Characteristic magnetic resonance imaging low T2 signal intensity of necrotic lung parenchyma in children with pulmonary tuberculosis
Purpose: To show that necrotic areas of the lung demonstrated on computed tomographic scanning in children with primary pulmonary tuberculosis (TB) may be of low signal intensity on T2. Materials and Methods: Review of magnetic resonance imaging scans (T1/T2/STIR/postgadolinium T1) in 6 children scanned because of low-density necrotic areas demonstrated on computed tomography scanning prior to bronchoscopic confirmation of pulmonary TB. Results: Abnormalities included airspace consolidation in 6 children (100%); central necrosis in 6 children (100%); nodules in 2 children (33.3%); and lymphadenopathy in 6 children (100%). Low T2 signal in the areas of necrosis was demonstrated in all 6 children (100%) and in an area of at least 2×2 cm; 1 child also showed an area of high signal (16.67%). Airspace consolidation demonstrated T2 high signal in all the children (100%). Both children with nodules demonstrated at least 1 nodule with a low signal in addition to the majority of high-signal nodules. Post gadolinium, the consolidation and all high-signal nodules demonstrated enhancement, whereas the areas of lung necrosis and low signal nodules showed no enhancement. CONCLUSION: Lung parenchymal necrosis in primary pulmonary TB in children may be of low signal intensity on T2 and STIR magnetic resonance imaging. This may be distal to lymphobronchial obstruction and is probably due to the caseating necrosis. Copyright © 2012 by Lippincott Williams & Wilkins.