Figure 4.

(a–h): Coronal, sagittal and axial MRI in a 6-year-old girl with confirmed pulmonary TB. Coronal (a–c) and sagittal STIR (d,e) images demonstrate characteristic low signal TB lymphadenopathy (white arrows) in the right and left paratracheal, and hilar regions. These can be compared with the higher signal axillary lymph nodes in image (c) which represent the appearance of non-TB nodes. Axial post gadolinium T1 at the level of the aortic arch (f) demonstrates that the STIR low signal lymphadenopathy in (a–e) demonstrates rim enhancement (white arrows), typical of centrally necrotic TB nodes. In addition, there is homogenous enhancement of a dense left consolidation (star) with an area of non-enhancing low signal (black arrow), in keeping with parenchymal breakdown within the consolidation. The axial STIR (g) and corresponding gadolinium enhanced T1 (h) at the lower zone of the lungs demonstrates an intermediate-to-high STIR signal enhancing consolidation posteriorly on the right (star) in keeping with viable lung; an intermediate STIR signal, poorly and heterogeneously enhancing consolidation on the left (star) in keeping with at risk lung; and a T2 low STIR signal non-enhancing focal area on the left (black arrow) typical of TB necrosis (this is the opposite to the STIR signal of an abscess, which would be bright).