FLAIR MR imaging for diagnosing intracranial meningeal carcinomatosis.

OBJECTIVE: The purpose of this study was to compare unenhanced and contrast-enhanced fluid-attenuated inversion recovery (FLAIR) imaging with other sequences to visualize meningeal carcinomatosis.

MATERIALS AND METHODS: Unenhanced FLAIR images were compared with spin echo T2-weighted and contrast-enhanced FLAIR images in five patients with documented meningeal carcinomatosis and four patients with suspected meningeal carcinomatosis. Comparisons were also made between contrast-enhanced T1-weighted and FLAIR images.

RESULTS: In six patients, the unenhanced FLAIR images showed areas of abnormal hyperintensity within the sulci that were not noted on the spin-echo T2-weighted images. In all patients, the contrast-enhanced FLAIR images also showed meningeal enhancement, periventricular enhancement, or both. The contrast-enhanced T1-weighted and FLAIR images were equivalent in their depiction of abnormal enhancement in five of the nine patients; contrast-enhanced FLAIR images were superior in three patients.

CONCLUSION: Unenhanced FLAIR images are of more value than spin-echo T2-weighted images for the diagnosis of intracranial meningeal carcinomatosis. Contrast-enhanced FLAIR images can sometimes surpass contrast-enhanced T1-weighted images in their quality.