Role of 18F-FDG PET in demonstrating disease burden in patients with tuberculous meningitis.

OBJECTIVE: To study the role of 18fluoro-deoxy glucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan in documenting the disease burden in patients with tuberculous meningitis (TBM), and compare these findings with conventional imaging and magnetic resonance imaging (MRI). SUBJECTS AND METHODS: Ten patients with definite TBM were prospectively recruited. The severity of TBM was graded into stage I to III. The patients were subjected to whole body 18F-FDG PET/CT imaging and MRI brain. 18F-FDG PET/CT results were compared with the findings of brain MRI and other convectional imaging modalities (ultrasonography of abdomen and chest radiograph). RESULTS: There were ten patients with TBM whose median age was 27 (14-55) years, and the median duration of illness was 4 (0.5-8.0) months. Two patients were in stage I, six in stage II, and two in stage III meningitis. 18F-FDG PET/CT confirmed the cranial MRI findings in six patients, revealed additional brain lesion in one and did not detect the existing MRI lesions in three patients. 18F-FDG PET/CT however detected additional lesions in vertebrae, spinal cord and lymph nodes which were not seen on the conventional imaging. CONCLUSION: 18F-FDG PET/CT has a complementary role to MRI for detection of cranial lesions and is more sensitive in detecting the extra cranial tuberculosis burden in the patients with TBM.