Table 5.

Pearson correlation coefficients between DL_CO/V_A%P results and CT-derived indices for each lobe

	RUL		RML		RLL		LUL		LLL
	r	P-value	r	P-value	r	P-value	r	P-valxe	r	P-value
TLVI (L)	−0.29	0.138	−0.12	0.539	0.00	1.000	−0.28	0.152	−0.35	0.070
TLVE (L)	−0.31	0.106	−0.17	0.399	−0.02	0.908	−0.29	0.136	−0.32	0.092
ELVI (%)	−0.68	0.000	−0.44	0.019	−0.44	0.019	−0.63	0.000	−0.47	0.012
ELVE (%)	−0.56	0.002	−0.51	0.005	−0.52	0.004	−0.59	0.001	−0.45	0.016
NLVI (L)	0.25	0.193	0.05	0.813	0.29	0.135	0.28	0.144	0.03	0.897
NLVE (L)	−0.10	0.620	−0.05	0.803	0.08	0.674	−0.07	0.724	−0.15	0.453
ΔTLV* (L)	0.00	0.992	0.02	0.930	0.03	0.894	0.02	0.915	−0.19	0.343
TLVCR** (%)	0.19	0.321	0.07	0.740	0.05	0.794	0.09	0.639	0.03	0.893
ΔNLV† (L)	0.56	0.002	0.31	0.111	0.28	0.154	0.50	0.006	0.19	0.344
NLVCR‡ (%)	0.59	0.001	0.31	0.111	0.21	0.281	0.52	0.004	0.22	0.256

Notes:

^*ΔTLV = TLV_I − TLV_E

^**TLV_CR = (1 − TLV_E/TLV_I) × 100

^†ΔNLV = NLV_I − NLV_E

^‡NLV_CR = (1 − NLV_E/NLV_I) × 100.

Abbreviations: CR, collapsibility ratio; CT, computed tomography; DL_CO/V_A%P, ratio of the diffusion capacity for carbon monoxide to alveolar gas volume, measured as percent predicted; E, expiratory; ELV, emphysematous lobar volume; I, inspiratory; LLL, left lower lobe; LUL, left upper lobe; NLV, normal lobar volume; r, Pearson correlation coefficient; RLL, right lower lobe; RML, right middle lobe; RUL, right upper lobe; TLV, total lobar volume.