Purpose:
To determine the prevalence of parapapillary RBV change over time in a cohort of patients with glaucoma and variable rates of perimetric and structural progression.
Methods:
Baseline and follow up serial stereophotographs from one eye of a cohort of consecutive patients with >8 reliable SITA-Standard visual fields were included. Based on global rates of absolute threshold sensitivity change, each patient was categorized as being a rapid (-0.65 dB/y and higher), moderate (-0.02 to -0.65 dB/yr), or slow (less than -0.02 dB/yr) progressor. Negative controls consisted of 33 patients with baseline and follow up photos taken on the same day. A grader masked to progression status reviewed serial photographs aligned with automated alternation flicker (EyeIC, Narbeth, PA) for the presence of any discrete extrapapillary RBV changes. The grader was instructed to identify changes in the contour or position of RBVs in comparison to either the underlying choroidal vasculature or to adjacent retinal features (e.g., drusen, other retinal vessels) and to distinguish RBV movement from global vessel change associated with image parallax and from isolated RBV caliber change seen with arteriovenous pulsation. The presence or absence of disc hemorrhage (DH) and parapapillary atrophy (PPA) progression was also recorded. To determine agreement with neuroretinal rim loss, photographic sets in which two separate graders masked to the study design agreed upon neuroretinal rim loss were compared to those with RBV movement.
Results:
Of 158 included patients, the grader identified 39 (24.7%) eyes that met the above criteria for RBV movement. RBV movement occurred in 33.7% of patients with moderate or rapid progression and in 12.1% of patients with no or slow progression (p=0.002). On comparison to structural progression, RBV movement occurred in 88.2% with progressive neuroretinal rim loss (n=17) vs. 17.0% without rim loss (n=141; p<0.001). RBV movement also occurred in 58.8% with PPA progression vs. 15.3% without PPA progression (p<0.001) and in 64.2 % with DH vs. 20.8% without DH (p<0.001).
Conclusions:
RBV movement occurs in eyes with progressive glaucoma and is associated with structural and functional progression as well as other markers of progression, such as PPA progression and DH. This is a new clinical finding that could help identify rapid glaucoma progression.
Keywords: optic nerve • retina • visual fields