Table 3. Correlation of CT-Quantitative EAtC Mapping and PRM Classes with PFTs, BODE Index, and SGRQ Score.
| Method | PFTs and Clinical Variables | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| FEV1 | FEV1/FVC | FEF25–75% | RV | TLC | RV/TLC | DLCO | BODE Index | SGRQ | ||
| EAtC | ||||||||||
| Normal | 0.559 | 0.674 | 0.500 | −0.475 | −0.471 | −0.452 | 0.361 | −0.561 | −0.349 | |
| fAT | −0.567 | −0.659 | −0.502 | 0.491 | 0.469 | 0.474 | −0.333 | 0.584 | 0.354 | |
| Emph | −0.430 | −0.605 | −0.423 | 0.327 | 0.384 | 0.280 | −0.516 | 0.425 | 0.256 | |
| PRM | ||||||||||
| PRMNormal | 0.547 | 0.661 | 0.463 | −0.454 | −0.454 | −0.426 | 0.349 | −0.533 | −0.324 | |
| PRMfSAD | −0.383 | −0.411 | −0.337 | 0.331 | 0.279 | 0.345 | −0.041* | 0.319 | 0.191 | |
| PRMEmph | −0.488 | −0.647 | −0.471 | 0.366 | 0.407 | 0.326 | −0.502 | 0.475 | 0.275 | |
Data are presented as correlation coefficients determined using the Pearson's correlation test for Normal, fAT, PRMNorm and PRMfSAD and Spearman's correlation for Emph and PRMEmph. *p values > 0.05. Otherwise, p values < 0.05. BODE = Body mass index, airflow Obstruction, Dyspnea and Exercise capacity, DLCO = carbon monoxide diffusing capacity corrected for hemoglobin concentration, EAtC = emphysema air-trapping composite, Emph = emphysema by EAtC, fAT = functional air trapping by EAtC, FEF25–75% = mean forced expiratory flow between 25% and 75% of FVC, FEV1 = forced expiratory volume in 1 second, FVC = forced vital capacity, Normal = normal lung parenchyma by EAtC, PFT = pulmonary function test, PRM = parametric response mapping, PRMEmph = emphysema by PRM, PRMfSAD = functional small airways disease by PRM, PRMNormal = normal lung by PRM, RV = residual volume, SGRQ = St. George's Respiratory Questionnaire, TLC = total lung capacity