Facial Neuropathy in Patients with Recurrent Painful Ophthalmoplegic Neuropathy

Involvement of non-ocular motor cranial nerves, such as the trigeminal, facial or hypoglossal nerves, has rarely been reported in recurrent painful ophthalmoplegic neuropathy (RPON). This study aimed to determine the incidence and clinical significance of multi-cranial nerve involvement in RPON.

Eight patients (females = 5; mean age = 53.3 ± 15.6 years) who met International Classification of Headache Disorders-3 diagnostic criteria for RPON were enrolled at a single tertiary hospital. Repeated evaluations were performed for differential diagnosis, including cranial nerve examination, brain MRI, CSF analysis and serologic testing for autoimmune and tumor markers. Clinical features, neuroimaging findings and laboratory results were reviewed.

Five patients (62.5%) had a present or past history of migraine. Among 25 ophthalmoplegic attacks, the abducens nerve was most frequently affected (60%), followed by the oculomotor nerve (32%). Most attacks were preceded by ipsilateral headache (4.0 ± 2.9 days; 88%). Facial nerve involvement was common (7/8, 87.5%); two patients had three recurrent facial neuropathies on the same side, and one showed simultaneous ipsilateral oculomotor and facial neuropathies. All facial neuropathies were peripheral. Of the three patients who underwent MRI for facial neuropathy, two demonstrated focal facial nerve enhancement. Postauricular pain usually preceded facial neuropathy and lacked migrainous features. Both facial neuropathy and ophthalmoplegia resolved within days to weeks.

Facial neuropathy may be more common in RPON than previously recognized. Despite similarities to Bell's palsy, our findings support considering facial neuropathy within the RPON spectrum and suggest that recurrent, multifocal and alternating cranial neuropathy may underlie its pathophysiology.