. Author manuscript; available in PMC: 2023 Oct 1.

Published in final edited form as: Magn Reson Imaging. 2022 Jun 28;92:140–149. doi: 10.1016/j.mri.2022.06.016

Table 4.

Comparison between ventilation defect segmentation in participants with and without COPD using cascaded U-Net in the test set (n = 14).

	COPD	No COPD	P value
	n = 8)	(n = 6)
Non-ventilated (³He)
DSC	0.851 ± 0.056	0.826 ± 0.061	0.41
MSD (mm)	1.228 ± 1.630	1.338 ± 1.158	0.75
Hypo-ventilated (³He)
DSC	0.653 ± 0.208	0.799 ± 0.066	0.06
MSD (mm)	1.516 ± 1.561	0.700 ± 0.331	0.66
Normal ventilated (³He)
DSC	0.861 ± 0.071	0.912 ± 0.024	0.18
MSD (mm)	1.855 ± 1.158	1.042 ± 0.748	0.08

Note. —Data are presented as mean ± standard deviation. DSC = Dice similarity coefficient, MSD = mean surface distance. The Mann-Whitney U test was used to compare participants with and without COPD.