Corneal epithelial mapping in different corneal conditions

Abstract Background Cataract surgery is traumatic to the corneal epithelium,scarring and opacity is the commonest cause of blindness. Objective To study the corneal epithelial thickness in different corneal conditions using anterior segment optical coherence tomography (AS-OCT). Patients and Methods A case-control study including 80 eyes divided equally into 4 groups; group 1:controls,group 2:corneal scarring ,group 3:cataract patients and group 4:pterygium. using AS-OCT epithelial mapping to document changes in epithelial thickness in controls, cataract patients pre and 1 month after phacoemulsification, patients with corneal scarring and patients with pterygium. Results In phacoemulsification group; we found that epithelial thickness became thinner in area (0_2) and thicker in area (7_9) mm in the map with no significant change in areas (2_5),(5_7) mm in the map. In corneal scarring group; we found that epithelial thickness became thicker compared to control group in all zones. In pterygium group; we found that epithelial thickness became thicker compared to control group in, areas (2_5), (5_7) & (7_9) mm in the map with no significant change in area (0_2) mm in the map. Conclusion The corneal epithelium thickness becomes thinner or thicker to compensate for changes in stromal thickness.

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Assessment of Corneal Epithelial Thickness in Chronic Contact Lens Users Using Anterior Segment Optical Coherence Tomography

QJM ◽

10.1093/qjmed/hcaa058.006 ◽

2020 ◽

Vol 113 (Supplement_1) ◽

Author(s):

A A M E A Rezk ◽

A Assaf ◽

M Gamil ◽

T Badran

Keyword(s):

Contact Lens ◽

Corneal Epithelium ◽

Refractive Surgery ◽

Anterior Segment ◽

Control Group ◽

Soft Contact ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Soft Contact Lens ◽

Corneal Epithelial Thickness

Abstract Introduction The corneal epithelium is stratified epithelium that is continuously renewed and provides the frontline of defence against invading ocular pathogens and a smooth refractive surface essential for vision. In the absence of a contact lens, pre-existing ocular trauma or disease, the epithelium maintains an inaccessible defence against attacks from pathogenic microorganisms, affording a high level of resistance against microbial invasion. Aim The aim of this study is to determine the effect of chronic use of contact lens on corneal epithelium thickness using anterior segment optical coherence topography as a non- invasive diagnostic accurate measure. Patients and Methods 30 eyes of control subjects who don’t wear contact lens along their life aged between 15-45 years ,where compared with similar age group of 30 eyes of chronic contact lens users; who wear contact lens every day not less than 8 hours per day for along time interval between 6 months up to 5 years. Results The average corneal epithelial thickness in the central, paracentral and midperipheral zones was 47.767 ± 5.550 µm, 46.267 ± 5.644 µm, 44.300 ± 4.858 µm, respectively, in chronic soft contact lens users; and 49.800 ± 3.316 µm, 49.200 ± 3.367 µm, 45.733 ± 2.333 µm ,in control group who had never worn contact lens. There were insignificant thinning of corneal epithelium of soft contact group compared to control group regarding the average corneal epithelial thickness in those 3 zones. In all the 8 sectors of corneal epithelium of paracentral zone and midperipheral zones there is insignificant thinning between the two groups except for the inferior temporal sector in the paracentral zone and mid peripheral zone, which shows significant thinning in soft contact lens group compared to control group. The corneal epithelial thickness in the inferior temporal sector of paracentral and mid peripheral zones was 46.333 ± 5.677 µm, 44.933 ± 4.813 µm, respectively, in chronic soft contact lens users compared to 48.767 ± 3.266 µm, 46.900 ± 2.510 µm in control group (p = 0.046, p = 0.052, respectively). Conclusion AS-OCT helps us to evaluate the corneal epithelium of contact lens users, which could be very useful in corneal refractive surgeries in patients depending on contact lens in their lives as a comfortable refractive aid, It is necessary to do AS-OCT hand on hand with pentacam in patients underwhelming refractive surgery to give a proper assessment to their corneal epithelium before determining which type of refractive surgery suits them.

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The effect of PRK on corneal epithelium thickness and pachmetry in treatment of myopia.

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9ispl1.1285 ◽

2018 ◽

Vol 9 (SPL1) ◽

Author(s):

Furkaan Majied Hamied ◽

Deyaa Neama Kadhim ◽

Sohaib A Mahmood

Keyword(s):

Refractive Error ◽

Anterior Segment ◽

Thickness Change ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Refractive Outcomes ◽

Epithelium Thickness ◽

Profile Changes ◽

Corneal Epithelial Thickness ◽

Myopic Astigmatism

In order to facilitate the corneal stromal ablation in photorefractive keratectomy the epithelium is removed so corneal repair associated with changes in epithelium and stroma. To study the corneal epithelial thickness and pachymetry profile changes after photorefractive keratectomy (PRK) for myopia. Retrospective analysis of the postoperative corneal epithelial thickness and pachymetry profile changes in 22 eyes of 12 patients treated with PRK for myopia or myopic astigmatism. Corneal and epithelial thickness maps within the central 6 mm were obtained by anterior segment spectral-domain optical coherence tomography (SD-OCT) preoperatively and at 3 months postoperatively. Correlations between pachymetry,epithelial thickness changes and the amount of correction,were analyzed.Compared to preoperative values,the central 2 mm and the paracentral 2 to 5 mm zone epithelium was 1 ± 2.85 and 1 ± 3.11 μm thicker,respectively,at 3 months postoperatively (P <.05). The spherical equivalent (SE) changed from-2.80 ± 2.028 diopters (D) preoperatively to -0.40 ± 0.42 D at 3 months postoperatively. Females show greater postoperative epithelial thickening, 2.6 ± 3.77 μm,than males,0.34 ± 1.98 μm. There was a trend toward greater epithelial thickening with a larger amount of programmed SE correction, and thinner preoperative epithelium. No correlation between epithelial thickness change and postoperative change in refraction was detected.Negative correlation between between age, refractive error,with the pre and post-operative pachymetry. In general female pachymetry reading is higher than it in male.The corneal epithelial thickness increased after PRK up to 3 months postoperatively. It was affected by the amount of myopia treated, gender, and preoperative epithelial thickness. The refractive outcomes did not affected by the postoperative epithelial thickening. Negative correlation between between age, refractive error, with the pre and post-operative pachymetry. In general female pachymetry reading is higher than it in male.

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Characterisation of the prereceptor regulation of glucocorticoids in the anterior segment of the rabbit eye

Journal of Endocrinology ◽

10.1677/joe.1.06840 ◽

2006 ◽

Vol 190 (2) ◽

pp. 483-493 ◽

Cited By ~ 9

Author(s):

Claire U Onyimba ◽

Neelima Vijapurapu ◽

S John Curnow ◽

Pamela Khosla ◽

Paul M Stewart ◽

...

Keyword(s):

Epithelial Cells ◽

Corneal Epithelium ◽

Ciliary Body ◽

Primary Cultures ◽

Anterior Segment ◽

Body Tissue ◽

Corneal Epithelial Cell ◽

Corneal Epithelial Cells ◽

Corneal Epithelial ◽

Rabbit Eye

The prereceptor regulation of glucocorticoids (GCs) by 11β-hydroxysteroid dehydrogenase type-1 (11β-HSD1), a bidirectional isozyme that interconverts active (cortisol) and inactive (cortisone) GCs, is an established determinant of GC function in tissues such as liver, adipose and bone. Although the therapeutic use of GCs is abundant in ophthalmic practice, where GC interactions with nuclear receptors modulate gene transcription, the prereceptor regulation of endogenous cortisol is not well described in ocular tissues. Recent descriptive studies have localised 11β-HSD1 to the human corneal epithelium and non-pigmented epithelium (NPE) of the ciliary body, indicating a link to corneal epithelial physiology and aqueous humour production. In this study, we characterise the functional aspects of the autocrine regulation of GCs in the anterior segment of the rabbit eye. Using our in-house generated primary antibody to human 11β-HSD1, immunohistochemical analyses were performed on paraffin-embedded sections of whole New Zealand white albino rabbits, (NZWAR) eyes. As in human studies, 11β-HSD1 was localised to the corneal epithelium and the NPE. No staining was seen in the albino ‘pigmented’ ciliary epithelium. Specific enzyme assays for oxo-reductase (cortisone→cortisol) and dehydrogenase (cortisol→cortisone) activity indicated predominant 11β-HSD1 oxo-reductase activity from both the intact ciliary body tissue (n=12, median 2.1 pmol/mg per h and range 1.25–2.8 pmol/mg per h; P=0.006) and primary cultures of corneal epithelial cells (n=12, median 3.0 pmol/mg per h and range 1.0–7.4 pmol/mg per h, P=0.008) compared with dehydrogenase activity (median 1.0 pmol/mg per h and range 0.5–2.0 pmol/mg per h; median 0.5 pmol/mg per h and range 0.25–1.9 pmol/mg per h respectively). These findings were supported by expression of 11β-HSD1 protein as visualised by Western blotting of ciliary body tissue and immunocytochemistry of corneal epithelial cells. Reduction of corneal epithelial cell proliferation was seen after primary cultures were co-incubated with cortisol and cortisone. 11β-HSD1 activity was not demonstrated in naïve conjunctival fibroblasts or corneal stromal keratocytes. Our results indicate that the distribution of 11β-HSD1 in the rabbit resembles that of the human eye and activates cortisone to cortisol in both corneal and uveal tissues. The NZWAR provides a suitable in vivo model for the further evaluation of 11β-HSD1 activity in the eye, especially its role in corneal epithelial and ciliary body physiology.

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Redistribution of the Corneal Epithelium After Overnight Wear of Orthokeratology Contact Lenses for Myopia Reduction

10.21203/rs.2.104/v1 ◽

2018 ◽

Author(s):

Ju Zhang ◽

Jing Li ◽

Xiaofeng Li ◽

Fengjie Li ◽

Ting Wang

Keyword(s):

Visual Acuity ◽

Corneal Epithelium ◽

Contact Lenses ◽

Early Stage ◽

Corneal Thickness ◽

Topographic Map ◽

Epithelial Thickness ◽

Uncorrected Visual Acuity ◽

Before And After ◽

Epithelium Thickness

Abstract Background: To investigate changes in the corneal epithelium topographic map in juvenile myopia after overnight wear of orthokeratology lenses (OK). Methods: A total of 53 juveniles (53 right eyes) successfully wore OK and were reviewed in a timely manner from January 2016 to July 2017. Epithelial and corneal data were obtained by optical coherence tomography (OCT). Changes in uncorrected visual acuity, diopter, corneal refractive power, and epithelial and corneal thickness were analyzed before and after 1 day, 1 week, and 1 mo of overnight wear of OK. Results: The corneal epithelium was reshaped after 1 day of OK; the myopia degree was reduced, and uncorrected visual acuity reached 0 logMAR at 1 week. The central (2-mm) average epithelial thickness was 52.04±2.35 μm, 49.25±2.67 μm, 45.91±2.80 μm, and 47.53±3.44 μm before and after 1 day, 1 week, and 1 mo of OK, respectively (t=10.122, 10.782, and 10.673, respectively, P≤0.001). The central epithelium appeared to have a thinning trend, which was obvious at 1 week, when the average thinning of 6.13±1.67 μm accounted for approximately 11.78%±3.21% of the total epithelium thickness. The epithelial thickness of the reverse curve zone was 51.83±2.49 μm, 57.62±3.01 μm, 59.43±3.19 μm, and 60.22±2.75 μm before and after 1 day, 1 week, and 1 mo of OK, respectively, showing a significant increase over time (t=5.325, 6.177, and 6.312, respectively, P≤0.001). Conclusion: In the early stage of OK, the corneal epithelium was redistributed very quickly. The central epithelium became thin, while the epithelium of the reverse curve zone correspondingly thickened and achieved a plateau at 1 mo. Epithelial redistribution guaranteed uncorrected visual acuity after removal of OK.

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Thickness profiles of the corneal epithelium along the steep and flat meridians of astigmatic corneas after orthokeratology

10.21203/rs.2.15658/v2 ◽

2020 ◽

Author(s):

Jiaqi Zhou ◽

Feng Xue ◽

Xingtao Zhou ◽

Rajeev Krishnan Naidu ◽

Yishan Qian

Keyword(s):

Optical Coherence Tomography ◽

Visual Acuity ◽

Prospective Study ◽

Corneal Epithelium ◽

Fourier Domain ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Corneal Epithelial Thickness ◽

A Prospective Study ◽

Lens Wear

Abstract Background: To investigate the changes in corneal epithelial thickness along the principle meridians of astigmatic corneas after six months of overnight spherical myopic orthokeratology (OK) lens wear. Methods: A prospective study. Fifty-seven subjects with up to 1.50 diopters (D) of corneal toricity wore spherical OK lenses for 6 months. Evaluations of OK lens fit, visual acuity, refractions and corneal toricity (CT) were performed. Fourier-domain optical coherence tomography (FD-OCT) was conducted to measure the corneal epithelial thickness (ET) along the principle meridians of corneal toricity over a diameter of 6mm. The means of △ET of the same diameter at individual meridians (△ETSm and △ETFm) were calculated and compared. Results: Visual acuity and refraction improved significantly after OK lens wear. △ETFm (-4.2±3.4μm) thinned more than △ETSm (-3.4±4.0μm, P=0.027) at 1.5mm in radius. △ETSm thickened more than △ETFm at 2.5mm (△ETSm: 4.1±5.1μm, △ETFm: 2.8±4.2μm, P=0.019) and 3.0mm (△ETSm: 5.0±5.0μm, △ETFm: 3.7±4.9μm, P=0.036).∣△ETSm - △ETFm∣ were significantly correlated with the baseline central CT at 2.0mm, 2.5mm and 3.0mm (2.0mm: r=0.285, P=0.032; 2.5mm: r=0.422, P=0.001; 3.0mm: r=0.239, P=0.027). ∣△ETSm - △ETFm∣was significantly correlated with the baseline peripheral CT at 2.5mm (r=0.299, P=0.028). Conclusions: Overnight wear of spherical OK lenses resulted in differential changes in the thickness profiles of the corneal epithelium between the steep and flat meridians in eyes with corneal toricity.

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New model to better diagnose dry eye disease integrating OCT corneal epithelial mapping

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2021-318826 ◽

2021 ◽

pp. bjophthalmol-2021-318826

Author(s):

Norah A Edorh ◽

Adil El Maftouhi ◽

Zoubir Djerada ◽

Carl Arndt ◽

Alexandre Denoyer

Keyword(s):

Dry Eye ◽

Roc Curves ◽

Dry Eye Disease ◽

Eye Disease ◽

Control Group ◽

Scoring Method ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Final Multivariable Model ◽

The Difference

PurposeTo optimise the objective diagnosis of dry eye disease (DED), the capabilities of wide corneal epithelial mapping using optical coherence tomography (OCT) were studied and subsequently integrated into a new scoring method.MethodsFifty-nine patients (118 eyes) with DED and 55 control subjects (110 eyes) were included. All patients underwent a complete ocular surface evaluation. Corneal epithelial thickness was collected using OCT for seven zones. DED and the control group were compared using a t-test, and univariate receiver operating characteristic (ROC) curves were calculated to define the diagnostic ability of OCT epithelial mapping. Multivariate analyses were performed using artificial intelligence (random forest) and logistic regression approaches to define the best way to integrate OCT mapping in the diagnosis of DED. Then, a final multivariable model for diagnosing DED was validated through a bootstrapping method.ResultsThe DED group had significant epithelial thinning compared with the controls, regardless of location. Superior intermediate epithelial thickness was the best marker for diagnosing DED using OCT (binormal estimated area under ROC: 0.87; best cut-off value: 50 µm thickness). The difference between the inferior and superior peripheral zones was the best marker for grading the severity of DED (analysis of variance, p=0.009). A multivariate approach identified other significant covariables which were integrated into a multivariate model to improve the sensitivity (86.4%) and specificity (91.7%) of this innovative diagnostic method.ConclusionIncluding OCT corneal epithelial mapping in a new diagnostic tool for DED could allow optimisation of the screening and staging of the disease in current practice as well as for clinical research purposes.

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Effect of Age on Individual Corneal Epithelial Thickness in Normal Eyes as Measured with Ultrasound Pachymeter

Journal of Ophthalmology & Clinical Research ◽

10.33140/jocr.05.01.03 ◽

2021 ◽

Vol 5 (1) ◽

Keyword(s):

Corneal Epithelium ◽

Corneal Thickness ◽

Age Groups ◽

Age Group ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Significant Difference ◽

The Mean ◽

Corneal Epithelial Thickness ◽

Ultrasound Pachymeter

Purpose: The goal of this study was to determine age-relatedvariation in the thickness of the corneal epithelium using ultrasound pachymeter. Methods: One hundred three patients were enrolled in this study and grouped according to age: Group A (< 30 years), group B (31-40 years), group C (41-50 years), group D (51-60 years), group E (61-70), and group F (> 71). Total corneal and corneal epithelial thickness measurements were made using the SonogageCorneo-Gage Plus 2 (Cleveland, Ohio) ultrasound pachymeter. Correlations of central epithelial thickness with central total corneal thickness, age, and gender were calculated. In addition, mean central epithelial thickness (CET) was measured. One-way ANOVA testing and post hoc analysis with the Tukey test and Pearson correlation were performed to analyze data. Results: The mean epithelial thickness at the central cornea was 47.88±1.15 μm, with no statistically significant difference between right and left eyes, and no significant differences in gender or central total corneal thickness. The difference in mean epithelial thickness across age groups was statistically significant (p <0.008). The mean epithelial thickness of the > 71 years group was significantly thinner than that of the < 30 years, 31-40, 41-50, and 51-60 years age groups. Conclusions: Ultrasound pachymeter of the corneal epithelium demonstrated that the oldest age group (> 71 years) had significantly thinner central corneal epithelial thickness than the younger age groups. There was no correlation between epithelial thickness, total corneal thickness, gender, or laterality.

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Role of α1-adrenoceptor subtypes on corneal epithelial thickness and cell proliferation in mice

AJP Cell Physiology ◽

10.1152/ajpcell.00314.2018 ◽

2018 ◽

Vol 315 (5) ◽

pp. C757-C765 ◽

Cited By ~ 2

Author(s):

Aytan Musayeva ◽

Caroline Manicam ◽

Andreas Steege ◽

Christoph Brochhausen ◽

Beate K. Straub ◽

...

Keyword(s):

Cell Proliferation ◽

Epithelial Cell ◽

Cell Size ◽

Corneal Epithelium ◽

Messenger Rna ◽

Rank Order ◽

Wild Type ◽

Corneal Epithelial ◽

Epithelial Thickness ◽

Corneal Epithelial Thickness

Adrenergic stimuli are important for corneal epithelial structure and healing. The purpose of the present study was to examine the hypothesis that the lack of a single α1-adrenoceptor (α1-AR) subtype affects corneal epithelial thickness and cell proliferation. Expression levels of α1-AR mRNA were determined in mouse cornea using real-time PCR. In mice devoid of one of the three α1-AR subtypes (α1A-AR−/−, α1B-AR−/−, α1D-AR−/−) and in wild-type controls, thickness of individual corneal layers, the number of epithelial cell layers, and average epithelial cell size were determined in cryosections. Endothelial cell density and morphology were calculated in corneal explants, and epithelial cell proliferation rate was determined with immunofluorescence microscopy. Moreover, the ultrastructure of the corneal epithelium was examined by transmission electron microscopy. Messenger RNA for all three α1-AR subtypes was expressed in whole cornea and in corneal epithelium from wild-type mice with a rank order of abundance of α1A ≥ α1B > α1D. In contrast, no α1-AR mRNA was detected in the stroma, and only α1B-AR mRNA was found in the Descemet endothelial complex. Remarkably, corneal epithelial thickness and mean epithelial cell size were reduced in α1A-AR−/− mice. Our findings suggest that the α1A-AR exerts growth effects in mouse corneal epithelial cells.

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