RT Journal Article SR Electronic T1 Corrigendum JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 864 OP 864 DO 10.1136/bjo.55.12.864-a VO 55 IS 12 YR 1971 UL http://bjo.bmj.com/content/55/12/864.2.abstract AB