Abstract
Purpose: :
To measure macular choroidal thickness in normal eyes at different points using enhanced depth imaging (EDI) optical coherence tomography (OCT) and to evaluate the association of choroidal thickness and age.
Methods: :
EDI OCT images were obtained in patients without significant retinal or choroidal pathology. The images obtained by positioning a spectral domain OCT device close enough to the eye to acquire an inverted image. Seven sections were obtained within a 5 x 30-degree area centered at the fovea, with 100 scans averaged for each section. The choroid was measured from the outer border of the retinal pigment epithelium to the inner scleral border at 500 micron intervals of a horizontal section from 3 mm temporal to the fovea to 3 mm nasal to the fovea. Statistical analysis was performed to evaluate variations of choroidal thickness at each location, and to correlate choroidal thickness and patient age.
Results: :
The mean age of the 30 patients (54 eyes) was 50.4 years (range 19 to 85 years), and 14 patients (46.7%) were female. The choroid was thickest underneath the fovea (mean 287 µm, standard deviation [±] 76 µm). Choroidal thickness decreased rapidly in the nasal direction, andaveraged 145 µm (± 57 µm) 3 mm nasal to the fovea. Increasing age was significantly correlated with decreasing choroidal thickness at all points measured. Regression analysis suggested that the subfoveal choroidal thickness decreased by 15.6 µm for each decade of life.
Conclusions: :
Choroidal thickness appears to vary topographically within the posterior pole. The thickness of the choroid showed a negative correlation with age. The decrease in the thickness of the choroid may play a role in the pathophysiology of various age-related ocular conditions.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • choroid • anatomy