Diagnostic value of contrast-enhanced fluidattenuated inversion recovery MR imaging of intracranial metastases
Abstract. Postcontrast fluid-attenuated inversion recovery (FLAIR) imaging effectively depicts parenchymal and leptomeningeal metastases, as reported. We compared postcontrast T1-weighted (T1W) and FLAIR imaging in a group of 50 patients, and to compare our results with published ones regarding the so-called effect of “late enhancement” as well. Fifty patients with known malignancy and suspected cranial metastases underwent axial FLAIR and spin-echo T1W imaging without and with intravenous gadopentetate dimeglumine (GD). Postcontrast images were compared for lesion conspicuity and enhancement, number of parenchymal metastases, and extension of leptomeningeal-cisternal metastases. All postcontrast FLAIR sequences were obtained after the postcontrast T1W sequences. Parenchymal metastases were demonstrated in 30 patients.Regarding all established criteria postcontrast FLAIR imaging was superior in two patients, equal in five, and inferior in 23. FLAIR imaging was performed as the second postcontrast sequence. Five patients had leptomeningeal-cisternal metastases; lesion conspicuity, extension, and enhancement were superior on postcontrast FLAIR images in all five patients. FLAIR imaging was performed as the second postcontrast sequence. Nine patients had cranial-nerve metastases; in eight, postcontrast FLAIR imaging was superior for lesion conspicuity and extension. In all patients, FLAIR imaging was the second postcontrast sequence. Postcontrast FLAIR imaging is a valuable adjunct to postcontrast T1W imaging. Precontrast and postcontrast FLAIR imaging effectively delineates parenchymal metastases, particularly leptomeningeal-cisternal and cranial-nerve metastases.
Key words: POSTCONTRAST FLAIR. INTRACRANIAL METASTASE