Purpose. To identify and correlate age-related changes in outer retinal layers’ thickness and choroidal thickness (CT) in the normal eyes using spectral-domain optical coherence tomography (SD-OCT) and to investigate factors affecting these changes. Study Design. Observational cross-sectional study. Subjects and Methods. We studied 125 healthy Egyptians between 20 and 79 years old. Patients were divided into 3 groups: group 1 (20–40 years), group 2 (40–60 years), and group 3 (>60 years). All patients had full ophthalmic examination. SD-OCT was done to measure the 9 ETDRS macular grid sectors of retinal pigment epithelium and photoreceptor outer segment (RPE-OS), outer nuclear layer and photoreceptor inner segment (ONL-IS), and choroidal thickness (CT) (by enhanced depth imaging). Results. RPE-OS was significantly thinner in group 3 than in the other 2 groups (central: P<0.001). Moreover, the 3 groups were significantly different from each other regarding the CT (central: P<0.001); significant thinning was noticed in the choroid with age. The 3 groups did not show significant difference concerning the ONL-IS thickness. RPE-OS and CT showed statistically significant negative correlation with age (central RPE-OS: r = −0 C.345, P<0.001, and central CT: r = −0.725, P<0.001) while ONL-IS showed statistically nonsignificant correlation with age (central ONL-IS: r = −0.08, P=0.376). Multiple regression analysis revealed that the most important determinant of central 1 mm RPE-OS thickness in this study was age (β = −0.087, P=0.010) rather than choroidal thinning (β = 0.001, P=0.879). Conclusion. RPE-OS layer thickness shows significant thinning with increasing age, and with decrease in CT, however, age is the most determinant factor of this thinning.

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Background: Diabetic Retinopathy (DR) is a major cause of vision loss in the working age population and people with diabetes are 25 times more likely than the general population to go blind. Aim of Study: To correlate the Best-Corrected Visual Acuity (BCVA) by ETDRS protocol with macular thickness measurement and morphology as obtained by OCT in a series of patients with diabetic macular edema, with or without diabetic retinopathy. Patients and Methods: Cross sectional design, in total 102 of 51 selected Egyptian diabetic subjects, 20 males and 31 females were selected by convenient sample in the study during the period from Mars. 2018 to December 2018, all procedures were done at National Institute Of Diabetes And Endocrinology. Eyes enrolled in the study were divided into three groups as follows: Group 1: Eyes with DME and non clinically detectable DR, Group 2: Eyes with DME and NPDR, Group 3: Eyes with DME and PDR. Results: In the present study,we found that the Diffuse Spongy Macular Edema (DSME) was the most common type of DME, we found a highly significant negative correlation between the CMT and BCVA. There was a significant correlation between the OCT pattern of DME and the severity of diabetic retinopathy. We also found a statistically significant decrease in BCVA in eyes with PDR in comparison to eyes with NPDR and eyes with no clinically detectable diabetic retinopathy. Conclusion: Based on the data in our study, diffuse spongy macular edema was the most common type of DME with the least CMT and the highest BCVA, we also found the worst BCVA in PDR.

Background Measurement of intraocular pressure (IOP) plays a central role throughout ophthalmology. It is part of routine ophthalmologic examinations and important in the management and follow-up of patients with glaucoma. While elevated IOP remains the most important risk factor for development and progression of open angle glaucoma, at least half of the population diagnosed with open angle glaucoma is asymptomatic. Objectives The aim of our study is to compare the accuracy of intraocular pressure measurement before and after Laser in situ keratomeulsis (LASIK) surgery using three different types of Tonometers: Goldmann Applanation tonometry (GAT), Non contact tonometry (NCT) and Rebound tonometry (I care), considering the change in the central corneal thickness (CCT). Patients and Methods In this study Eighty eyes of 40 patients with mean age of 27.00±6.00 years were scheduled for LASIK..Central corneal thickness before and after surgery was obtained by Ultrasound (US) pachymetry.IOP values were measured before and after surgery using three different types of Tonometers: Goldmann Applanation tonometry, Non contact tonometry and Rebound tonometry. Results The results revealed that lower post-operative IOP measurements using all techniques. The least affected technique was Non –contact with IOP change 16%, followed by GAT with IOP change 18%, and finally Rebound with IOP change 19 %, respectively. The percentage of change in CCT between pre- and post- LASIK surgery measured with the Ultrasound pachymetry was statistically highly significant. There was a clinical significant correlation between Percentage of tissue ablation (PTA) and IOP change for GAT, NCT and rebound tonometry. Also, there was a significant correlation between Residual stromal bed (RSB) and IOP change for GAT and NCT. There was no clinical significant correlation between Ablation depth (AD) and percentage of change of IOP measurements pre and post LASIK, except for IOP measured with GAT when AD &lt; 40.00 µm. Conclusion Refractive surgery causes significant lowering of IOP as measured using Goldmann applanation tonometry, non contact tonometry and rebound tonometry. The least affected tonometry post LASIK is non contact tonometry. The reduction was correlated to the percentage of tissue ablated. The ideal method to measure IOP in post-LASIK patients would be a device that is free of corneal factors.