[1] Childrens Hosp, Div Neurol, Philadelphia, PA 19104 USA
[2] Childrens Hosp, Neuroophthalmol Serv, Philadelphia, PA 19104 USA
[3] Childrens Hosp, Div Ophthalmol, Philadelphia, PA 19104 USA
[4] Childrens Hosp, Div Radiol, Philadelphia, PA 19104 USA
[5] Univ Penn, Perelman Sch Med, Dept Neurol, Philadelphia, PA 19104 USA
[6] Univ Penn, Perelman Sch Med, Dept Pediat, Philadelphia, PA 19104 USA
[7] Univ Penn, Perelman Sch Med, Dept Ophthalmol, Philadelphia, PA 19104 USA