A Simple Sign for Recognizing Off-Axis OCT Measurement Beam Placement in the Context of Multicentre Studies. Balk LJ, de Vries-Knoppert WAEJ, Petzold A PLoS One. 2012; 7(11):e48222. Epub 2012 Nov 08. PMID: 23144857. Abstract CommentRecommendBookmarkWatch