[1] Boston Childrens Hosp, Div Resp Dis, Boston, MA USA
[2] Ann & Robert H Lurie Childrens Hosp, Div Pulm Med, Dept Pediat, Chicago, IL USA
[3] Harvard Med Sch, Div Pulm & Crit Care Med, Dept Med, Mt Auburn Hosp, Boston, MA USA
[4] Univ Wisconsin, Sch Med & Publ Hlth, Dept Pediat, Div Pediat Pulmonol & Sleep Med, Madison, WI USA
[5] Childrens Hosp Philadelphia, Div Pulm Med & Cyst Fibrosis Ctr, Philadelphia, PA 19104 USA
[6] Univ Penn, Div Pulm Med, Dept Pediat, Childrens Hosp Philadelphia,Perelman Sch Med, Philadelphia, PA 19104 USA
[7] Ann & Robert H Lurie Childrens Hosp, Dept Med Imaging, Chicago, IL USA
[8] Northwestern Univ, Feinberg Sch Med, Chicago, IL USA
[9] Med Univ South Carolina, Dept Radiol & Radiol Sci, Charleston, SC 29425 USA
[10] Med Univ South Carolina, Dept Pediat, Charleston, SC 29425 USA
[11] Washington Univ, Dept Pediat, St Louis, MO USA
[12] Washington Univ, Sch Med, St Louis, MO USA
[13] Harvard Med Sch, Div Thorac Surg & Intervent Pulmonol, Beth Israel Deaconess Med Ctr, Boston, MA USA
[14] Vanderbilt Univ, Sch Med, Dept Pediat, Nashville, TN 37235 USA