Magnetic resonance imaging of the chest: a diagnostic comparison with computed tomography and hilar tomography.

Computed tomography (with and without contrast enhancement) provides excellent diagnostic accuracy for the evaluation of the chest. Oblique (55 degrees) and anteroposterior hilar tomography is accurate for the evaluation of hilar nodes and masses. Magnetic resonance techniques provide excellent differentiation of vascular and nonvascular structures and therefore should be useful in the hilum and mediastinum. Magnetic resonance imaging was used in 55 patients with known pathologic conditions in the mediastinum, hilum, and lungs to determine the accuracy and efficacy of this technique compared with computed and hilar tomography. The pathologic conditions included primary and metastatic neoplasms, benign masses, vascular abnormalities, and pulmonary nodules and infiltrates. Spatial resolution with magnetic resonance imaging is less than with computed tomography with our instrument (0.15 T resistive magnet). However, in the hilum and mediastinum, magnetic resonance imaging provided diagnostic information equal to that of computed tomography with contrast in 90% of patients. Vascular and nonvascular structures were more easily differentiated than with hilar tomography. Computed tomography was far superior in the evaluation of multiple pulmonary nodules. Lesions of the chest wall were better seen with magnetic resonance imaging because of the improved soft tissue contrast.