[A case of recurrent headache and ophthalmoplegia with a contrast-enhanced lesion of the oculomotor nerve in the cavernous region: an atypical phenotype of recurrent painful ophthalmoplegic neuropathy].

The patient was a 14-year-old boy with two previous episodes of self-remitting right ophthalmoplegia with right temporal pain at ages 9 and 12. In 2019, he developed right eyelid ptosis and diplopia 2 days after a pulsating right-sided temporoparietal headache. Recurrent headaches with ophthalmoplegia responded to high-dose steroid therapy, and the clinical features resembled recurrent painful ophthalmoplegic neuropathy (RPON). RPON generally presents with MRI findings of hypertrophy and inflammation at the root of the oculomotor nerve, a vulnerable site of the blood-brain barrier. However, the imaging features in this case were different from those in typical cases of RPON, and oculomotor nerve inflammation was found in the cavernous sinus. The order of onset of headache and oculomotor nerve palsy differed in each recurrence, suggesting that both autoimmune and vascular mechanisms may have been involved in the onset of the disease in our case.