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Evaluating factors affecting corneal higher-order aberration component has a very important role in interpreting the characteristics of the formed image on the retina. To determine the relationship between ocular biometric components and corneal higher-order aberrations in an elderly population. This report is related to a subsample of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on individuals aged 60 years and above in Tehran city, Iran using multistage stratified random cluster sampling. All study participants underwent ocular examinations including visual acuity measurement, refraction and slit-lamp biomicroscopy. Anterior segment imaging and corneal aberrometry were performed using Pentacam AXL. In the present study, 644 eyes of 415 individuals (56.9% female) with mean age of 66.36 ± 4.70 years were evaluated. According to a multiple generalised estimating equation model, the root mean square of total higher-order aberrations was related to age (β = 0.081, p = 0.002), crystalline lens thickness (β = 0.08, p < 0.001), and corneal diameter (β = -0.04, p = 0.014). The root mean square of total coma aberration was directly related to the female sex (β = 0.02, p = 0.05), and crystalline lens thickness (β = 0.06, p < 0.001). There was a direct relationship between the root mean square of third- and fourth-order higher-order aberrations and crystalline lens thickness (p < 0.001). Spherical aberration was directly related to the male sex (β = -0.02, p = 0.004), axial length (β = 0.05, p < 0.001) and central corneal thickness (β = 0.001, p = 0.025), and was inversely related to anterior chamber depth (β = -0.07, p = 0.031) and crystalline lens thickness (β = -0.25, p < 0.001). Ocular biometric components are related to corneal aberrations in the elderly. These factors need to be considered in respect of medical and surgical procedures required for the elderly. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to determine the 5‐year changes in macular thickness and related factors. Methods: Data were from the second (2014) and third (2019) phases of the Shahroud Eye Cohort Study. Examinations included measurement of uncorrected and best‐corrected visual acuity, non‐cycloplegic autorefraction, slit‐lamp biomicroscopy, and funduscopy. Participants underwent Cirrus HD‐OCT 4000 (Carl Zeiss Meditec, Dublin, CA). imaging. Results: The 5‐year changes (95% confidence interval) of central and overall macular thicknesses were − 3.48 ± 8.16 μ (−3.92, −3.03) and − 0.79 ± 4.06 μ (−1.03, −0.54), respectively. The median and IQR of 5‐year changes in the central subfield thickness were −3 and 10, although they were 0 and 5 in the overall macular thickness, respectively. Multiple regression model showed the central macular thickness (CMT) decreased with a U‐shape pattern with increasing age. The 5‐year changes in CMT were significantly lower in females compared to males β = −1.55; (−2.78, −0.32) and in smokers compared to non‐smokers β = −1.92; (−3.55, −0.28). Moreover, higher body mass index β = −0.12; (−0.22, −0.02) and CMT at baseline β = −0.08; (−0.10, −0.06) were significantly associated with lower CMT changes. The average 5‐year changes in overall macular thickness showed a non‐linear decrease with age and was significantly higher in females β = 0.93; (0.4, 1.43). These changes were directly related to the anterior chamber depth β = 0.87; (0.10, 1.64) in the baseline. Conclusions: The macular thickness decreased slightly after 5 years; however, this change is not clinically significant. Demographic factors such as age and sex and refractive errors were significantly related to macular thickness changes. [ABSTRACT FROM AUTHOR]

Knowing normative corneal optical density (COD) values is important for identifying pathologic corneal changes. The aim of this work is to determine the distribution and associated factors of COD in the elderly population. This report is a part of a cross-sectional population-based study conducted on the elderly population (≥60 years) of Tehran, Iran from Jan 2019 to Jan 2020. Using a multi-stage stratified random cluster sampling method, a total of 160 clusters were randomly selected from 22 districts of Tehran city. Study participants underwent a complete ocular examination including measurement of visual acuity, refraction, and slit-lamp biomicroscopy. Corneal densitometry was evaluated using the Pentacam HR. Generalized estimating equation (GEE) models were used to investigate associations of COD with study variables. A total of 3633 eyes from 2068 individuals were analysed. Of these, 1256 (60.7%) were female, and the mean age of the individuals was 66.42 ± 5.28 (60 to 95) years. The mean entire COD was 21.96 ± 4.45 greyscale unit (GSU) (95% CI: 21.57–22.34). There was a statistically significant difference in the mean COD between the anterior, central, and posterior layers (p < 0.001); the highest and lowest average COD was related to the anterior and posterior corneal layers, respectively. The lowest and highest mean COD were observed in the 0–2 mm [17.21GSU (95% CI:16.87–17.55)], and 10–12 mm annular zones [31.4 GSU (95% CI: 30.89–31.91)], respectively (p < 0.001). According to the multiple GEE model, the COD had a statistically significant direct relationship with age, central corneal thickness, and mean keratometry, while it was significantly inversely associated with female sex, anterior chamber depth, white-to-white distance, and corneal volume. These normal values of COD in the present study could be used as reference data in older adults. The associated factors of COD should be taken into account to avoid misinterpretation of physiologic changes as pathologic processes. [ABSTRACT FROM AUTHOR]