Background: Nasopharyngeal carcinoma (NPC) may infiltrate the pterygopalatine fossa (PPF) and the maxillary nerve. This study illustrates involvement of the maxillary nerve in the PPF with perineural spread to the cavernous sinus.
Methods: One hundred and fourteen patients with proven NPC were studied using magnetic resonance imaging (MRI) and computed tomography (CT). The images were retrospectively reviewed for PPF infiltration and maxillary nerve involvement.
Results: Seventeen (15%) patients showed infiltration of the PPF. Four patients had maxillary nerve involvement and a perineural spread to the cavernous sinus. Of the 17 patients with PPF infiltration, 8 (47%) patients showed hypoesthesia in the distribution of the infraorbital nerve. All 4 patients with contrast-enhancement of the maxillary nerve exhibited infraorbital neuropathy.
Conclusion: Infiltration of the maxillary nerve in the PPF with intracranial spread is uncommon but should be suspected in patients with infraorbital neuropathy. This is important as it affects both prognosis and radiation treatment planning.