RT Journal Article SR Electronic T1 QCT analysis of emphysema and air trapping in coil-based lung volume reduction treatment JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP OA1769 DO 10.1183/13993003.congress-2015.OA1769 VO 46 IS suppl 59 A1 K. Kontogianni A1 Y. Yin A1 M. Schuhmann A1 P. Raffy A1 R. Eberhardt A1 D. Gompelmann A1 F. Herth YR 2015 UL http://erj.ersjournals.com/content/46/suppl_59/OA1769.abstract AB Background: Degree of emphysema is believed to be associated with response to coil-based lung volume reduction (LVR) treatment. However, little is known about the impact of air trapping (AT).Objectives: To assess association of AT with reduction in residual volume (RV)Methods: 42 severe emphysema patients were treated with PneumRx coils. ΔRV%≤-10% defined positive response(18 responders). Registration-based disease probability measures (DPMs) of emphysema (DPM_EMPH) and air trapping only (DPM_AT) have shown to better discriminate these subtypes of COPD when compared to threshold-based, single scan measures of emphysema (LAA-950) and AT (LAA-856). DPM and LAA measures were computed for treated lobe using Apollo (VIDA Diagnostics, IA).Results: DPM measures yield higher correlations (r/p-value) against ΔRV% than LAA measures: DPM_EMPH(-0.31/0.046) vs. LAA-950(-0.29/0.062), DPM_AT(0.35/0.024) vs. LAA-856(-0.11/0.50). DPM_EMPH (p=0.03) is a significant predictor of ΔRV% with higher value for responders. Non-responders tend to have more DPM_AT(p=0.06) than responders. LAAs are not predictive. Figure shows DPM maps in two subjects with LUL treatment. Responder is associated with greater emphysema and limited to low AT-only tissue.Conclusions: Registration-based DPM measures are able to separate AT-only and emphysema subtypes. QCT has promise for greater prediction of response for patients undergoing coil-based LVR therapy.