Visual Impairment Categories
Visual Impairment Categories
The classification of blindness and low vision changes according to the criteria adopted by different countries. In Sweden, the Czech Republic, Cyprus and Poland, as in most European countries, reference is made to the World Health Organization (WHO) guidelines.
WHO classification — visual acuity and visual field
| Category | Visual acuity (with best correction) | Visual field |
|---|---|---|
| Moderate low vision | > 2/20 and < 7/20 | > 20° |
| Severe low vision | < 2/20 or equal to 1/20 | > 10° but < 20° |
| Blindness | < 1/20 | < 10° |
| Deep blindness | No light perception — no movement perception | Not evaluable |
| Category | Definition |
|---|---|
| Totally blind | Total lack of vision in both eyes; or only perception of shadows and light or hand motion (moto manu); or binocular perimeter residue less than 3%. |
| Partly blind | Visual residue not exceeding 1/20 in both eyes or in the better eye, with the best correction; or binocular perimeter residue less than 10%. |
| Severely visually impaired | Residual vision not exceeding 1/10 in both eyes or in the better eye, even with the best possible correction; or residual binocular perimeter less than 30%. |
| Medium-severe visually impaired | Residual vision not exceeding 2/10 in both eyes or in the better eye, even with the best possible correction; or residual binocular perimeter less than 50%. |
| Mildly visually impaired | Residual vision not exceeding 3/10 in both eyes or in the better eye, even with possible correction; or residual binocular perimeter less than 60%. |
The classification of blindness and low vision changes according to the criteria adopted by different countries. In Sweden, the Czech Republic, Cyprus and Poland, as in most European countries, reference is made to the World Health Organization (WHO) guidelines.