Abducens nerve paralysis: a potential presentation of sphenoid sinus cancer.

The sphenoid sinus is the paranasal sinus most commonly implicated when cranial neuropathies are present. Two patients presenting with sixth nerve paralysis secondary to sphenoid sinus involvement are presented. One patient had a primary sphenoid sinus tumor, and the other a metastasis from a bronchogenic carcinoma. Of the two patients, one carried the diagnosis of idiopathic sixth nerve paresis and had had a normal sinus x-ray film and CAT scan done previously. Even in the absence of positive radiographic findings, the high clinical suspicion of sinus malignancy must be maintained in patients manifesting abducens nerve paralysis. In these patients, the petrous apex and cavernous sinus "silent area" must be diligently evaluated. For the patient to have any chance for palliation or potential cure, the tumor must be diagnosed as soon as possible.