A Study on the Central Corneal Thickness of Primary Angle Closure and Primary Angle Closure Glaucoma and Its Effect on Visual Field Progression

PURPOSE: To determine the mean central corneal thickness (CCT) and the relationship between the CCT and visual field progression in primary angle closure (PAC) and primary angle closure glaucoma (PACG).

DESIGN: A combined cross-sectional and prospective study on PAC and PACG.

METHODS: A total of 35 eyes were included in the study for each group of normal control, PAC, and PACG patients from eye clinics in Kota Bharu, state of Kelantan, Malaysia, from January 2007 to November 2009. The PAC and PACG patients were divided into thin and thick CCT groups. They were followed up for 12 to 18 months for visual field progression assessment with their mean Advanced Glaucoma Intervention Study (AGIS) score.

RESULTS: The CCT was 516.8 ± 26.0 µm for PAC and 509.7 ± 27.4 µm for PACG. Both were significantly thinner compared with the control group with CCT of 540 ± 27.8 µm (P < 0.001). There was a statistically significant increase in the mean AGIS score after 12.9 ± 1.7 months of follow-up in the thin CCT group for PACG (P = 0.002). However, no significant increase in the mean AGIS score was found for the thick CCT group in PACG and for both thin and thick CCT in PAC.

CONCLUSIONS: The PAC and PACG had statistically significant thinner CCT compared with the controls. Thin CCT was associated with visual field progression based on the mean AGIS score in PACG.