Isolated abducens nerve palsy due to acute sphenoiditis

The aim of this paper was to describe a patient affected by isolated abducens nerve palsy and visual disturbances due to a bilateral acute paranasal sinus infection. Patient medical records and imaging studies were reviewed, as well as the literature on the topic. Our patient presented an upper respiratory tract infection, associated with fever, severe progressively worsening headache and diplopia. Physical examination demonstrated right-sided sixth cranial nerve palsy. Imaging studies were consistent with bilateral pan-sinusal inflammatory disease. The patient was initially treated with antibiotics and betamethasone; upon 48 hours, due to the persistence of symptoms, she underwent sinuses drainage by functional endoscopic sinus surgery. After the complete resolution of the infection, at the control MRI study a Dorello's canal was demonstrated on the right side. Cranial nerve palsies associated to paranasal sinus infection have already been reported; however in this case we evidenced a direct correlation between the sinusal (sphenoidal) involvement and the abducens nerve.