Imaging features of sinonasal tumors on positron emission tomography and magnetic resonance imaging including diffusion weighted imaging: A pictorial review

Introduction: Sinonasal inflammatory conditions account for a major component of head and neck pathologies, whereas neoplasms involving the sinonasal region make up only 2–3% of all head and neck lesions. The symptoms of sinonasal tumors are nonspecific; imaging plays a critical role in distinguishing benign and malignant disease and may illustrate characteristic radiological features of specific sinonasal tumors. Objective: Aim was to determine the utilization of multimodality imaging, specifically the metabolic information provided by 18-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET/CT) and diffusivity characteristics seen with diffusion weighted images (DWI) of magnetic resonance imaging (MRI), in a wide range of benign and malignant sinonasal tumors drawn from over 200 sinonasal lesions from our institution and supplemented by the literature. Conclusion: In this pictorial essay, we have reviewed common imaging characteristics of frequently encountered in sinonasal tumors and divided them into benign and malignant categories to facilitate creation of focused differential diagnoses.