Hi, I work with people who are blind or partially sighted and have recently heard two references to an individuals level of eyesight as being - 10 (minus 10)
I am guessing this is with reference to a prescription and would appreciate it if you would be able to clarify its meaning.
Video and written answer:
Qualified Optometrist Seamus Breslin BSc (Hons) MCOptom answers this question
It sounds like the glasses prescription...
For an explanation of a prescription, see our video below: