Reproducibility of Scleral Spur Identification and Angle Measurements Using Fourier Domain Anterior Segment Optical Coherence Tomography

Table 2

Mean (± standard deviation) differences (𝜇m) in scleral spur landmark placement.

	All eyes; (𝑁=31); by 2 readers; (with adjudicator); (𝜇m)	Open-angle eyes; (𝑁=12); by 2 readers; (with adjudicator); (𝜇m)	Nonopen-angle eyes; (𝑁=19); by 2 readers; (with adjudicator); (𝜇m)
𝑥-axis difference
All quadrants	−16.5* ± 53.3; (−15.5 ± 41.8)	−22.0 ± 41.6; (−11.8 ± 47.0)	−13.0 ± 59.5; (−17.8 ± 38.3)
Horizontal
Nasal	−25.7 ± 71.9; (−19.7 ± 45.4)	−43.0 ± 52.0; (−30.0 ± 44.1)	−14.8 ± 81.5; (−13.2 ± 46.2)
Temporal	−8.7 ± 41.0; (−13.5 ± 35.2)	−13.0 ± 15.7; (−5.8 ± 33.6)	−6.0 ± 51.2; (−18.3 ± 36.3)
Vertical
Superior	−20.1 ± 49.7; (−6.8 ± 46.7)	−18.7 ± 45.6; (4.7 ± 59.9)	−21.1 ± 53.3; (−14.1 ± 36.0)
Inferior	−11.4 ± 46.2; (−22.0 ± 39.2)	−13.5 ± 41.4; (−16.0 ± 45.3)	−10.1 ± 50.0; (−25.8 ± 35.6)
𝑃value; (H versus V)	0.8597; (0.7646)	0.3283; (0.3632)	0.6162; (0.6198)
𝑦-axis difference
All quadrants	1.5* ± 52.8; (0.4 ± 47.6)	−8.0 ± 52.7; (−0.8 ± 59.2)	7.5 ± 52.4; (1.2 ± 39.0)
Horizontal
Nasal	−2.2 ± 50.5; (2.8 ± 43.7)	−14.6 ± 44.3; (−5.1 ± 33.5)	5.6 ± 53.7; (7.8 ± 49.3)
Temporal	10.3 ± 52.2; (5.5 ± 42.7)	10.9 ± 47.1; (13.7 ± 54.9)	9.9 ± 56.5; (0.4 ± 33.5)
Vertical
Superior	7.2 ± 45.4; (9.9 ± 45.6)	5.2 ± 51.2; (19.0 ± 64.2)	8.5 ± 42.7; (4.1 ± 29.4)
Inferior	−9.2 ± 62.1; (−16.0 ± 55.3)	−33.4 ± 60.9; (−30.8 ± 71.2)	6.0 ± 59.4; (−7.5 ± 42.1)
𝑃value; (H versus V)	0.5713; (0.3844)	0.4071; (0.5494)	0.9670; (0.5234)

*A negative mean difference indicates that observer 1 is closer to the center of the image.