Purpose: To assess the correlation between central corneal thickness (CCT) and anterior scleral thickness (AST) in Korean patients with normal tension glaucoma (NTG) and primary open angle glaucoma (POAG).
Patients and methods: Consecutive patients with POAG, NTG, and normal individuals were recruited. Anterior segment optical coherence tomography (AS-OCT, Visante) was used to measure CCT and AST. The AST was measured 2 mm posterior to the scleral spur in the temporal meridian. Statistical analysis of the data included ANOVA and Pearson correlation analysis.
Results: One hundred and eight participants (36 with NTG, 35 with POAG, and 37 normal individuals) were enrolled. The CCT (NTG 514.8 1± 25.03 μm; POAG 534.43 ± 34.79 μm; controls 536.70 ± 32.11 μm) was found to be thinner in patients with NTG compared with POAG and the control eyes (P=0.023; P=0.009). The AST (NTG 738.53 ± 53.63 μm; POAG 771.86 ± 53.75 μm; controls 783.62 ± 57.03 μm) was thinner in the patients with NTG compared with POAG and the normal controls (P=0.032; P=0.002). No significant difference in AST was found among the POAG and control eyes (P=0.636). A correlation between CCT and AST was found only among the patients with NTG (r=0.469, P=0.004). However, no correlation was observed between CCT and AST in patients with POAG and controls.
Conclusions: Anterior scleral thickness was correlated with CCT in the NTG group, but this correlation was not observed among the POAG or control groups.