[1] Liverpool Heart & Chest Hosp NHS Trust, Adult CF Unit, Liverpool, Merseyside, England
[2] Univ Liverpool, Inst Translat Med, Liverpool, Merseyside, England
[3] Alder Hey Childrens Hosp, Inst Pk, Liverpool, Merseyside, England
[4] Univ Liverpool, Inst Infect & Global Hlth, Liverpool, Merseyside, England
[5] Liverpool Heart & Chest Hosp NHS Trust, Dept Radiol, Liverpool, Merseyside, England
[6] Univ Washington, Dept Bioengn, Seattle, WA 98195 USA
[7] Liverpool Heart & Chest Hosp NHS Trust, Res Dept, Liverpool, Merseyside, England