Association of contrast sensitivity with vessel density and functional parameters in different stages of glaucoma

Purpose To evaluate the association between contrast sensitivity (CS), vessel density (VD), and functional parameters in patients with glaucoma of varying severity. Methods Ninety-four eyes of 94 patients (57 men and 37 women, aged 56.52 +/- 11.28 years) were divided into mild and moderate to advanced glaucoma groups. The mild glaucoma group was further subdivided based on the presence of central visual field defect (CVFD). Pearson's correlations were used to evaluate the associations between area under the log CS function (AULCSF), best-corrected visual acuity (BCVA), 10 - 2 visual field (VF), and structural parameters, including VD. The area under the receiver operating characteristic (AUROC) curve was calculated to detect abnormal CS (AULCSF < 1.2). Results In mild glaucoma without CVFD, AULCSF was associated with radial peripapillary capillary VD (gamma = 0.597, P = 0.001), with an AUROC of 0.840 (P = 0.006) for detecting abnormal CS. In mild glaucoma with CVFD, AULCSF worsened and was associated with superficial parafoveal VD (gamma = 0.569, P = 0.017) and macular whole image VD (gamma = 0.632, P = 0.007), with AUROCs of 0.833 (P = 0.021) and 0.792 (P = 0.043), respectively. In moderate to advanced glaucoma, the relationship between AULCSF and the mean deviation of 10 - 2 VF and BCVA was more robust than that observed in structural measures. Conclusions Decreased VD is linked to early CS impairment. Radial peripapillary capillary and macular VD can serve as indicators of CS function in the early stages of glaucoma.