Choroidal thickness measurements in young Saudi adult population: a cross-sectional study.

AIM: To determine the choroidal thickness (CT) in young healthy Saudi adults using spectral-domain optical coherence tomography (SD-OCT) with an automated CT segmentation software. METHODS: Fifty-eight young adults (total of 116 eyes), 39 males and 19 females participated in this study between the ages of 18 and 38y (mean 22.65±3.9y). All participants underwent ophthalmic screening examination, including the SD-OCT for measurements of CT in each quadrant egmented into five eccentric regions starting from the foveal region up to 4.5 mm towards the periphery. RESULTS: The choroid was thickest in the foveal region (central 1 mm, 300±60 µm) and began to progressively thinner beyond the parafovea (1.5-2.5 mm, 284±67 µm) towards the peripheral region (3.5-4.5 mm from the fovea, 254±83 µm). The superior choroid showed the thickest profile (309±57 µm), while the nasal choroid exhibited the thinnest (229±76 µm). The rate of the thinning with increasing eccentricity was more predominant in the nasal choroid, which thinned from the foveal region (294±58 µm) to the peripheral region (158±55 µm). The superior and inferior choroid did not show a statistically significant thinning with eccentricity (all P>0.05). There was no statistically significant difference in the CT between gender, age, and laterality of the eyes (all P>0.05). A significant association of myopia with thinner subfoveal choroid was observed (Pearson's, r=0.37), and regression analysis showed that a 10.3 µm choroidal thinning for each diopter increase of myopia. CONCLUSION: CT profile depends on eccentric and the quadrant. The CT profile across the measured area in the young Saudi adult population is comparable to other previous reports. Refractive error is critical for CT evaluation.

Perspectives and clinical practices of optometrists in Saudi Arabia concerning myopia in children.

AIM: To investigate the practice patterns of optometrists in Saudi Arabia regarding myopia management. METHODS: An internet-based survey was distributed to all practicing optometrists in Saudi Arabia (n=1886). The survey contained questions related to 1) demographics, 2) knowledge about myopia and its associated complications, 3) current clinical care, 4) type and frequency of myopia treatment prescribed, and 5) potential barriers limiting treatment adoption. RESULTS: The completed surveys were collected from 171 optometrists (9.06% response rate, 60% male). Knowledge regarding myopia-associated complications was prevalent but somewhat inaccurate among the respondents. Cycloplegic refraction at initial visit was used by 59% of the respondents. The cover test was the most reported binocular vision test (83%), and 38% of optometrists did not perform any ocular biometrics. Two-thirds prescribed single-vision spectacles for children with myopia. Increased time spent outdoors was selected by 80% of the practitioners who prescribed myopia control treatment as the primary approach. Insufficient support and lack of clinical experience in providing myopia treatment were reported as the most important factors limiting the adoption of myopia management strategies. CONCLUSION: The current optometric practices in Saudi Arabia require further investigation. Optometrists appear to be somewhat aware of myopia and the associated risks. However, most evidence-based myopia treatments are not being locally adopted, primarily because of lack of support, lack of experience, and limited availability.

Within-day changes in luminal, stromal choroidal thickness, and choroidal vascularity index in healthy adults.

Purpose: To investigate topographical and within-day changes in the choroidal vascularity index and its association with choroidal thickness parameters (total, luminal, and stromal thickness) among young adults. Methods: : Choroidal thickness and vascularity index were measured in 28 healthy young adults (age mean ± standard deviation [SD]: 25 ± 3.0) using spectral-domain optical coherence tomography. Participants were divided into three refractive groups: emmetropes, myopes, and high myopes. Choroidal parameters were evaluated in the macular and peripheral regions in the superior and inferior regions at two time points during the day; in the morning (at 7 am) and in the afternoon (at 1 pm). Results: : All investigated choroidal thickness parameters showed a significant topographical variation across the vertical meridian, between the foveal (270 ± 89 µm, 170 ± 45 µm, and 111 ± 47 µm, respectively) and peripheral (246 ± 68 µm, 160 ± 39 µm, 86 ± 36 µm, respectively). The superior choroid was thicker in all thickness parameters compared to the inferior choroid. A significant increase in the vascularity percentage was seen from the fovea (61.8 ± 7%) toward the periphery (66.4 ± 7%). Thinner choroidal parameters were associated with high myopia, whereas an increase in the vascularity index was observed in high myopes. Significant within-day changes were observed in all choroidal thickness parameters, which were slightly reduced in the afternoon. The choroidal vascularity index (CVI) increased from 61.3 ± 5.3% in the morning and 63.2 ± 5.8% in the afternoon. High myopes exhibited reduced within-day amplitude in stromal thickness. Conclusion: : All parameters showed significant regional variations. Myopia is associated with greater thinning in stromal thickness rather than vascular thickness. Only high myopes experienced reduced within-day change amplitudes in stromal choroidal thickness that was more predominant in the foveal and parafoveal regions.