Sector-specific association of intraocular pressure dynamics in dark-room prone testing and visual field defect progression in glaucoma

Purpose To investigate sectoral differences in the relationship between intraocular pressure (IOP) dynamics during dark-room prone testing (DRPT) and visual field (VF) defect progression in primary open-angle glaucoma (POAG) patients. Design Retrospective, longitudinal study Participants This retrospective study included 116 eyes of 84 POAG patients who underwent DRPT and had at least five reliable VF tests conducted over a more than two-year follow-up period. We excluded eyes with mean deviation worse than -20 dB or a history of intraocular surgery or laser treatment. Methods Average total deviation (TD) was calculated in the superior, central, and inferior sectors of the Humphrey 24-2 or 30-2 program. During DRPT, IOP was measured in the sitting position, and after 60 minutes in the prone position in a dark room, IOP was measured again. The relationship between IOP change during DRPT, IOP after DRPT, and TD slope in each quadrant was analyzed with a linear mixed-effects model, adjusting for other potential confounding factors. Main Outcome Measures TD slope in each quadrant, IOP change during DRPT, and IOP after DRPT Results IOP after DRPT and IOP change during DRPT were 18.16±3.42 mmHg and 4.92±3.12 mmHg, respectively. Superior TD slope was significantly associated with both IOP after DRPT (β=-0.28, p=0.003) and IOP change during DRPT (β=-0.21, p=0.029), while central (β=-0.05, p=0.595; β=-0.05; p=0.622) and inferior (β=0.05, p=0.611; β=0.01, p=0.938) TD slopes were not. Conclusion DRPT might be a useful test to predict the risk of superior VF defect progression in eyes with POAG.