Table 3.
Univariate analysis of DTI of the optic tracts and radiations on visual acuity.
| DTI measure | Normal visual acuity (n = 24) | Abnormal visual acuity (n = 26) | P value |
|---|---|---|---|
| Optic Tracts | |||
| Fiber trajectories | 10.229 | 9.000 | .63 |
| Tract volume (mm3) | 380.125 | 393.500 | .78 |
| Fiber trajectories/mm3 | 0.369 | 0.379 | .86 |
| Fractional anisotropy | 0.432 | 0.432 | .99 |
| Radial diffusivity (mm2/s) | 0.000881 | 0.000853 | .37 |
| Mean diffusivity (mm2/s) | 0.00118 | 0.00114 | .24 |
| λ1 (mm2/s) | 0.00178 | 0.00172 | .23 |
| λ2 (mm2/s) | 0.00100 | 0.000962 | .24 |
| λ3 (mm2/s) | 0.000756 | 0.000743 | .67 |
| Optic radiations | |||
| Fiber trajectories | 311.208 | 301.942 | .87 |
| Tract volume (mm3) | 5731.583 | 5582.885 | .78 |
| Fiber trajectories/mm3 | 1.326 | 1.238 | .50 |
| Fractional anisotropy | 0.523 | 0.482 | < .01 |
| Radial diffusivity (mm2/s) | 0.000631 | 0.000691 | < .01 |
| Mean diffusivity (mm2/s) | 0.000932 | 0.000975 | .02 |
| λ1 (mm2/s) | 0.00153 | 0.00153 | .81 |
| λ2 (mm2/s) | 0.000747 | 0.000805 | .01 |
| λ3 (mm2/s) | 0.000516 | 0.000577 | < .01 |