Intraocular Pressure Fluctuations Linked With Visual Field Loss in Advanced Glaucoma

Intraocular pressure (IOP) fluctuations increase the risk of visual field progression of advanced primary open-angle glaucoma (POAG), even when a low average IOP is maintained, according to research published in the Journal of Glaucoma.

Investigators conducted a retrospective analysis to identify risk factors associated with progression of visual field defects in advanced POAG. The review took into account 122 eyes of 122 patients with advanced POAG and any associations between clinical characteristics and visual field progression (defined as a deterioration of 3 or more visual field locations more than baseline at 5% levels in 4 consecutive visual fields with 24-2 Swedish interactive thresholding algorithm [SITA] testing).

The participants were monitored using Goldmann applanation tonometer, standard automated perimetry, cirrus optical coherence tomography, and fundus photography at 6-month intervals. The average follow-up duration was 100.7±44.2 months.

In total, 36 eyes (29.5%; patient mean age, 51.9±13.9 years) showed visual field progression, and 86 eyes (70.5%; patient mean age, 53.5±13.5 years) showed no progression. 

Patients with progression had greater long-term IOP fluctuations (2.6±1.4 mm Hg vs 2.0±1.0 mm Hg; P =.008) and more frequent disc hemorrhage (40.5% vs 17.4%; P =.005) than patients without progression. 

In a multivariate Cox regression analysis adjust for age, sex, average IOP and underlying hypertension, long-term IOP fluctuations (hazard ratio [HR], 2.57; P =.012) and disc hemorrhage (HR 2.35; P =.024) were identified as independent risk factors of visual field progression. Patients with both disc hemorrhage and long-term IOP fluctuations had the highest risk of progression (HR, 2.68; P =.035).

“Disc hemorrhage and long-term IOP fluctuations are independent and additive risk factors of visual field progression in advanced POAG,” researchers report. “Patients with advanced nerve damage and field loss, especially those in whom these factors are recognized, need vigorous treatment and close monitoring.”

Limitations of the study included the retrospective design, an entirely Korean patient population referred to a tertiary glaucoma clinic for specialized management, a relatively small number of patients, potential impacts of visual field test sensitivity fluctuations on the accuracy of visual field assessments, possible exclusion of patients with high false-negative rates due to advanced damage and low sensitivity, and the inability of the progression criteria adopted by the study to distinguish depression in the central and peripheral visual fields. 

Reference

Lee JS, Park S, Seong GJ, et al. Long-term intraocular pressure fluctuation is a risk factor for visual field progression in advanced glaucoma. J Glaucoma. Published online March 11, 2022. doi:10.1097/IJG.0000000000002011