@article {BordasP541, author = {Rafel Bordas and Sherif Gonem and Christophe Lefevre and Bart Veeckmans and Ruth Hartley and Joe Pitt-Francis and Catalin Fetita and Chris Brightling and John Owers-Bradley and David Kay and Salman Siddiqui and Kelly Burrowes}, title = {Clinical validation of a CT-based impulse oscillometry model}, volume = {44}, number = {Suppl 58}, elocation-id = {P541}, year = {2014}, publisher = {European Respiratory Society}, abstract = {Rationale: Impulse oscillometry (IOS) is a common clinical technique to probe airway structure. The IOS parameter R5-R20 is believed to be a measure of heterogeneous small airways obstruction and is related to asthma exacerbation frequency (Gonem et al. ERJ 2012, Gonem et al. CEA 2013). We utilised patient specific computational airway models (Fig.1a) to simulate IOS airway resistance parameters and correlated them with measured data.Methods: Clinical demographic and IOS data were collected for 33 subjects (15M/18F, 55{\textpm}30 yo). The subjects belonged to 3 subgroups (healthy, asthmatic with frequency dependence (FD), asthmatic without FD). Patient specific airway models were created by first segmenting the lobes and major airways from CT data. A volume filling branching algorithm was applied to extrapolate the remaining airway tree (Fig 1a). An acoustic impedance model was used to simulate IOS parameters for each airway tree.Results: Simulated resistance measures demonstrated statistically significant moderate correlations with IOS measurements (R5-R20: r=0.57, p \< 0.001, R5: r=0.52, p \< 0.002, Fig. 1b).Conclusions: Resistance measures simulated using the model correlate with their clinical counterparts. This opens up the possibility of investigating the link between airway structure and clinical IOS resistance recordings on a patient specific basis.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/44/Suppl_58/P541}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }