Table 2.
Fractal dimension of the thickness maps of retinal layers in Alzheimer disease patients and control groups.
| Retinal layer | AD group FD mean ± SD |
Control group FD mean ± SD |
FD difference (AD – CTL) × 103 | Mann–Whitney | |
|---|---|---|---|---|---|
| U | p value | ||||
| 1. NFL | 2.1074 ± 0.0057 | 2.1018 ± 0.0040 | 5.6 | 552 | 0.000 |
| 2. GCL | 2.1033 ± 0.0083 | 2.1012 ± 0.0061 | 2.1 | 458 | 0.168 |
| 3. IPL | 2.1136 ± 0.0069 | 2.1110 ± 0.0060 | 2.6 | 472 | 0.096 |
| 4. INL | 2.1105 ± 0.0080 | 2.1078 ± 0.0067 | 2.8 | 470 | 0.105 |
| 5. OPL | 2.1180 ± 0.0076 | 2.1169 ± 0.0084 | 1.1 | 432 | 0.372 |
| 6. ONL | 2.0939 ± 0.0088 | 2.0885 ± 0.0087 | 5.3 | 491 | 0.038 |
| 7. IS/OS | 2.1281 ± 0.0081 | 2.1278 ± 0.0067 | 0.3 | 419 | 0.495 |
| 8. OSL | 2.1217 ± 0.0103 | 2.1219 ± 0.0075 | − 0.2 | 443 | 0.276 |
| 9. OPR | 2.1230 ± 0.0106 | 2.1219 ± 0.0053 | 1.1 | 474 | 0.088 |
| 10. RPE | 2.1269 ± 0.0071 | 2.1232 ± 0.0043 | 3.7 | 499 | 0.024 |
| Total Retina | 2.0782 ± 0.0105 | 2.0800 ± 0.0085 | -1.7 | 384 | 0.799 |
Statistically significant differences (p < 0.05) and the corresponding layer names appear in boldface.
AD Alzheimer’s disease, FD fractal dimension, SD standard deviation, CTL control (group), NFL nerve fiber layer, GCL ganglion cell layer, IPL inner plexiform layer, INL inner nuclear layer, OPL outer plexiform layer, ONL outer nuclear layer, IS/OS inner segment/outer segment layer, OSL outer segment layer, OPR outer segment PR/RPE complex, RPE retinal pigment epithelium.