Abstract #1664

Mugler J, Altes T, Juersivich A, Battiston J, Platts-Mills T, de Lange E

37 asthmatics underwent hyperpolarized helium-3 MR twice: 20 on the same day and 17 on two different days, mean time between scans 4.3 min and 78 days respectively. The percent of the ventilation defects present on the first scan that were present in the same location on the second scan was 86%(23%) for the subjects scanned on the same day and 67%(25%) for subjects scanned on two different days. The surprisingly large number of ventilation defects that persisted or recurred in the same location on scans widely separated in time suggests that asthma is a regional disease.