Fig. 9
From: FDG-PET/CT pitfalls in oncological head and neck imaging
a Axial PET/CT image shows a hypermetabolic focus in the left infratemporal fossa (white arrow). This patient was a follow-up case of SCC of the left retromolar trigone, 6 months post radiotherapy, presenting with left V3 distribution pain and dysesthesia. b Corresponding axial contrast-enhanced T1W MR image demonstrates nodular architectural distortion with some enhancement (white arrow) in the left infratemporal fossa. c Corresponding axial CECT image reveals similar morphologic findings as the MR image: an ill-defined area of nodular enhancement (white arrow) in the left infratemporal fossa. The imaging differentials were tumour recurrence along left V3 nerve or post-radiotherapy immature (early) scarring. Surgery was negative for tumour recurrence and careful histologic analysis of the resected specimen yielded fibrotic scar tissue. Follow-up over a period of three years confirmed absence of recurrent disease