WHO Definitions of Low Vision

What is WHO's definition of low vision? - Zoomax

What is WHO's definition of low vision?


In the practice of eye care "LOW VISION" has a specific meaning as defined by WHO.


"A person with low vision is one who has impairment of visual functioning even after treatment and/or standard refractive correction, and has a visual acuity of less than 6/18 to light perception, or a visual field of less than 10 degree from the point of fixation, but who uses, or is potentially able to use, vision for planning and/or execution of a task. "


Under this definition persons who would benefit from low vision care also exist among those who are currently categorized as blind.


The term "low vision" included in the previous revision has been replaced by categories 1 and 2.


Presenting distance visual acuity
CategoryWorse than:Equal to or better than:

Mild or no visual

impairment

0


6/18

3/10 (0.3)

20/70

Moderate visual

impairment

1

6/18

3/10 (0.3)

20/70

6/60

1/10 (0.1)

20/200

Severe visual impairment

2

6/60

1/10 (0.1)

20/200

3/60

1/20 (0.05)

20/400

Blindness

3

3/60

1/20 (0.05)

20/400

1/60*

1/50 (0.02)

5/300 (20/1200)

Blindness

4

1/60*

1/50 (0.02)

5/300 (20/1200)

Light perception

Blindness

5

No light perception
9Undetermined or unspecified 


* Or counts fingers (CF) at 1 metre.


Values are Snellen meters (Snellen feet) and [LogMAR]. CF, count fingers.



Any help or request about low vision and visual impairment, please contact Zoomax. We are here for you.

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