4.76a—Computation of average concentric contraction of visual fields.
| Meridian | Normal degrees |
|---|---|
| Temporally | 85 |
| Down temporally | 85 |
| Down | 65 |
| Down nasally | 50 |
| Nasally | 60 |
| Up nasally | 55 |
| Up | 45 |
| Up temporally | 55 |
| Total | 500 |
Code of Federal Regulations
Code of Federal Regulations
407
Example of computation of concentric contraction under the schedule with abnormal findings taken from Figure 1.
| Loss | Degrees |
|---|---|
| Temporally | 55 |
| Down temporally | 55 |
| Down | 45 |
| Down nasally | 30 |
|
Code of Federal Regulations
408
|
|
| Nasally | 40 |
| Up nasally | 35 |
| Up | 25 |
| Up temporally | 35 |
| Total loss | 320 |
| Remaining field 500° minus 320° = 180°. 180° ÷ 8 = 221/2° average concentric contraction. | |