Mehmet Giray ERSÖZ, İbrahim ÖZDEMİR, Sucattin İlker KOCAMIŞ

Comparison of the long-term effects of high and low altitude on the choroidal thickness

The aim is to evaluate the long-term effects of high and low altitudes on the choroid. This study was a cross-sectional retrospective study. The individuals were divided into two groups according to the altitude where those lived. Those living at low altitude (Sakarya) were included in the low altitude group (LAG), and those living at high altitude (Ağrı) were included in the high altitude group (HAG). Sub-foveal choroidal thicknesses of both groups were compared. Spectral domain optical coherence tomography (SD-OCT) was used to measure the subfoveal choroidal thickness. The average of subfoveal CT in LAG was 270.3±22.2μm, whereas it was 275.1±21.0 μm in HAG. No significant difference in choroid thickness was observed in between the groups ( P= 0.334).The choroid may have the ability to autoregulate and maintain a constant blood flow to the retina under different conditions.

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