Examining lung microstructure using F MR diffusion imaging in COPD patients.

Purpose: To examine the time-dependent diffusion of fluorinated ( F) gas in human lungs for determination of surface-to-volume ratio in comparison to results from hyperpolarized Xe and lung function testing in healthy volunteers and patients with chronic obstructive pulmonary disease.

Methods: Diffusion of fluorinated gas in the short-time regime was measured using multiple gradient-echo sequences with a single pair of trapezoidal gradient pulses. Pulmonary surface-to-volume ratio was calculated using a first-order approximation of the time-dependent diffusion in a study with 20 healthy volunteers and 22 patients with chronic obstructive pulmonary disease.

Effects of ultrafine particles on the allergic inflammation in the lung of asthmatics: results of a double-blinded randomized cross-over clinical pilot study.

Background: Epidemiological and experimental studies suggest that exposure to ultrafine particles (UFP) might aggravate the allergic inflammation of the lung in asthmatics.

Methods: We exposed 12 allergic asthmatics in two subgroups in a double-blinded randomized cross-over design, first to freshly generated ultrafine carbon particles (64 μg/m³; 6.1 ± 0.