Table 3.
Comparison of Arterial and Venous Oxygen Saturation (SO2A and SO2V), Oxygen Extraction Fraction (OEF), Vessel Density (VD), and Vessel Tortuosity Index (VTI) Among Groups
| Control | No DR | Mild NPDR | Moderate to Severe | PDR | ||
|---|---|---|---|---|---|---|
| Metric | (N = 25) | (N = 28) | (N = 21) | NPDR (N = 14) | (N = 7) | P Value |
| SO2A (%) | 89 ± 7 | 94 ± 8 | 94± 10 | 95 ± 8 | 104 ± 12 | 0.002 |
| SO2V (%) | 53 ± 8 | 58 ± 9 | 56 ± 10 | 64 ± 13 | 64 ± 9 | 0.004 |
| OEF | 0.41 ± 0.08 | 0.39 ± 0.08 | 0.40 ± 0.10 | 0.33 ± 0.12 | 0.38 ± 0.08 | 0.07 |
| VD | 0.49 ± 0.04 | 0.48 ± 0.03 | 0.47 ± 0.05 | 0.45 ± 0.04 | 0.43 ± 0.05 | 0.003 |
| VTI | 0.50 ± 0.15 | 0.53 ± 0.14 | 0.51 ± 0.13 | 0.62 ± 0.18 | 0.55 ± 0.18 | 0.22 |
Data presented in control, no diabetic retinopathy (no DR), mild nonproliferative diabetic retinopathy (mild NPDR), moderate to severe NPDR, and proliferative diabetic retinopathy (PDR) groups.
Bolded values indicate P < 0.05.