[Differential diagnosis between infection and neoplasm of the infratemporal fossa]

Because there are many similarities in infection and neoplasm of the infratemporal fossa (ITF), it is difficult to differentiate between these two diseases. By analysing 28 cases of the ITF lesions (8 cases of infection, 20 cases of neoplasm) the authors find the following points are important to differentiate between infection and neoplasm of the ITF. 1. The patients suffering from ITF infection almost all have odynophagia, while the patients suffering from the ITF neoplasm have no such symptom. The latter presents numbness in branches of the fifth nerve, while the former scarcely exhibits this symptom. 2. In the ITF neoplasm the mass could be found by CT or MRI, while in the ITF cellulitis no mass could be found. Although CT or MRI could find the mass in the ITF abscess, at the same time CT definitely could find some imaging signs which signify infection such as abscess formation (lucency) and gas bubbles. CT could find adjacent bone destruction in most ITF neoplasms, while this is rare in (ITF) infection. MRI is very helpful in differentiating between these two.