Choroidal Thickness and its Correlations with Ocular Parameters in Primary Open-angle Glaucoma

Abstract

Objectives: To evaluate the relationships between macular choroidal thickness (mCT) and ocular parameters, such as optic nerve head (ONH) and multifocal electroretinogram (mf-ERG) parameters, in cases with primary open-angle glaucoma (POAG).

Methods: This controlled and prospective clinical trial included 49 patients with POAG diagnosed for the fırst time and 47 healthy participants. Macular CTs, ONH and mf-ERG parameters were measured, and the examination findings were recorded at baseline and follow-ups.

Results: In the POAG group, the mean mCT was 254.92±37.65 µm at baseline, and it was 235.6±38.48 µm at 3-month and was 237.55±37.27 µm at 6-month. In the glaucoma group, there was a significant decrease in the first three months despite the treatment, but no significant change was observed in the next three months. In the healthy group, the mean mCTs were 287.78±26.77 µm, 285.48±25.58 µm and 285.02±27.44 µm at baseline, at 3-month and at 6-month, respectively. No significant change was observed in the control group throughout the process. However, the mean mCT values in the glaucoma group were significantly thinner in all controls compared to the healthy group (p<0.05). Furthermore, significant correlations were found between CT and some ONH, as well as mf-ERG parameters.

Conclusion: The choroid can play an important role in the pathogenesis of glaucoma. Significant correlations in parameters support this relationship. We have observed that the glaucomatous effect initiated first in the inferior quadrant of ONH.

Keywords: Enhanced depth imaging optical coherence tomography; macular choroidal thickness; multifocal electroretinogram; optic nerve head; primary open-angle glaucoma.

Figure 1

The mean macular choroidal thicknesses in the primary open-angle glaucoma and the healthy groups during the study. POAG=primary open-angle glaucoma; Repeated measures ANOVA test showed significant decreases only in the POAG group from baseline to 6-month. (#p>0.05, *p<0.05).