In Japanese patients with primary open-angle glaucoma (POAG), more frequent disc hemorrhages at the site of structural progression may be a significant contributor to a shorter disease progression time, a study in the Journal of Glaucoma suggests. This indicates disc hemorrhage may reflect vulnerability to same-site structural deterioration, the researchers add.
The three-year prospective study also found the relationship between disc hemorrhage and retinal nerve fiber layer (RNFL) defects and the pattern of RNFL defect progression differed by disc location.
The prospective cohort study included individuals with POAG who had intraocular pressure of 18mm Hg or less and were being treated with prostaglandin analog monotherapy.
The researchers took fundus photographs at baseline and every three months over a three-year period and determined disc hemorrhage and structural progression independently by flicker chronoscopy. The investigators noted any clock-hour disc locations in the right eye format and determined co-localization.
Among 195 eyes of 115 patients, disc hemorrhage appeared in 85 sites in 65 eyes (33.3%) and was most frequently at the seven o’clock disc location (29.4%). Structural progression occurred at 63 sites of 52 eyes (26.7%) comparably in both superior and inferior hemi-discs, which was mostly detected as widening of the RNFL defects.
Temporal RNFL defect widening was common, while nasal widening occurred exclusively in the vertical quadrants.
Of 41 progression sites in eyes with disc hemorrhage, 28 sites (68.2%) had both disc hemorrhage and progression.
The researchers also found progression sites with disc hemorrhage were less common in the superior quadrant than in the inferior and temporal quadrants.
Additionally, eyes with disc hemorrhage were nearly four times more likely to progress than those without disc hemorrhage.
Of note: in 63 progression sites, disc hemorrhage recurrence and a greater number of disc hemorrhages at the progression site were significantly associated with shorter time to progression from baseline, while co-localization of disc hemorrhage and progression were not.
Higashide T, Ohkubo S, Udagawa S, et al. Spatial and temporal relationship between structural progression and disc hemorrhage in glaucoma in a three-year prospective study. Ophthalmology Glaucoma. August 21, 2020. [Epub ahead of print].