Value of Post contrast FLAIR in the Diagnosis of Cerebral Metastases in Cancer Patients

Metastases to the brain, epidural space and meninges constitute the major cause of neurological dysfunction in cancer patients. MRI, FLAIR imaging is a useful non invasive screening modality for brain metastases. Post contrast FLAIR imaging effectively depicts parenchymal and leptomeningeal metastases.The Objectives of this Study: To evaluate the usefulness of pre- and post contrast FLAIR images in the detection of intracranial lesions which may be encountered in cancer patients, compared to conventional T l , T2W as well as post contrast T1W images.Patients and Methods: Seventy patients with known malignancy and suspected cranial metastases underwent FLAIR and spin echo T1W before and after contrast as well as T2W images. Images were compared for lesion conspicuity and enhancement, number of parenchymal metastases andextension of leptomeningeal cisternal metastases.Results: Parenchymal metastases were demonstrated in 59 patients. Compared with Tl W images, post contrast FLAIR images showed 10 metastases more in 5 patients, an equal number (45 lesions in 20 patients) and fewer numbers of 8 lesions in 5 patients. Regarding lesion conspicuity, postcontrast FLAIR images were superior in 5, equal in 16 and inferior in 9. Superior FLAIR results for lesion number, conspicuity and enhancement were observed in the same 5 patients.Conclusion: Postcontrast FLAIR is a useful adjunct to post contrast T1W imaging and the routine use of FLAIR imaging before and after the administration of contrast material is particularly useful for delineating leptomeningeal cisternal and cranial nerve metastases.