Table 2.
Photoreceptor outer segment layer thickness at different locations in healthy volunteers and in patients with diabetes, diabetic retinopathy, or diabetic retinopathy with macular edema.
| Groups | Mean subfoveal PROS thickness (μm) (range) | Mean nasal PROS thickness (μm) (range) | Mean temporal PROS thickness (μm) (range) |
|---|---|---|---|
| Healthy(60 eyes) | |||
| 1st OCT image | 38.5 ± 2.5 (29–43) | 27.3 ± 2.0 (24–34) | 27.4 ± 1.9 (23–32) |
| 2nd OCT image | 38.6 ± 5.5 (30–43) | 27.0 ± 1.7 (24–32) | 27.1 ± 2.2 (21–34) |
| DM without DR (36 eyes) | |||
| 1st OCT image | 38.2 ± 3.1 (28–43) | 26.9 ± 1.9 (23–31) | 27.1 ± 2.2 (23–25) |
| 2nd OCT image | 38.2 ± 4.6 (17–42) | 26.9 ± 2.5 (23–32) | 27.2 ± 2.2 (23–33) |
| DR (27 eyes) | |||
| 1st OCT image | 35.6 ± 4.4 (22–41) | 26.8 ± 3.4 (16–31) | 27.0 ± 2.5 (22–32) |
| 2nd OCT image | 36.1 ± 4.4 (28–47) | 26.3 ± 3.5 (12–31) | 26.8 ± 2.5 (22–31) |
| DR with DME (33 eyes) | |||
| 1st OCT image | 32.6 ± 6.9 (19–50) | 27.2 ± 4.2 (18–40) | 26.7 ± 6.0 (15–39) |
| 2nd OCT image | 32.6 ± 5.7 (17–44) | 26.7 ± 3.2 (22–35) | 28.0 ± 4.7 (19–37) |
| p value for ANOVA test | |||
| 1st OCT image | < 0.001* | 0.3 | 0.7 |
| 2nd OCT image | < 0.001* | 0.7 | 0.5 |
Abbreviations: OCT; optical coherence tomography; DM, diabetes mellitus; DR, diabetic retinopathy; DME, diabetic macular edema; PROS: photoreceptor retinal photoreceptor outer segment; μm, micrometer.
*
Bold values indicate statistical significance.