RT Journal Article SR Electronic T1 Ultrasonography in Ophthalmology JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 637 OP 637 DO 10.1136/bjo.54.9.637-a VO 54 IS 9 YR 1970 UL http://bjo.bmj.com/content/54/9/637.2.abstract AB