TABLE 2.
Two-factors split-plot analysis of variance analysis
| Two-Factors Split-Plot ANOVA | ||||||||||
| PD N = 21 (41 eyes) |
ET N = 23 (42 eyes) |
HC N = 17 (33 eyes) |
Model F (P) |
Groups F (P) |
Eye F (P) |
Groups × Eye F (P) |
||||
| Right Eye | Left Eye | Right Eye | Left Eye | Right Eye | Left Eye | |||||
| RNFL (µm) | 13.6 ± 2.2 | 13.2 ± 1.6 | 15.0 ± 1.6 | 15.0 ± 1.7 | 17.9 ± 1.8 | 17.6 ± 2.5 | 19.76 (<0.001) | 48.98 (< 0.001) | 0.54 (0.463) | 0.11 (0.9) |
| GCL (µm) | 15.8 ± 3.4 | 16.4 ± 2.9 | 17.5 ± 3.7 | 17.6 ± 3.2 | 21.5 ± 2.3 | 21.4 ± 2.2 | 11.48 (<0.001) | 28.41 (<0.001) | 0.17 (0.684) | 0.11 (0.9) |
| IPL (µm) | 20.8 ± 3.5 | 21.9 ± 2.1 | 21.5 ± 3.2 | 22.7 ± 3.3 | 24.8 ± 1.6 | 23.6 ± 2.4 | 4.86 (<0.001) | 9.48 (< 0.001) | 0.5 (0.479) | 2.04 (0.135) |
| INL (µm) | 19.9 ± 6.5 | 21.6 ± 4.2 | 23.5 ± 5.4 | 23.5 ± 5.0 | 27.3 ± 4.7 | 29.1 ± 4.4 | 8.22 (<0.001) | 19.5 (<0.001) | 1.51 (0.222) | 0.39 (0.675) |
| OPL (µm) | 26.5 ± 6.8 | 30.5 ± 5.0 | 27.5 ± 5.9 | 28.4 ± 4.4 | 30.7 ± 3.2 | 31.7 ± 6.2 | 2.8 (0.02) | 3.71 (0.027) | 4.01 (0.05) | 1.13 (0.327) |
| ONL (µm) | 85.8 ± 15.6 | 86.4 ± 8.7 | 87.8 ± 10.3 | 86.9 ± 9.6 | 97.5 ± 7.0 | 97.9 ± 8.6 | 5.16 (<0.001) | 12.84 (<0.001) | 0.001 (0.99) | 0.05 (0.947) |
| RPE (µm) | 15.4 ± 1.9 | 15.7 ± 1.3 | 15.4 ± 1.6 | 16.0 ± 1.5 | 16.3 ± 1.8 | 16.2 ± 1.7 | 1.09 (0.368) | 1.77 (0.174) | 0.94 (0.334) | 0.37 (0.688) |
| pRNFL (µm) | 91.8 ± 10.4 | 93.8 ± 8.4 | 94.9 ± 10.3 | 96.0 ± 9.8 | 100.0 ± 6.8 | 102.3 ± 9.1 | 3.21 (0.01) | 7.48 (<0.001) | 1.07 (0.303) | 0.05 (0.951) |
| pRNFL superior (µm) | 109.8 ± 18.4 | 115.9 ± 14.0 | 114.0 ± 11.5 | 114.0 ± 11.2 | 119.6 ± 7.5 | 121.7 ± 11.5 | 1.99 (0.08) | 3.74 (0.027) | 1.27 (0.262) | 0.57 (0.565) |
| pRNFL temporal (µm) | 70.1 ± 9.6 | 70.8 ± 10.3 | 73.0 ± 7.3 | 72.4 ± 7.6 | 78.6 ± 8.7 | 77.9 ± 7.1 | 3.2 (0.01) | 7.88 (<0.001) | 0.01 (0.91) | 0.07 (0.929) |
| pRNFL inferior (µm) | 119.4 ± 15.3 | 121.0 ± 15.1 | 115.8 ± 11.7 | 115.2 ± 11.7 | 119.4 ± 8.0 | 119.3 ± 10.6 | 0.7 (0.627) | 1.66 (0.195) | 0.02 (0.901) | 0.08 (0.919) |
| pRNFL nasal (µm) | 73.9 ±11.1 | 72.0 ± 9.3 | 75.5 ± 9.0 | 75.1 ± 10.1 | 82.4 ± 6.0 | 79.3 ± 10.0 | 2.9 (0.017) | 6.55 (0.002) | 1.01 (0.317) | 0.19 (0.828) |
In bold: P < 0.05.
ANOVA, analysis of variance; ET, essential tremor; GCL, ganglion cell layer; HC, healthy controls; INL, inner nuclear layer; IPL, inner plexiform layer; ONL, outer nuclear layer; OPL, outer plexiform layer; PD, Parkinson disease; pRNFL, peripapillary RNFL; RNFL, retinal nerve fiber layer; RPE, retinal pigment epithelium.