Fig. 12

Olfactory neuroblastoma (Esthesioneuroblastoma) in a 41-year-old male presenting with a 2-month history of change in behaviour and anosmia. Coronal bone (a) and soft tissue window (b) CT images demonstrate a large anterior skull base mass centred upon the olfactory neuroepithelium. There is extensive bone destruction of the left and right cribriform plates and turbinates (short arrows, a), and thinning of the medial wall of the left orbit (long arrow, a). There is also inferior extension of the tumour (T) through the ethmoid air cells into the nasal cavity and extending through the left middle meatus into the maxillary sinus (arrowed, b). The soft tissue density of the tumour (T) is distinct from the left maxillary sinus fluid contents (S). Note the fluid density intracranial “capping cysts” at the left frontal lobe (arrowhead, b). Coronal T1WI with contrast (c) depicts a tumour with moderately intense contrast uptake, conforming to a “dumbbell-shape” with a “waist” at the cribriform plate (arrowed, c). Again, note the presence of T1 hypointense “capping cysts” at the intracranial margin, which are a distinguishing feature of these tumours (arrowheads, c)