Relationship of intraocular pressure and frequency of spontaneous retinal venous pulsation in primary open-angle glaucoma

Abstract

Purpose: To investigate the relationship of intraocular pressure (IOP) and the frequency of spontaneous venous pulsation (SVP) in primary open-angle glaucoma (POAG).

Design: Cross-sectional study.

Participants: A total of 229 eyes of 229 patients with POAG and 205 eyes of 205 glaucoma suspects as a control.

Methods: The SVP was assessed using a confocal scanning laser ophthalmoscope (Spectralis HRA, Heidelberg Engineering, Heidelberg, Germany) movie tool. Patients with POAG were divided into 3 groups on the basis of the frequency distribution of untreated IOP: lower tertile (IOP ≤ 15 mmHg; group A), middle tertile (IOP >15 and ≤ 21 mmHg; group B), and upper tertile (IOP >21 mmHg; group C). The frequency of SVP was compared between the glaucoma suspects and patients with POAG and among the 3 groups of POAG. Logistic regression analysis was performed to determine the factors associated with the frequency of SVP.

Main outcome measures: Frequency of SVP in patients with POAG and glaucoma suspects.

Results: Spontaneous venous pulsation was more frequently found in glaucoma suspects than in patients with POAG (86.3% vs. 53.3%, P<0.0001). Within the POAG group, the frequency of SVP was significantly lower in group A (40.2%) than in group B (57.3%, P = 0.03) and group C (63.9%, P = 0.003). There was no significant difference between groups B and C (P = 0.42). In addition to IOP (P = 0.007), visual field mean deviation (MD) and refractive error were associated with the frequency of SVP (P<0.0001 and P = 0.011, respectively). When analyzed within the same stage of disease, SVP was less frequently found in group A than in group C in early (P = 0.011) and advanced (P = 0.044) glaucoma and marginally less frequently found in moderate glaucoma (P = 0.080).

Conclusions: Spontaneous venous pulsation was less common in patients with POAG than in glaucoma suspects. Among the patients with POAG, SVP was less common in patients with low IOP at all stages of disease. These results are consistent with vascular factors having a more significant role in patients with POAG with low IOP than in patients with POAG with higher IOP.