Young Investigator Award Presentation at the 13th Annual Meeting of the ESMRMB, September 1996, Prague Quantification of pulmonary water compartments by magnetic resonance

Abstract

The purpose of this study was to quantify pulmonary water compartments of total, intravascular, and extravascular lung water in excised and perfused sheep lungs with the use of magnetic resonance imaging techniques. Total lung water was measured by proton density maps calculated from multi-spin-echo images. Intravascular lung water was evaluated by magnetic resonance angiography before and after injection of gadolinium diethylenetriamine penta-acetic acid polylysine, a macromolecular paramagnetic contrast agent. Intravascular lung water was calculated from signal intensity histogram changes comparing pre- and postcontrast angiograms. Extravascular water was calculated as the difference between total and intravascular lung water. Quantities of total and intravascular lung water measured by magnetic resonance techniques were compared to reference results obtained from wet/dry weight gravimetry and Evans blue dilution performed after imaging. Magnetic resonance and reference results correlated significantly (total lung water: r = 0.93, p < 0.001; intravascular lung water: r = 0.80, p < 0.001; extravascular lung water: r = 0.89, p < 0.001). Therefore, we conclude that quantitative magnetic resonance techniques are potentially useful for the clinical evaluation of pulmonary water compartments.

Blood volume fraction imaging of the human lung using intravoxel incoherent motion

“…The values of f observed within the lung parenchyma with the presented technique in all subjects (MV ± STD = 36 ± 16%) are in good agreement with the result obtained in a previous report using contrast‐enhanced MR angiography (MV = 33%) . The large standard deviation obtained can be associated with the heterogeneity observed in the maps between the inner part of the lung, with higher f , and the periphery, with lower f .…”

“…Another interesting perfusion parameter of the lung is the blood volume fraction . This parameter can be easily defined using a two‐compartment model of the lung, where the total lung water (TLW) is divided up into the intravascular lung water (IVLW) and the extravascular lung water (EVLW).…”

“…Quantification of the blood volume fraction using contrast‐enhanced MRI has been proposed in the past. This was achieved by performing either MR angiography or T 1 mapping , before and after the administration of contrast agent. However, clinical applications of these techniques to the human lung can be rarely found in the literature.…”