Comparison of choroidal thickness in normal eyes and different ocular pathologies in a Brazilian population

• Main Author: Polizelli,Murilo U.
• Publication Date: 2020
• Other Authors: Regatieri,Caio V., Kniggendorf,Vinicius F., Cruz,Natasha F. S. da, Almeida,César G., Novais,Eduardo A., Rodrigues,Eduardo B.
• Format: Article
• Language: eng
• Source: Revista Brasileira de Oftalmologia (Online)
• Download full: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0034-72802020000300169
• topic: Choroid; Diabetic retinopathy; Macular degeneration; Myopia; Tomography, optical coherence

Abstract Objective: To evaluate the choroidal thickness (CT) in healthy Brazilian subjects using spectral-domain optical coherence tomography (SD-OCT) and to compare with choroidal thickness measured in Brazilian patients with diabetic macular edema (DME), neovascular age-related macular degeneration (AMD) and high myopia. Methods: A retrospective analysis of spectral domain optical coherence tomography (SD-OCT) images of 181 Brazilian subjects. A total of 74 eyes were included in the normal control group, 50 eyes in the nvAMD group, 44 eyes in the DME group and 13 eyes in the high myopia group. CT was measured from the posterior edge of the retinal pigment epithelium (RPE) to the choroid/sclera junction at the fovea and at 500 μm intervals temporal and nasal to the fovea. All measurements were performed by two independent observers and were averaged for analysis. The statistical analysis and comparison were performed using Mann Whitney (unpaired t-test). Results: Seventy-four eyes from 74 patients with a mean age of 51.4 years were analyzed in the normal group with a mean nasal, subfoveal and temporal choroidal thickness measurements were 301.30 ± 12.86 μm, 311.61 ± 12.62 μm and 309.28 ± 12.28 μm respectively. All groups with disease demonstrated a statistically significant choroidal thinning when compared with matched-aged normal eyes. The mean reduction in the nvAMD group compared to normal were 60.65 μm nasally, 59.77 μm temporally and 56.59 μm at subfoveal position. In the DME group, the subfoveal reduction was 51.10 μm, 63.03 μm and 46.30 μm, nasally and temporally. The patients with high myopia presented the greatest reduction in CT compared to normal eyes, with a mean reduction of 159.9 nasal, 159.98 subfoveal and 154.65 at temporal. Conclusions: The present study evaluated choroidal thickness in Brazilian subjects, with intense miscegenation. The results demonstrated a statistically significant decrease of the choroidal thickness in all subtypes of chorioretinal disease. The small sample size in this study was a limitation. Additional research with a larger study population to better understand these findings.