Subfoveal choroidal thickness in Caucasians

Purpose Purpose: To examine the normal thickness of the subfoveal choroid and associated factors. Methods Methods: Patients without any macular or optic nerve disease and attending the clinic for cataract surgery underwent biometry and enhanced depth imaging of the deep retinal and choroidal layers by spectral domain optical coherence tomography (SD‐OCT, Spectralis). Results Results: The study included 47 patients (24 women) with a mean age of 73.4 ± 7.3 years (range: 57.1 – 87.4 years) and mean axial length of 23.56 ± 0.88 mm (range: 21.65 – 25.47mm). In multivariate analysis, mean choroidal thickness (253 ± 103µm; mean: 241µm; range: 94‐573µm) decreased significantly with longer axial length (non‐standardized correlation coefficient B: ‐0.46; standardized correlation coefficient ß= ‐0.39; P =0.006) and older age (B: ‐4.4; ß= ‐0.31; P=0.03). Conclusion Conclusions: Mean subfoveal choroidal thickness in elderly Caucasians was 253 ± 103µm. For each mm increase in axial length, and for each increase in year of age, subfoveal choroidal thickness decreased by 46µm and 4.4µm, respectively. These data are almost identical with those measured for Chinese in the Beijing Eye Study (mean thickness: 254±107μm; decrease in choroidal thickness by 45μm and 4.1μm for each mm increase in axial length and each year increase in year of age, resp.)