Noninvasive lung water quantitation by 1H nuclear magnetic resonance spectroscopy

Three models of volume-dependent pulmonary edema were used in rabbits. Changes in lung water were measured by proton (1H) nuclear magnetic resonance spectroscopy (NMR) using a surface coil system, topical magnetic resonance. The anesthetized rabbits were ventilated with high frequency jet ventilation to minimize lung motion, and the surface coil was placed on the rabbit chest wall over the right lung. The rabbit preparation was placed in an Oxford Research Systems TMR-32 20-cm bore magnet. There was a close correlation (r greater than or equal to 0.90) between the gravimetrically determined lung wet to dry weight ratios and the percent change in the spectral areas as measured with 1H NMR, in all 3 experimental models.