as the difference between AL and AS. The values of LT : AL, AS : AL, and VCD : AL in different AL groups and their changes are the main outcome measures used to observe the proportion of the anterior and posterior segments of the eye. Results. Biometric data were available for 59,726 individuals. The mean age was 68.81 years (range = 40–100); 40.62% were male and 59.38% were female. Mean anterior chamber depth (ACD) was 3.02 ± 0.44 mm, mean LT was 4.51 ± 0.44 mm, mean axial length (AL) was 23.89 ± 1.92 mm, mean central corneal thickness (CCT) was 0.53 ± 0.03 mm, mean white-to-white (WTW) was 11.64 ± 0.44 mm, and mean keratometry (MK) was 44.27 ± 1.65 diopter. Female patients had shorter AL, shallower ACD, smaller CCT and WTW, decreased LT, and steeper corneas ( p  < 0.005). ACD revealed the strongest negative correlation ( p  ≤ 0.001, r = –0.682) with LT. Age ( p  ≤ 0.001, r = 0.348) showed a moderate positive correlation, whereas MK ( p  ＜ 0.05, r = 0.011), CCT ( p  ≤ 0.001, r = 0.041) had a weak positive correlation and WTW ( p  ≤ 0.001, r = –0.034) had a weak negative correlation with LT. A nonlinear correlation was found between LT and AL. LT increased with age in both males and females. LT changed variably in eyes with AL less than 27 mm, LT decreased as AL increased, then LT gradually increased as AL increased in extremely long and extra-long eyes ( p  ≤ 0.001). LT : AL and AS : AL decreased as AL increased, VCD : AL gradually increased as AL increased in highly myopic eyes, and VCD : AL increased by about 0.01 for every 1 mm increase in AL. Conclusions. Among Chinese age-related cataract patients, we found LT to have the strongest relation with ACD. The lens was thicker in elderly patients and women. The correlation between LT and AL is not a simple negative correlation; with the increase of age, LT decreases first and then increases. The proportion of VCD is constantly rising with the elongation of AL.

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