Table 1 Optic nerve sheath, eyeball, and optic canal anterior (orbital) opening CT measurements (in mm)
Distance/position | Right eye | Left eye | ||||
|---|---|---|---|---|---|---|
Mean ± SD | Max | Min | Mean ± SD | Max | Min | |
Distal ONSD* | 4.94 ± 1.51 | 7.5 | 3.5 | 5.17 ± 1.34 | 7.9 | 3.8 |
Middle ONSD** | 4.35 ± 0.76 | 7.6 | 3.3 | 4.45 ± 0.62 | 5.9 | 3.3 |
Proximal ONSD*** | 3.84 ± 0.82 | 5.2 | 2.7 | 3.65 ± 0.70 | 4.8 | 2.9 |
Proximal ONS area | 11.58 ± 1.8 | 21.23 | 5.7 | 10.46 ± 1.5 | 18 | 6.6 |
Transverse | 22.822 ± 1.7 | 25.5 | 20.0 | 22.936 ± 1.8 | 25.8 | 19.4 |
Eyeball diameter | ||||||
Optic canal anterior opening | ||||||
Longer diameter | 4.8 ± 1.8 | 5.8 | 3.5 | 5.0 ± 1.8 | 5.8 | 3.6 |
Shorter diameter | 4.2 ± 1.6 | 4.8 | 2.9 | 4.2 ± 1.7 | 4.8 | 2.8 |
Area (mm2) | 15.83 ± 2.3 | 19 | 7.2 | 16.49 ± 2.7 | 21.86 | 7.9 |