MRI OF EXTRACRANIAL MASSES IN CHILDREN - THE USEFULNESS OF GADOLINIUM-CHELATE ENHANCEMENT

Objective. This study evaluated the usefulness of gadolinium (Gd) chel ates in magnetic resonance imaging (MRI) of extracranial pediatric mas s lesions. Materials and methods. Seventy-five MRI studies were obtain ed on 60 children (mean age 5.06 years) with pathologically proven mas s lesions. Post-contrast T1-weighted (T1W) images were compared with p re-contrast T1-weighted, T2-weighted (T2W) and both T1W and T2W images . They were evaluated for their ability to demonstrate lesion margins and extent, to add additional information, and to increase confidence in or change a diagnosis. In all patients post-contrast images were al so evaluated for degree and pattern of enhancement. Results. Malignant lesions enhanced much more intensely than benign lesions (P < 0.0005) . Lack of enhancement was seen only in benign lesions. a heterogeneous pattern of enhancement was more frequently seen in malignancy (P < 0. 05). Additional information was provided on Gd-enhanced T1W images in 36% of cases compared to unenhanced T1 and T2W images. Diagnostic conf idence was improved in 29%. The Gd-enhanced images changed the diagnos is correctly in 5% and incorrectly in 1%. Conclusion. Post-contrast im ages clarified specific issues, better defined lesion extent and margi ns in a majority of cases, and gave additional useful information in s elected cases.