Increased detection of intracranial metastases using intravenous Gd-DTPA

Three patients with intracranial metastases were studies with MR imaging before and after intravenous administration of Gd-DTPA. Pre- and post-contrast-enhanced images showed a total of six and 41 metastases, respectively. Of the 35 lesions detected only after contrast agent enhancement, all were less than 10 mm in size, and none had evidence of surrounding edema. Lesion conspicuity was comparable on postcontrast mixed (T1, proton density, and T2) and T1-weighted images, suggesting the feasibility of effectively screening for metastases with a single postcontrast spin-echo sequence providing mixed and T2-weighted images. There were no side effects or complications. The diagnostic, therapeutic, and economic implications of these findings are discussed