RT Journal Article SR Electronic T1 The definition and classification of glaucoma in prevalence surveys JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 238 OP 242 DO 10.1136/bjo.86.2.238 VO 86 IS 2 A1 Paul J Foster A1 Ralf Buhrmann A1 Harry A Quigley A1 Gordon J Johnson YR 2002 UL http://bjo.bmj.com/content/86/2/238.abstract AB This review describes a scheme for diagnosis of glaucoma in population based prevalence surveys. Cases are diagnosed on the grounds of both structural and functional evidence of glaucomatous optic neuropathy. The scheme also makes provision for diagnosing glaucoma in eyes with severe visual loss where formal field testing is impractical, and for blind eyes in which the optic disc cannot be seen because of media opacities.