Fig. 32

Infected necrotic lymph node metastasis (arrows) from oropharyngeal cancer misdiagnosed as suppurative lymphadenitis on axial T2-weighted (a) and fat-suppressed post-contrast T1-weighed images (b) and ADC (c). The patient had signs and symptoms of an acute neck infection. Low ADC suggests that the non-enhancing fluid collection is purulent. The cancer was not known at the time of imaging. Note the necrotic lymph node without signs of infection on the contralateral side (dotted arrow in b), suggestive of malignancy