HEAD AND NECK IMAGING Imaging of the pharynx and larynx

Summary  An overwhelming majority of pharyngeal and laryngeal tumours are squamous cell carcinomas, which arise from the mucosal layer. A submucosal lesion should alert the radiologist to the possibility of atypical histology.  Early mucosal lesions can be easily missed on imaging and are best detected by direct visualisation because these areas are readily accessible to the endoscopist. The imaging appearance always requires correlation with the endoscopic appearance.  Submucosal spread is best visualised on cross-sectional imaging, and the primary role of the radiologist is to accurately stage the extent of disease, which directly influences treatment planning.  Identification of cartilage involvement in laryngeal carcinoma is crucial, but it is not without pitfalls.  Post-treatment imaging appearances are variable and can mimic a tumour. Followup CT/MRI, positron emission tomography imaging and biopsy all play a complementary role to clinical or endoscopic assessment in such cases.  Perineural spread with intracranial extension, skull base involvement and intraorbital extension is often seen with some head and neck malignancies. The radiologist should be alert to these possibilities and carefully inspect the relevant areas because these findings can make a significant impact on patient management.  Both CT and MRI are widely used for tumour staging and are sometimes complementary.