Evaluation of chest motion and volumetry during the breathing cycle by dynamic MRI in healthy subjects: comparison with pulmonary function tests

Abstract

Rationale and objectives: To investigate diaphragm and chest wall motion during the whole breathing cycle using magnetic resonance imaging (MRI) and a volumetric model in correlation with spirometry.

Materials and methods: Breathing cycles of 15 healthy volunteers were examined using a trueFISP sequence (5 slices in 3 planes, 3 images per second). Time-distance curves were calculated and correlated to spirometry. A model for vital capacity (VC), continuous time-dependent vital capacity (tVC), and investigating the influence of horizontal and vertical parameters on tVC was introduced.

Results: Time-distance curves of the breathing cycle using MRI correlated highly significant with spirometry (P < 0.0001). VC calculated by the model was similar to VC measured in spirometry (5.00 L vs. 5.15 L). tVC correlated highly significantly with spirometry (P < 0.0001). Vertical parameters had a more profound influence on tVC change than horizontal parameters.

Conclusions: Dynamic MRI is a simple noninvasive method to evaluate local chest wall motion and respiratory mechanics. It widens the repertoire of tools for lung examination with a high temporal resolution.