Nuclear medicine
Fused PET-CT
Non-contrast CT
Large lung tumour adjacent to the aortic arch, extending to the aorto-pulmonary window and the expected location of the left recurrent laryngeal nerve. On plain CT, there are features of left sided vocal cord palsy, with paramedian position of the cord and enlarged laryngeal ventricle (arrow). No increased PET uptake is seen in the paralysed cord, consistent with absence of tumour there. There is increased PET uptake in the normal cord (arrow), secondary to increased physiological activity as a compensatory mechanism.