Difference in morning and evening choroidal thickness in Japanese subjects with no chorioretinal disease.
OBJECTIVE
To determine whether the choroidal thickness varies significantly according to the time of measurement in Japanese subjects without chorioretinal diseases.


METHODS
Twelve eyes of 12 subjects were examined with enhanced depth imaging spectral-domain optical coherence tomography. The choroidal thickness was measured in the mornings (9:00 to 9:30 AM) and evenings (7:30 to 8:00 PM) at three locations: the fovea, 1.5 mm temporal to the fovea, and 1.5 mm nasal to the fovea.


RESULTS
The mean age of the subjects was 62.6 ± 14.5 years. For the morning measurements, the mean choroidal thickness was 308.5 ± 74.4 μm at the fovea, 276.2 ± 84.6 μm temporally, and 239.3 ± 98.4 μm nasally. For the evening measurements, the mean choroidal thickness was 328.8 ± 85.6 μm at the fovea, 284.8 ± 91.6 μm temporally, and 248.9 ± 101.5 μm nasally. The mean subfoveal (P < .0001) and nasal (P = .03) choroidal thicknesses were significantly thicker in the evenings than in the mornings. There was no significant difference in the mean temporal choroidal thickness (P = .08).


CONCLUSIONS
The choroidal thickness varies according to the time of measurement.
Nagata Eye Clinic, Nara, Japan. noritama0620@topaz.ocn.ne.jp
Noriko
N
Toyokawa
Hideya
H
Kimura
Atsuko
A
Fukomoto
Shinichiro
S
Kuroda
D000328:Adult; D000368:Aged; D044466:Asian People; D002829:Choroid / Q000033:anatomy & histology*; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D041623:Tomography, Optical Coherence / Q000379:methods