1 Department of Ophthalmology and Vision Sciences (Kwok, Christakis), University of Toronto, Toronto, Ont.; School of Medicine (Yu), Queen's University, Kingston, Ont.; Department of Ophthalmology (Christakis), Toronto Western Hospital, Toronto, Ont.
2 Department of Ophthalmology and Vision Sciences (Kwok, Christakis), University of Toronto, Toronto, Ont.; School of Medicine (Yu), Queen's University, Kingston, Ont.; Department of Ophthalmology (Christakis), Toronto Western Hospital, Toronto, Ont. Panos.Christakis@uhn.ca.