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Updated: Mar 19, 2026

Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Association of Eyelid Position and Facial Nerve Palsy With Unresolved Weakness
Kunal R Sinha1, Daniel B Rootman2, Babak Azizzadeh3
1Jules Stein Eye Institute, Division of Orbital and Ophthalmic Plastic Surgery, University of California, Los Angeles.
Importance:
Understanding the prevalence and clinical features of eyelid malpositions in facial nerve palsy (FNP) may inform proper management of patients with FNP and supplement our knowledge of eyelid physiology.
Objective:
To describe eyelid malposition in FNP.
Design, Setting, And Participants:
In this retrospective cohort study, patients with FNP seen at the Center for Advanced Facial Plastic Surgery and Jules Stein Eye Institute between January 1, 1999, and June 1, 2014, were reviewed for study inclusion. Data collection was performed between June 1, 2014, to August 1, 2014, and data analysis was performed between June 15, 2014, to September 1, 2015. The distances from the center of the pupil to the upper eyelid margin (marginal reflex distance 1 [MRD1]) and to the lower eyelid margin (marginal reflex distance 2 [MRD2]) were measured on photographs of patients in the primary position and with full smile. Eyelid asymmetry, retraction, ptosis, synkinesis, and severity and duration of FNP were assessed. Eligible participants were adults with FNP at a private tertiary care clinic with primary position photographs. Exclusion criteria included prior history of procedures or medical conditions that could alter eyelid position.
Results:
The 52 included patients were predominantly female (38 [73%]), with a mean (SD) age of 44.1 (13.8) years. Of this group, 34 patients (65%) were white, 8 (15%) were Asian, 8 (15%) were Hispanic, and 2 (4%) were African American. Retraction (MRD1, >5.0 mm) was present in 8 patients (15%), 3 of whom had eyelid asymmetry (MRD1, >1.0 mm). Overall, total asymmetry of greater than 1.0 mm was present in 14 patients (27%), with the FNP side higher in 12 (23%). Compared with those without asymmetry, patients with eyelid asymmetry were significantly more likely to have contralateral ptosis (42% vs 2.5%, P < .001) but did not have a significantly shorter duration of FNP (12.3 months vs 13.8 months, P = .82). Ptosis was noted in 4 patients and was also unrelated to duration of FNP (9.6 months in patients with ptosis vs 13.6 months in those without, P = .60). Synkinesis was found in 24 patients (46%), but none had concomitant ptosis. Severe FNP (House-Brackmann score, ≥4) was present in 28 patients (54%), and these patients were 20 times more likely to have asymmetry greater than 1.0 mm, often with the FNP side higher.
Conclusions And Relevance:
Upper eyelid asymmetry is common in FNP. In most of the patients in this study, the FNP side was higher without demonstrating retraction, and the contralateral side was ptotic. Thus, contralateral ptosis surgery may benefit these patients. Furthermore, patients with severe facial weakness were more likely to have eyelid asymmetry, suggesting that the ability of the eyelid position maintenance system to adapt to weakness of eyelid protractors may be limited by the severity of this weakness.
Level Of Evidence:
3.
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