Spearman´s correlation coefficients (r) of the threshold-based method in expiration for varying threshold ranges.

<p>The percentage of voxels between -790 HU to -950 HU showed the best correlation with RV/TLC (r = 0.52, p<0.001). However, varying the lower threshold between (-950 to -1010 HU) and the upper threshold between (-770 HU to -810 HU) revealed no significant correlation improvement (P>0.05).</p><p>Spearman´s correlation coefficients (r) of the threshold-based method in expiration for varying threshold ranges.</p

Spearman rank correlation´s coefficients between the quantitative CT AT measures and RV/TLC.

<p>Spearman rank correlation´s coefficients between the quantitative CT AT measures and RV/TLC.</p

Patient characteristics.

<p>Patient characteristics.</p

Flowchart of patients included in the study.

<p>LTx  =  lung transplantation, DLTx  =  double lung transplantation, BOS  =  bronchiolitis obliterans syndrome, m  =  male, f  = female, y  =  years; median and 25; 75 interquartile range for age distribution.</p

Bland-Altman plots of RV/TLC against the three evaluated CT measures for quantification of AT%.

<p>In comparison to RV / TLC, EXP_{-790 to -950 HU} (A) showed the smallest mean difference (bias) of -3.08% but the highest range in the 95% limits of agreement (-34.7% to 28.5%). E/I-ratio MLD and DM (B, C) showed smaller ranges of the 95% limits of agreement (-58.9% to -28.5% and -9.8% to 34.8%, respectively) suggesting a higher agreement with RV / TLC. Bias was highest with E/I-ratio MLD (-43.7%) while DM showed a moderate bias of 12.5%.</p

Spearman´s correlation coefficients (r) of detected AT in the DM with RV/TLC for varying attenuation ranges and varying HU-differences between registered inspiration and expiration.

<p>DM was robust regarding the attenuation ranges of the upper threshold and the HU-differences showing similar correlation of DM with RV/TLC for all parameter settings (0.62 ≤ r ≤ 0.66).</p><p>Spearman´s correlation coefficients (r) of detected AT in the DM with RV/TLC for varying attenuation ranges and varying HU-differences between registered inspiration and expiration.</p

ROC curves of three quantitative CT measures to detect pAT in patients after lung transplantation.

<p>Measurements were corrected for bias. Density mapping showed the largest AUC under the ROC curve of 0.78.</p

Reiff score.

<p>Reiff score.</p

Patient characteristics.

<p>Patient characteristics.</p

Collateral findings.

<p>Collateral findings.</p