Table 2.

Retinal artery variables measured by AO camera.

Variables	Control	NDR	M-NPDR	S-NPDR	PDR	p value
External diameter (μm)	120.12 ± 14.67	122.57 ± 18.60	122.93 ± 13.20	119.06 ± 11.16	122.69 ± 11.07	0.714
Lumen diameter (μm)	94.62 ± 11.95	93.21 ± 15.37	91.60 ± 11.37	89.35 ± 9.64	82.31 ± 11.74	0.001
Wall thickness (μm)	25.58 ± 3.80	29.36 ± 4.88	31.33 ± 6.24	29.70 ± 2.82	40.35 ± 5.74	< 0.001
Wall to lumen ratio	0.27 ± 0.03	0.31 ± 0.04	0.34 ± 0.07	0.33 ± 0.03	0.50 ± 0.11	< 0.001