Aberrant facial nerve regeneration (AFR): an under-recognized cause of ptosis

Abstract

INTRODUCTION: Aberrant facial nerve regeneration (AFR) following facial nerve palsy may give rise to ptosis because of increased orbicularis tone. We describe a series of patients presenting with ptosis where the underlying aetiology of AFR was often not recognized by the referring clinicians. METHODS: Retrospective case review. RESULTS: A total of 15 cases with ptosis, secondary to AFR, were seen at the Royal Adelaide Hospital Oculoplastic Clinic between 2000 and 2002. Of these, 10 (67%) were referred by general ophthalmologists. Ptosis was the only reason for referral in 11 patients (73%) and features of AFR or a past history of facial nerve palsy were not mentioned in seven referrals (overall 46%). All patients reported a previous facial palsy. The palpebral aperture was reduced on the affected side with reduction in both upper and lower margin reflex distance (MRD) by a mean of 1.5±0.7?mm (P<0.001) and 1.0±0.3?mm (P<0.001), respectively. The orbicularis tone was increased and strength reduced on the affected side in all patients. However, none had lagophthalmos. Signs of AFR were demonstrated in all patients with either an increase in ptosis or eyelid closure on the affected side during cheek puffing. CONCLUSION: Patients with AFR following facial nerve palsy may present with ptosis without recognition of the underlying aetiology. Signs of AFR ptosis include a decreased palpebral aperture with a reduced upper and lower MRD. The diagnosis can be established with demonstration of an increase in ptosis during cheek puffing. Recognition of AFR is important in these cases owing to the implications for management and post-operative patient satisfaction.