The Application Of MRI Contrasted Subtraction In Tuberculosis Meningitis

Objective: To assess the clinical application of magnetic resonance imaging(MRI) contrast-enhanced subtraction in tuberculous meningitis (TBM).Methods: Thirty patients with TBM were examined by using MRI with T1-weighted MR sequences before and after intravenous administration of Dimeglumine Gadopentetate (Gd-DTPA), and digital subtraction was performed on selected images. 120 abnormally enhanced meninges were randomly selected on both post-contrast T1 WI and subtraction images, and the maximum length and the relative signal intensities were measured respectively on subtraction images and conventional contrast-enhanced T1WI in those 120 different anatomic levels. The data were analyzed with statistical software. Imaging findings were compared between subtraction images and conventional contrast-enhanced MRI.Results: Subtraction images was better than routine contrast-enhanced MRI in demonstrating the abnormal meninges. The abnormal enhanced meninges showed continuous enhancement patterns on subtraction images, while short segmental enhancement was most frequently observed on routine contrast-enhanced T1WI. The abnormal meningeal enhancement length showed statistical difference between the two different imaging methods (PO.01). All the meningeal lesions had higher relative signal intensities on subtraction images than on routine contrast-enhanced MRI (PO.01).Conclusion: MR contrast-enhanced subtraction technique is an important and easy postprocessing method which can improve the demonstration of meningeal abnormalities in TBM, and thus it can be recommended as the early diagnostictool for TBM.