Contrast agents in MRI: clinical experience

The author's clinical experience shows that contrast enhancement significantly improves the diagnostic utility of MRI in the setting of intracranial neoplastic disease. The application of Gd DTPA permits the differentiation of neoplastic tissue (corresponding to a lesion of the blood-brain barrier) from surrounding cerebral edema. The use of such contrast media furthermore improves the sensitivity to disease. Enhancement on MRI proved to be superior to that on X-ray CT in all cases. The pattern of enhancement may lend further diagnostic specificity, as it has in CT. However with MRI one has two parameters, T1 and T2, compared to the single variable of X-ray attenuation with CT. Observation of the change in either of these relaxation parameters may add, with continued clinical experience, further tissue specificity. (Auth.)