We read with interest the article by Adhi and associates. The authors used spectral-domain optical coherence tomography (SD OCT) to analyze the choroidal thickness in eyes with Stargardt disease.
However, some issues that could influence the results of choroidal thickness measurement should be addressed. Firstly, the time of SD OCT imaging needs to be described. Choroidal thickness has a diurnal rhythm. Previous studies have found a mean maximum-minimum difference of 29-59.4 μm over a 24-hour period. Secondly, in addition to age and sex, axial length is another important factor that influences choroidal thickness, which should be considered in Adhi and associates’ study.
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- 3. Chakraborty R., Read S.A., and Collins M.J.: Diurnal variations in axial length, choroidal thickness, intraocular pressure, and ocular biometrics. Invest Ophthalmol Vis Sci 2011; 52: pp. 5121-5129
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