To investigate the correlation between central corneal thickness (CCT) and peripapillary retinal nerve fiber layer (RNFL) thickness in the eyes of patients with normal tension glaucoma (NTG) at the initial examination and to examine the difference in the degrees of damage of RNFL thickness depending on the CCT.

Fifty-one eyes of 36 patients with NTG were included in the study, and 51 eyes of 30 people without the disease were used as a control group. CCT and peripapillary RNFL thickness were measured in each eye by ultrasonic pachymetry and optical coherence tomography(OCT), respectively. Patients from the normal NTG group who underwent OCT more than three times inthree years were identically assigned to two groups based on CCT: thin (< 553.6 µm) and thick (≥ 553.6 µm). Thus, a comparison of the changes in the thickness of retinal nerve fiber layer was performed between the two groups.

Patients with NTG showed a significant positive correlation between CCT and the mean peripapillary RNFL thickness at the initial examination (R=0.68, p <0.01). There were no significant differences in the changes in thickness of RNFL between the groups based on CCT ( p >0.05)

At the time of initial diagnosis of NTG, there was a significant correlation between the thickness of CCT and RNFL. Howeverthere was no significant correlation between the thickness of CCT and the progression of the damage of RNFL.