Purpose: To investigate the relationship between peripapillary choroidal thickness (PCT) and choroidal vascular prominence (CVP) colocalized with retinal nerve fiber layer (RNFL) defect in primary open-angle glaucoma (POAG) eyes and to evaluate the relationship between PCT and POAG severity.
Methods: In this cross-sectional comparative study, 29 POAG patients with CVP on RNFL imaging (Group A), 70 POAG patients without CVP (Group B) and 63 healthy controls (Group C) were examined. Various factors including age, intraocular pressure (IOP), spherical equivalent (SE), axial length (AXL), central corneal thickness (CCT), peripapillary RNFL thickness, visual-field mean deviation (MD) and pattern standard deviation (PSD) were investigated. Also, PCT (average, clock-hour) was measured by swept-source optical coherence tomography. The differences in each of the factors were analyzed among the groups.
Results: There was no significant difference in age, IOP, SE, AXL or CCT among the three groups (P > 0.05). MD, PSD and RNFL thickness (RNFLT) in Groups A and B were lower than in Group C, but there was no difference between Groups A and B. There was a significant difference in adjusted PCT between Groups A and B (79.39 ± 6.56 vs. 115.87 ± 4.25, P < 0.001). Every adjusted clock-hour PCT in Group A was significantly thinner than in Group B.
Conclusions: CVP in red-free RNFL images indicated severe thinning of PCT. Although PCT thinning was not related to glaucoma severity, CVP in red-free RNFL images should be observed as an indicator of PCT thinning, associated with POAG.
Keywords: Choroidal vascular prominence; Glaucoma; Peripapillary choroidal thickness; Red-free retinal nerve fiber layer image.