Decreased epithelial to corneal thickness ratio in healthy fellow eyes of patients with unilateral bullous keratopathy

2019 ◽  
Vol 104 (2) ◽  
pp. 230-234
Author(s):  
Alexei N Kulikov ◽  
Dmitrii S Maltsev ◽  
Elena V Kudryashova ◽  
Maria A Burnasheva
Keyword(s):  
Corneal Thickness ◽  
Anterior Segment ◽  
Central Area ◽  
Bullous Keratopathy ◽  
Specular Microscopy ◽  
Healthy Individuals ◽  
Epithelial Thickness ◽  
The Relationship ◽  
Subclinical Dysfunction ◽  
Fellow Eyes

PurposeTo study the relationship between epithelial thickness (ET) and corneal thickness (CT) in healthy fellow eyes of patients with unilateral bullous keratopathy (BKP) and healthy subjects.MethodsSeventeen BKP patients (nine males, eight females, 73.2±10.4 years) and 40 healthy individuals (20 males, 20 females, 69.5±9.8 years) were included. All participants received anterior segment optical coherence tomography and specular microscopy with calculation of endothelial cell density. ET, CT, stromal thickness and ET-to-CT ratio were defined automatically (within 2 mm central area). Central epithelial thickness (CET) and central corneal thickness (CCT) were measured manually at the corneal centre and stromal thickness and CET-to-CCT ratio were calculated.ResultsIn healthy fellow eyes of BKP patients compared with eyes of healthy individuals ET was statistically significantly lower (p<0.001) while CT was statistically significantly higher (by 28.9 and 30.9 µm in 2 mm zone and corneal centre, respectively). Both 2 mm ET-to-CT ratio (0.091±0.01 and 0.10±0.004, respectively [p<0.001]) and CET-to-CCT ratio (0.083±0.006 and 0.97±0.005, respectively [p<0.0001]) were statistically significantly lower in healthy fellow eyes of BKP patients compared with eyes of healthy individuals. To identify healthy fellow eyes of BKP patients, area under curve for CET-to-CCT ratio and CET was 0.94 and 0.80, respectively (p=0.01), and for 2 mm ET-to-CT ratio and 2 mm ET was 0.91 and 0.80, respectively (p=0.03).ConclusionDecreased СET-to-СCT ratio resulting from simultaneous epithelial thinning and stromal thickening without significant corneal thickening indicates subclinical dysfunction of corneal endothelium in healthy fellow eyes in unilateral BKP patients.

scholarly journals Relationship among Corneal Biomechanics, Anterior Segment Parameters, and Geometric Corneal Parameters

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Sadık Görkem Çevik ◽  
Sertaç Argun Kıvanç ◽  
Berna Akova-Budak ◽  
Mediha Tok-Çevik
Keyword(s):  
Corneal Thickness ◽  
Anterior Segment ◽  
Biomechanical Properties ◽  
Negative Association ◽  
Corneal Resistance Factor ◽  
Multivariate Models ◽  
Corrected Visual Acuity ◽  
Biomechanical Parameters ◽  
Anterior Segment Parameters ◽  
The Relationship

Purpose. To investigate the relationship between corneal biomechanical parameters, anterior segment parameters, and geometric corneal parameters in a healthy Caucasian group. Methods. This retrospective study included the healthy eyes with best corrected visual acuity of at least 20/40 of 122 Caucasian subjects. The anterior segment parameters and geometric corneal parameters such as corneal volume, central corneal thickness, horizontal and vertical corneal radii, anterior and posterior steep, and flat keratometric values were measured with a Scheimpflug camera. The biomechanical properties were measured with Ocular Response Analyzer. Results. One hundred and twenty-two healthy Caucasian subjects (67 males, 55 females) with a mean age of 45.32±20.23 were enrolled. Both corneal hysteresis and corneal resistance factor were positively correlated with CCT (r=0.529, p<0.001; r=0.638, p<0.001) and CV (r=0.635, p<0.001; r=0.579, p<0.001) and negatively correlated with age (r=-0.373, p<0.001; r=-0.249, p<0.001). Both in age-gender and multivariate models, CH and CRF had statistically significant negative association with the posterior steep K value. Conclusions. CH and CRF are negatively correlated with posterior steep and average posterior K values.

Comparison of Central Corneal Thickness Measurements Using Ultrasonic Pachymetry, Anterior Segment OCT and Noncontact Specular Microscopy

2017 ◽  
Vol 26 (10) ◽  
pp. 860-865 ◽  
Author(s):  
Riccardo Scotto ◽  
Alessandro Bagnis ◽  
Marina Papadia ◽  
Carlo Alberto Cutolo ◽  
Domenico Risso ◽  
...  
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Specular Microscopy ◽  
Anterior Segment Oct ◽  
Thickness Measurements ◽  
Ultrasonic Pachymetry

scholarly journals Repeatability of corneal and epithelial thickness measurements with anterior segment optical coherence tomography in keratoconus

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0248350
Author(s):  
Ye Li ◽  
Akilesh Gokul ◽  
Charles McGhee ◽  
Mohammed Ziaei
Keyword(s):  
Optical Coherence Tomography ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Anterior Segment ◽  
Optical Coherence ◽  
Epithelial Thickness ◽  
History Of ◽  
Group A ◽  
Temporal Aspect ◽  
Group B

Purpose To investigate the repeatability in corneal thickness (CT) and epithelial thickness (ET) measurements using spectral domain anterior segment optical coherence tomography (AS-OCT, REVO NX, Optopol) in keratoconus, and examine the effect of corneal crosslinking (CXL) on repeatability. Methods A cross-sectional study of 259 eyes of 212 patients with keratoconus attending the corneal disease clinic at a university hospital tertiary referral center were enrolled. Two groups were analysed: eyes with no prior history of CXL (Group A) and eyes with prior CXL (Group B). Repeatability of measurements was assessed using the intraclass correlation coefficient (ICC) and coefficient of variation (CV). Results In Group A, central corneal thickness (CCT) was 472.18 ± 45.41μm, and the ET was found to be the thinnest in the inferior-temporal aspect at 51.79 ± 5.97μm and thickest at the superior-nasal aspect at 56.07 ± 5.70μm. In Group B, CCT was 465.11± 42.28μm, and the ET was the thinnest at the inferior-temporal aspect at 50.63 ± 5.52μm and thickest at the superior aspect at 56.80 ± 6.39μm. When evaluating CT measurements, ICC was above 0.86 and 0.83 for Group A and Group B respectively. When evaluating ET measurements, ICC was above 0.82 for both groups. CXL had no statistically significant impact on the repeatability of measurements. Conclusions AS-OCT provides repeatable CT and ET measurements in the central and peripheral cornea in patients with keratoconus. Repeatability is not affected by a history of CXL.

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

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.

scholarly journals A Rabbit Model Study to Determine the Efficacy of a Prototype Corneal Endothelium Protector during Cataract Surgery

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Annabel C. Y. Chew ◽  
Anita Chan ◽  
Monisha E. Nongpiur ◽  
Gary Peh ◽  
Veluchamy A. Barathi ◽  
...  
Keyword(s):  
Corneal Endothelium ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Rabbit Model ◽  
Cell Loss ◽  
Specular Microscopy ◽  
Endothelial Cell Loss ◽  
Surgical Time ◽  
Model Study ◽  
Significant Difference

Purpose. We evaluated the efficacy and safety of a mechanical device, the P-chute, in corneal endothelium preservation during phacoemulsification in a rabbit model. Methods. Twenty-four rabbits were randomly assigned into 2 groups. One eye of each rabbit underwent phacoemulsification that simulated the removal of a dense nucleus, with or without the P-chute. Serial slit-lamp examinations, anterior segment optical coherence tomography (ASOCT) scans, and specular microscopy were performed. Three rabbits from each group were sacrificed on postoperative days (PODs) 1, 5, 7, and 14. Histological analysis of the corneas was performed. Results. There was a trend towards lesser endothelial cell loss for the P-chute group at POD1 (4.9% versus 12.5%, p=0.53), POD5 (10.4% versus 12.2%, p=0.77), and POD7 (10.5% versus 17.2%, p=0.52). There was no significant difference in the corneal thickness (p=>0.05) between the 2 groups. The insertion of the device was challenging. The use of the P-chute only added an extra 15% to the surgical time. Conclusions. There was a trend towards better endothelium preservation with the P-chute even though the results were not statistically significant. We believe that the device could be useful in certain surgical situations. Further work is needed to improve the device insertion.

scholarly journals The corneal effects of intravitreal dexamethasone implantation

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.

Effects of topical antiglaucomatous medications on central corneal epithelial thickness by anterior segment optical coherence tomography

2020 ◽  
Vol 30 (6) ◽  
pp. 1519-1524
Author(s):  
Emine Doğan ◽  
Burçin Köklü Çakır ◽  
Nilgün Özkan Aksoy ◽  
Erkan Celik ◽  
Ünal Erkorkmaz
Keyword(s):  
Optical Coherence Tomography ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Tear Film ◽  
Optical Coherence ◽  
Corneal Epithelial ◽  
Duration Of Therapy ◽  
Epithelial Thickness ◽  
Corneal Epithelial Thickness

Purpose: To evaluate the effect of topical antiglaucomatous medications on central corneal epithelial thickness measured by anterior segment optical coherence tomography. Materials and methods: A total of 153 eyes of 153 patients using topical antiglaucomatous medications and 110 eyes of 110 control subjects were enrolled. Glaucoma type, duration of therapy, the number of drugs, and drops/day were noted in the patient group. Patients and control subjects underwent ocular examinations including Schirmer test, slit lamp examination for tear film break-up time, and anterior segment optical coherence tomography for central corneal thickness and central corneal epithelial thickness. Central corneal epithelial thickness and other data were evaluated separately with regard to glaucoma type, duration of therapy, the number of drops, and drugs in the patient group. Results: The mean ages of the patients and controls were 60.1 ± 10.8 and 58.7 ± 11.2 years, respectively. The groups were similar with regard to mean age and gender (p = 0.058, p = 0.734, respectively). The median (interquartile range) central corneal thickness was 536 (54) µm in patients and 552 (53) µm in controls (p = 0.011). The median (interquartile range) central corneal epithelial thickness of patients and controls were 56 (4) µm and 60 (8) µm, respectively (p < 0.001). The median (interquartile range) tear film break-up time and Schirmer were 12 (6) s and 10 (8) mm in patients and 16 (2) s and 18 (4) mm in controls, respectively (p < 0.001, p < 0.001). In patient group, there was no significant difference in the median central corneal thickness, central corneal epithelial thickness, and tear film break-up time in terms of glaucoma type, duration of therapy, the number of drugs, and the number of daily drops. Only the median Schirmer test was found to be statistically lower in terms of number of daily eye drops (p = 0.039). Conclusion: Using topical antiglaucomatous medications seems to affect the central corneal epithelial thickness in glaucoma patients. Central corneal epithelial thickness was thinner in glaucoma patients than controls. Anterior segment optical coherence tomography might be helpful to evaluate the effect of antiglaucomatous medications on central corneal epithelial thickness during treatment.

scholarly journals Comparison of Four Methods for Corneal Thickness Measurement

2013 ◽  
Vol 6 (1) ◽  
pp. 37-42
Author(s):  
Teodora L. Marinova ◽  
Vesela Ivancheva ◽  
Svilena S. Peeva ◽  
Christina N. Grupcheva
Keyword(s):  
Optical Coherence Tomography ◽  
Laser Scanning ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Segment ◽  
Laser Scanning Confocal Microscopy ◽  
Thickness Measurement ◽  
Specular Microscopy ◽  
Optical Coherence ◽  
Cornea Thickness

Summary The aim of the study was to evaluate the thickness of the normal cornea in order to establish correlation between four methods of measuring including: ultrasound pachymetry (USP), anterior segment optical coherence tomography (ASOCT), non-contact tono/pachymetry (TONOPACHY) and laser-scanning confocal microscopy (LSCM). The study was based on evaluating repeatability and comparability of four different methods formeasuring the corneal thickness. Non contact specular microscopy was first performed on all 27 patients (aged between 20 and 24 years) to evaluate corneal characteristics and confirm the absence of pathological changes. Each participant was examined by USP, ASOCT and TONOPACHY, and 13 eyes of 10 persons were also examined by LSCM. The values of average central corneal thickness measured by USP, ASOCT, TONOPACHY and LSCM were 532.20±4.5 pm, 553.33±12.1 pm, were 548.20±5.62 pm and 573.33±7.22 pm, respectively. There was a high correlation between the instruments. The mean differences for central corneal thickness measurements were 41.43±1.67 pm between USP and LSCM, 20.43±2.4 pm between USP and ASOCT, and 22.1 ±3.88 pm between USB and TONOPACHY. Anterior segment optical coherence tomography overestimated corneal thickness as compared with that measured by USP, which is believed to be a gold standard. Anterior segment optical coherence tomography had better agreement with USP, as compared with LSCM. However, the results of measured cornea thickness by TONOPACHY were very close to cornea thickness measured by ASOCT.

Sign in / Sign up

Export Citation Format

Share Document