TABLE 2

Distribution Volume, FRC, and Heterogeneity Index

Distribution volumeR2 *
GroupSPECT (n = 4)PET (n = 4)FRC (n = 2)SPECT (n = 4)PET (n = 4)
Healthy-lung control1,023 ± 126989 ± 251713 ± 1000.72 ± 0.140.72 ± 0.1
Lobar obstruction919 ± 84771 ± 1010.75 ± 0.070.67 ± 0.03
Diffuse obstruction1,064 ± 70880 ± 96 †676 ± 970.8 ± 0.010.56 ± 0.19

  • ↵* Significant difference between SPECT and PET (P < 0.05).

  • ↵† Significant difference between SPECT and PET (P < 0.05).

  • R2 = coefficient of determination (heterogeneity index).

  • Data are expressed as mean ± SD.