[Enhanced depth imaging of the choroid in open-angle glaucoma: a preliminary study]. / Évaluation de l'épaisseur choroïdienne par tomographie en cohérence optique (SD-OCT). Étude préliminaire dans le glaucome à angle ouvert.

INTRODUCTION: Choroidal thickness (CT) can be evaluated with spectral domain OCT. The authors report the results from a preliminary study comparing CT in normal and glaucomatous eyes. PATIENTS AND METHOD: The aim of this study was to measure subfoveolar CT in normal and glaucomatous eyes and to evaluate the recent enhanced depth imaging technique (EDI SD-OCT). Seventeen eyes of nine healthy subjects where compared with 23 eyes of 14 glaucomatous patients. CT was evaluated using a Spectralis™ OCT. A section was obtained within a 30° scan centered on the fovea, with 100 scans averaged for each section. Two acquisitions were made for each eye by the same operator to obtain an average CT measurement. The results were compared with clinical examination data (refractive error, peripapillary atrophy, and age). RESULTS: There was a strong correlation between the two measurements r=0.99 (p<0.001). The mean age of the healthy group was 72.76±7.71 years, the mean refractive error was 0.71±0.74 D, and peripapillary atrophy was present in 29% of the eyes. The mean subfoveal CT was 224.38µm. The mean age of the glaucomatous group was 71.39±11.37, the mean refractive error was-1.37±2.74 D, and peripapillary atrophy was present in 70% of the eyes. The mean subfoveal CT was 219.98µm. There was no significant difference between the two populations for the subfoveolar CT or refractive errors. In both groups, there was a negative correlation between CT and peripapillary atrophy. In healthy eyes, peripapillary atrophy was correlated with age (p<0.001), whereas it was not in the glaucomatous population (p=0.795). DISCUSSION: This is the first study, to our knowledge, evaluating EDI OCT in glaucomatous eyes. Reproducibility was excellent. There was always a negative correlation between CT and peripapillary atrophy. There was no CT difference between the normal and glaucomatous group, but the number of patients was small. CONCLUSION: Further studies are required to evaluate the possible relationship between CT and peripapillary atrophy and the link with the evolutive stage of the glaucomatous neuropathy.