[1] Univ So Calif, Dept Ophthalmol, Doheny Eye Inst, Los Angeles, CA 90033 USA
[2] Univ So Calif, Dept Ophthalmol, Keck Sch Med, Los Angeles, CA 90033 USA
[3] Univ So Calif, Keck Sch Med, Dept Prevent Med, Los Angeles, CA 90033 USA
[4] Childrens Hosp Los Angeles, Vis Ctr, Los Angeles, CA 90027 USA