The feasibility of CT lung volume as a surrogate marker of donor-recipient size matching in lung transplantation

Donor-recipient size matching in lung transplantation (LTx) by computed tomography lung volume (CTvol) may be a reasonable approach because size matching is an anatomical issue. The purpose of this study is to evaluate the feasibility of CTvol as a surrogate marker of size matching in LTx by comparing CTvol and predicted total lung capacity (pTLC) to reference total lung capacity (TLC) values. From January to December 2014, data from 400 patients who underwent plethysmography, pulmonary function testing (PFT), and chest computed tomography scans were reviewed retrospectively. Enrolled 264 patients were divided into 3 groups according to PFT results: Group I, obstructive pattern; Group II, restrictive pattern; Group III, normal range. The correlations between pTLC and TLC and between CTvol and TLC were analyzed, and the linear correlation coefficients were compared. The percentage error rates of pTLC and CTvol were calculated and absolute error rates were compared. The correlation coefficient between CTvol and TLC in Group I was larger than that of pTLC and TLC (0.701 vs 0.432, P = 0.002). The absolute percentage error rate between CTvol and pTLC was lower than that of pTLC in Group II (15.3% +/- 11.9% vs 42.2% +/- 28.1%, P < 0.001). CTvol showed similar or better correlation with TLC compared to the pTLC in normal participants and patients with obstructive or restrictive pulmonary diseases. CTvol showed a smaller error rate in patients with restrictive disease. The results suggest that CTvol may be a feasible method for size matching in LTx.