[CT findings in the recurrent oral maxillofacial tumors eroding the central skull base]

OBJECTIVE:To domonstrate the CT manifestations of the recurrent oral maxillofacial tumors invading the middle skull base.METHODS:CT detections with axial (37 cases) and coronal (26 cases) scans were performed in thirty-seven patients who suffered from the recurrent oral maxillofacial tumors.All lesions were proven histopathologically.RESULTS:Four patterns of the central skull base erosion showing on CT images were encompassed:1.resorption of the outer cortical margin (5 cases);2.resorption of both outer and inner cortical laminae (24 cases);3.enlargement of the ovale foramen (3 cases);4.combined of sclerosis and resorption of the skull base (5 cases).The sphenoid greater wing involvement by the recurrent lesions was more frequently seen in our series (36 cases).Twenty four patients with the recurrent lesions were identified as following intracranial structures affected:the cavernous sinus (n=16),temporal lobe (n=15),and pituetary (n=1).CONCLUSION:It is believed that involvement of the intracranial structures is in close relationship with the aforementioned erosive patterns of the central skull base.The role of CT examination for evaluating the oral maxillofacial recurrent lesions invading the central skull base is very important.