Is there a special deduction for visual impairment?

Yes. If you are blind in at least one eye (you cannot see better than 20/200 in your better eye without lenses or your field of vision is 20 degrees or less), you can take an additional standard deduction amount. For 2012, this is $1,450 if you are single or $1,150 if you are a joint filer. You cannot get this break if you itemize personal deductions.