Abstract
Purpose: :
To examine peripapillary choroidal thickness (ChTh) in patients with open angle glaucoma and ocular hypertension compared to healthy controls using spectral-domain optical coherence tomography (SD-OCT) and enhanced depth imaging (EDI).
Methods: :
127 healthy controls, 61 patients with ocular hypertension and 125 glaucoma patients were included in the study. Additional to a detailed standardized glaucoma examination all patients and healthy volunteers were investigated by SD-OCT with EDI (Spectralis HRA+OCT, Heidelberg Engineering, Germany). Circular B-scans (3.4 mm diameter, 768 A-scans, 16 sweeps) around the disc were obtained. Raw data were exported and the outer border of the retinal pigment epithelium and the inner scleral border were segmented using a customised software tool and a semiautomatic approach. ChTh was calculated based on exported segmentation values and mean circular thickness was calculated for further statistical analysis. 22 images could not be used because the choroidalscleral interface was not clearly visible on the whole circular scan.
Results: :
Peripapillary ChTh was correlated inversely with age (r = -0.432, p<0.001). Mean ChTh decreased from 139.9 ± 50.6 µm in the control group compared to 114.8 ± 41.3 µm (p=0.001) for early glaucoma (glaucomatous optic disc damage, normal visual field) and 109.1 ± 42.7 µm (p<0.001) for advanced glaucoma (glaucomatous optic disc damage, glaucomatous visual field damage). Differences remained significant if subgroups were matched for age. No differences concerning peripapillary ChTh were found between healthy controls and patients with ocular hypertension (137.9 ± 43.4 µm; p=0.792).
Conclusions: :
ChTh can be measured in vivo using SD-OCT and EDI in majority of patients. Peripapillary measurements demonstrated a high interindividual variability but showed a significant negative correlation with age. ChTh was reduced in glaucoma patients independently from age related changes.
Keywords: imaging/image analysis: clinical • choroid • aging