Laura Carrero-Gonzalez1,2, Thomas Kaulisch1,
Jesus Ruiz-Cabello2,3, Jose Manuel Perez-Sanchez4,
German Peces-Barba5, Detlef Stiller1, Ignacio Rodriguez2,3
1Boehringer Ingelheim
Pharma GmbH & Co. KG, Biberach an der Riss, Baden-Wrttemberg, Germany; 2Universidad
Complutense de Madrid, Madrid, Spain; 3CIBER de Enfermedades
Respiratorias, Madrid, Spain; 4Unit de Recherche en Rsonance
Magntique Mdicale (UMR 8081), Univ.Paris-Sud, CNRS, Orsay, France; 5Fundacin
Jimnez-Daz, Madrid, Spain
Apparent diffusion coefficient (ADC) of HP-gases is a parameter that reflects changes in lung microstructure but it depends on many physiological and experimental variables. The application of a positive end expiratory pressure (PEEP) causes an increase of the residual volume. If incoming and residual gases do not have similar diffusion coefficient, the obtained ADC values will be affected. A proposed single breath-hold protocol uses 4He-O2 for ventilation and HP3He-N2 for imaging. Both gas mixtures have a very similar diffusion coefficient. ADCs obtained from the proposed strategy show to be independent of PEEP, thus minimizing the effect of the different residual volumes.