Vision impairment including blindness
Definition
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The table below gives a classification of severity of vision impairment based on visual acuity.
For epidemiological studies, it is recommended to collect the following information on visual acuity for each eye, for both eyes open and for distance and near.
a. Uncorrected visual acuity (9D96)
b. Presenting visual acuity (9D94)
c. Best corrected visual acuity (9D95)
Blindness is also categorized according to the degree of constriction of the central visual field in the better eye to less than 10 degrees.
| Category | Visual acuity *1
Worse than: |
Equal to or better than: |
|----------|--------------------------------|---------------------------------------------|
| No vision impairment | | 6/12
5/10 (0.5)
20/40
0.3 |
| 1 Mild vision impairment | 6/12
5/10 (0.5)
20/40
0.3 | 6/18
3/10 (0.3)
20/70
0.5 |
| 2 Moderate vision impairment | 6/18
3/10 (0.3)
20/70
0.5 | 6/60
1/10 (0.1)
20/200
1.0 |
| 3 Severe vision impairment | 6/60
1/10 (0.1)
20/200
1.0 | 3/60
1/20 (0.05)
20/400
1.3 |
| 4 Blindness | 3/60
1/20 (0.05)
20/400
1.3 | 1/60 or counts fingers (CF) at 1 metre
1/50 (0.02)
20/1200 or counts fingers (CF) at 1 metre
1.8 |
| 5 Blindness | 1/60
1/50 (0.02)
5/300 (20/1200)
1.8 | Light perception |
| 6 Blindness | No light perception | |
| 9 | Undetermined or unspecified | |
| Near vision impairment | N6 or M 0.8 at 40cms | |
*1 Presented in metres, decimals, feet and logMar
Coding note
For capturing and coding of “No vision impairment”, use QA00.62 (QA00.6 Examination of eyes or vision).
5 subordinate codes
Also indexed as
Nearby in Vision impairment
9D92Specific vision dysfunctions9D93Complex vision-related dysfunctions9D94Impairment of presenting visual acuity9D95Impairment of best corrected visual acuity9D96Impairment of uncorrected visual acuity4B4YOther specified diseases of the immune system4B4ZDiseases of the immune system, unspecified