Diagnostic value of contrast-enhanced fluid-attenuated inversion-recovery MRI for intracranial tumors in comparison with post-contrast TlW spin-echo MRI

• Published in: Chinese medical journal 2006, Vol.119 (6), p.467-473
• Main Author: ZHOU Zheng-rong SHEN Tian-zhen CHEN Xing-rong PENG Wei-jun
• Format: Article
• Language: English
• Subjects: MRI检查; 病理机制; 诊断方法; 颅内肿瘤
• ISSN: 0366-6999; 2542-5641

Background Contrast-enhanced fluid-attenuated inversion-recovery （FLAIR） magnetic resonance imaging （MRI） has been reported to have higher sensitivity for detecting leptomeningeal disease compared with contrastenhanced T1-weighted MRI （CE T1WI）. However, currently there are no studies showing the potential value of clinical applications of contrast-enhanced FLAIR （CE FLAIR） sequence in diagnosing intracranial tumors in a larger group of patients. The purpose of this study was to evaluate the diagnostic value of CE FLAIR in comparison with CE TlWI for intracranial tumors and to provide more information for clinical diagnosis and therapy. Methods One hundred and four consecutive cases of intracranial tumors referred for CE brain MRI were analyzed with regard to FLAIR and TlWI pre- and post-administration of Gd-DTPA. The CE FLAIR and CE TlWI were evaluated independently by two radiologists for the number of examinations with one or more enhanced lesions, the number and location of enhanced lesions per examination, signal-to-noise ratio （SNR） and contrast-enhancement ratio （CER） of lesions, as well as the size and extent of the enhanced lesions. Results In 98 of 104 cases, enhanced lesions were seen both on the FLAIR and TlW images. More lesions were seen on CE TlWI （n=120） than those on CE FLAIR sequence （n=llT）, but no differences of statistical significance were found between the two sequences （/＇〉0.05）. Four lesions were revealed only on the CE FLAIR images whereas 7 lesions were only found on CE TlWI. Enhanced lesions located in the cerebral hemisphere or the forth ventricle were revealed much more on CE T1WI than on CE FLAIR images. However, CE FLAIR images may be useful in showing superficial abnormalities and those located in the sulcus or lateral ventricle. The CER and contrast-to-noise ratio （CNR） on CE T1WI was significantly higher （t=7.10, P=0.00; t=9.67, P=0.00, respectively）, but grey matter/white matter contrast was lower （t=-2.46, P=-0.02） than those on CE FLAIR images. The SNR did not show any statistically significant difference between the two sequences （t=-1.1, P=-0.27）. The size and extent of lesions on the CE FLAIR images were significantly larger than those on CE TIWI （t=4.13, P=0.00）.