Abstract
Purpose :
To investigate whether the position of the central retinal vascular trunk, as a surrogate of lamina cribrosa (LC) deviation, was associated with the presence of glaucoma in unilateral open-angle glaucoma (OAG) patients.
Methods :
One hundred twenty-nine (129) subjects with unilateral OAG were included in this cross-sectional study. The position of the vascular trunk was measured as the deviation from the center of the Bruch’s membrane opening (BMO), as delineated by OCT imaging. The shift index was calculated as the distance of the vascular trunk from the BMO center relative to that of the BMO margin. The angular deviation of vascular trunk was measured with the horizontal nasal midline as 0° and the superior location as a positive value. The shift index and angular deviation were compared between glaucoma and fellow control eyes within individuals. The angular location of the midpoint of the retinal nerve fiber layer (RNFL) defect was measured from the BMO center. Shift index was compared between OAG eye and fellow eye.
Results :
OAG eyes had higher baseline IOP (14.9 ± 3.7 mmHg vs. 14.2 ± 2.8 mmHg, P < 0.001), a larger β-zone parapapillary atrophy area (1.01 ± 0.70 mm2 vs. 0.88 ± 0.67 mm2, P = 0.001), and a larger shift index (0.55 ± 0.28 vs. 0.37 ± 0.22, P < 0.001). In a generalized linear mixed-effects model, larger shift index was the only risk factor of OAG diagnosis (OR = 8.705, P = 0.001). A generalized estimating equation regression model revealed that the shift index was larger in the OAG eyes than in the control eyes for all ranges of axial length, while it was the smallest for the axial length of 23.7 mm (all P < 0.001).
Conclusions :
The shift index was larger in the unilateral OAG eyes, which fact is suggestive of the potential role of LC deviation as a locoregional susceptibility factor.
This is a 2020 ARVO Annual Meeting abstract.