Identifying Rapid Glaucoma Progression Using Hemifield Rates of Progression.

Abstract

Hemifield rates of progression are more sensitive to focal progression (or faster progression) than global rates. This can aid in tailoring management and treatment decisions. To determine if the rate of progression (ROP) of each hemifield of the 24-2 visual field (VF) aids in the detection of rapidly progressing eyes. In this retrospective longitudinal study, we evaluated 1658 eyes of 1658 consecutive glaucoma patients with global mean deviation (MD) VF loss between -3 and -15dB at baseline and ≥8 reliable VF tests (Swedish Interactive Thresholding Algorithm 24-2) with over ≥3 years of follow-up. The ROP (dB/year) based on global MD, superior hemifield MD, and inferior hemifield MD was calculated. The worst hemifield ROP (ROPworst) and hemifield ROP absolute difference (ROPdiff) were determined for each eye. Eyes were categorized based on the ROP from each metric as slow (-0.5dB/year or better), rapid (worse than -0.5dB/year), very rapid (worse than -1.0dB/year), and catastrophic (worse than -2.0dB/year) progression. The rate of significant asymmetric hemifield progression rate (ROPdiff ≥0.5dB/year) was also evaluated. On average, ROPworst was faster than ROPglobal by 0.25±0.3dB/year ( P <0.001). Based on ROPworst, 422 eyes (25%) were classified as progressing more rapidly than the ROPglobal classification. Over 40% (153/339) of the eyes classified as rapid progressors by ROPglobal were classified as very rapid or catastrophic progressors based on ROPworst. Eyes that progressed more rapidly based on ROPworst also had a higher rate of asymmetric progression. Hemifield ROPs are more sensitive to focal progression (or faster progression) than global rates and can aid in tailoring management and treatment decisions.