Quantitative evaluation of pulmonary ventilation dynamics using MR imaging: comparison of smokers and non-smokers.

PURPOSE

This quantitative study was conducted to evaluate lobar ventilation dynamics in non-smokers and smokers using MR imaging.

METHODS

Ten non-smoker males and ten smoker males underwent MR imaging in the supine position without breath-holding. The volume rates and fluctuation rates were calculated for each lobe from MR images. TVRCs were constructed and analyzed.

RESULTS

In non-smokers, the mean volume rates for each lung and lobe arranged in order of diminishing values were RL (54.8%), LL (45.2%), RLL (25.9%), LUL (24.2%), LLL (21.0%), RUL (18.5%), and RML (10.3%). In smokers, the mean volume rates for each lung and lobe arranged in order of diminishing values were RL (55.7%), LL (44.3%), RLL (25.1%), LUL (24.0%), RUL (21.0%), LLL (19.9%), and RML (9.5%). In both groups, there was a tendency for the fluctuation rates of the lower lobes to be higher than those of the upper and middle lobes. Although TVRCs for the right and left lung were nearly parallel, with no time lag, the peaks of TVRCs for the upper and middle lobes appeared slightly earlier than those for the lower lobes.

CONCLUSION

The evaluation of pulmonary ventilation dynamics using MR may be a useful non-invasive technique by which to assess lung lobar ventilation.