[Three cases of abducens nerve palsy accompanied by Horner syndrome].

Purpose: To report three cases of nasopharyngeal carcinoma, exhibiting abducens nerve palsy and Horner syndrome during the medical treatment of the tumor, whose invasive cavernous sinus lesions could be detected.
Subjects: The patients were two men and one woman who were referred to our department with complaints of diplopia during the clinical course of nasopharyngeal carcinoma.
Results: Right abducens nerve palsy, Horner syndrome, and impairment of the 1st division of the trigeminal nerve were recognized in all patients. Magnetic resonance imaging (MRI) revealed invasive lesions in the right cavernous sinus in all three patients, with iso-intensity on T1-weighted images, which were enhanced by gadolinium.
Conclusions: The abducens and sympathetic nerves run closely together in the cavernous sinus. Nasopharyngeal carcinoma is apt to invade the cavernous sinus and often impairs the abducens nerve. Therefore the presence of Horner syndrome and trigeminal palsy in combination with abducens nerve palsy should be cautiously investigated to confirm the existence of the cavernous sinus lesions.