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

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A A M E A Rezk ◽  
A Assaf ◽  
M Gamil ◽  
T Badran

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.

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Fatma El-Hennawi ◽  
Hazem Rashed ◽  
Reham Fawzy ◽  
Kholoud Selim

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.


Author(s):  
Furkaan Majied Hamied ◽  
Deyaa Neama Kadhim ◽  
Sohaib A Mahmood

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.


2014 ◽  
Vol 91 (12) ◽  
pp. 1455-1461 ◽  
Author(s):  
Jiaxu Hong ◽  
Tingting Qian ◽  
Yujing Yang ◽  
Chunhui Jiang ◽  
Zuguo Liu ◽  
...  

2020 ◽  
Author(s):  
Jiaqi Zhou ◽  
Feng Xue ◽  
Xingtao Zhou ◽  
Rajeev Krishnan Naidu ◽  
Yishan Qian

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.


2021 ◽  
Vol 5 (1) ◽  

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.


Sign in / Sign up

Export Citation Format

Share Document