Pictorial review: Radiology of the masticator space

The suprazygomatic portion of the masticator space (MS) or the temporal fossa is superficial and accessible to clinical assessment. The nasopharyngeal masticator space or infratemporal fossa is deep and can only be adequately evaluated by imaging studies. Infection secondary to odontogenic abscess or malignant otitis extema commonly affects this space. Primary tumours may arise from both soft tissues and bony structures. Malignant invasion of the MS from surrounding structures may take place. The delineation of these lesions is readily achieved by both computed tomography (CT) and magnetic resonance imaging (MRI). However, perineural infiltration and intracranial extension is better seen on MRI. Accurate assessment of disease extent is necessary for drainage procedures, surgical intervention or radiotherapy planning.