An MR comparison study of cardiogenic and noncardiogenic pulmonary edema in animal models.

ABSTRACT

PURPOSE: To apply magnetic resonance (MR) imaging to differential diagnosis of cardiogenic pulmonary edema (CPE) and noncardiogenic pulmonary edema (NCPE). MATERIALS AND METHODS: In the CPE group, MR measurements were performed on 5 rats just before and 3 h after administration of 21 ± 2% body weight of normal saline. In the NCPE group, measurements were similarly performed on 5 animals just before and 48 h after 0.75 mg/body of lipopolysaccharide intratracheal administration. Animals were killed for bronchoalveolar lavage fluid (BALF) or pathological analysis after MR measurements. RESULTS: The relation between signal intensity and the T(2)* value of MR imaging was different in the two groups. The T(2)* in the NCPE group was significantly longer than that in the CPE group at the same signal intensity level. The lactate levels measured by in vivo MR spectroscopy did not show a difference between the CPE and NCPE groups, although the lactate BALF levels of the two groups were significantly different. CONCLUSION: The relation between signal intensity and T(2)* value was useful for the differentiation between these two pulmonary diseases. The measurable lactate level in pulmonary lesions suggests the applicability of MR spectroscopy to pulmonary disease.