RT Journal Article SR Electronic T1 Alan Seymour Philps JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 318 OP 319 DO 10.1136/bjo.40.5.318 VO 40 IS 5 YR 1956 UL http://bjo.bmj.com/content/40/5/318.abstract AB