SD-OCT choroidal thickness in advanced primary open-angle glaucoma

PURPOSE: To assess the choroidal thickness in advanced primary open-angle glaucoma (POAG) comparing patients affected by advanced glaucoma and normal subject using spectral domain optical coherence tomography (SD-OCT). METHODS: In total, 35 eyes of 35 patients affected by POAG with advanced perimetric defect (mean deviation worse than -12 dB) were prospectively enrolled and underwent a complete ophthalmologic examination, including enhanced depth imaging SD-OCT. One eye of 35 healthy subjects served as control group. Choroidal thickness was measured at the subfoveal location, at 0.5, 1.0, and 2.0 mm nasal and temporal to the fovea. Primary outcome measure was the identification of different choroidal thickness between advanced glaucoma patients and normal subjects. RESULTS: Glaucoma and control group were homogenous for age, sex, and axial length (P>0.05 in all cases). A significant difference was found in the subfoveal choroidal thickness (SFCT) adjusted for age and axial length between glaucoma and control eyes (P=0.042); in glaucoma patients the mean adjusted SFCT was 209.90 μm compared with 234.78 μm in control subjects. Both temporal and nasal choroidal thickness measurements followed the same SFCT trend, even if only temporal ones were statistically significant. We also found that SFCT decreased with age and increased axial length (P=0.007 and 0.001, respectively). Sex and intraocular pressure did not significantly influence the choroidal thickness (P=0.87 and 0.35, respectively). CONCLUSIONS: Patients affected by advanced POAG damage have a thinner choroidal thickness compared with normal subjects, using SD-OCT. We also confirmed that age and axial length were the main factors affecting choroidal thickness in these patients.