@article {PennatiOA2949, author = {Francesca Pennati and Caterina Salito and David Roach and John P. Clancy and Jason Woods and Andrea Aliverti}, title = {Regional ventilation in infants quantified by multi-volume high resolution computed tomography (HRCT) and multi-volume proton magnetic resonance imaging (MRI)}, volume = {46}, number = {suppl 59}, elocation-id = {OA2949}, year = {2015}, doi = {10.1183/13993003.congress-2015.OA2949}, publisher = {European Respiratory Society}, abstract = {Previous studies demonstrated that regional intensity variations between different lung volumes acquired by HRCT (Aliverti et al,ERJ2013) and by proton-MRI (Pennati et al,Radiology2014) can be used as estimates of regional ventilation.The aim of the study is to compare maps of CT-density difference (ΔHU) with the corresponding maps of proton-signal-density difference in pediatric patients.Seven infants (age 6-24mo) with cystic fibrosis (CF) were scanned during breath-hold at functional residual capacity (FRC)and total lung capacity (TLC) through HRCT and MRI. FRC was registered onto TLC by the Demons algorithm and maps of ΔHU and of proton-density difference were obtained by voxel-by-voxel subtraction between the two lung volumes.Difference maps were compared by computing the linear correlation between the median values of ΔHU and of proton-density difference in six corresponding regions at five equally-spaced lung levels.Fig. 1 shows matched HRCT and MRI slices at TLC and FRC,with the corresponding difference maps in a representative infant.In the overall population the average{\textpm}SD correlation coefficient is R2=0.6{\textpm}0.2.Multi-volume HRCT and MRI demonstrate good correlation in CF infants, with significant regional variation,suggesting that proton-density difference may be used to describe ventilation patterns in infants with CF, with no radiation dose.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/46/suppl_59/OA2949}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }