This article is more than 5 years old. Information may no longer be current.

Higher eyelid asymmetry seen in patients with facial nerve palsy

Patients with facial nerve palsy had a higher eyelid asymmetry, and may have a need for contralateral ptosis surgery, according to recent data published in JAMA Facial Plastic Surgery.

“Overall, it is noteworthy that almost three-fourths of patients in this study with unresolved facial weakness after [facial nerve palsy] maintained a relatively symmetric and normal eyelid position despite manifest weakness of the eyelid protractors,” Kunal R. Sinha, BS, from the Jules Stein Eye Institute and division of orbital and ophthalmic plastic surgery at University of California, Los Angeles, and colleagues wrote. “However, the incidence of asymmetry is still higher than one would expect in the general population.”

Sinha and colleagues evaluated 52 patients (73% female; mean age, 44.1 years) with facial nerve palsy (FNP) who were seen between January 1999 and June 2014 at the Center for Advanced Facial Plastic Surgery and the Jules Stein Eye Institute. The researchers measured marginal reflex distance from the center of the pupil to the upper eyelid margin (MDR1), and marginal reflex distance from the center of the pupil to the lower eyelid margin (MDR2), when patients posed in a primary position and with a full smile.

They found retraction in eight patients (MDR1 > 5.0 mm,); of these, three showed eyelid asymmetry, which was defined as MDR1 of less than 1 mm. There were 14 patients (27%) with total asymmetry greater than 1 mm and 12 of these had a higher eyelid on the FNP side. Although patients in the asymmetry and non-asymmetry groups had no significantly shorter duration of FNP (12.3 months vs. 13.8 months; P = .82), patients with asymmetry had a higher likelihood of contralateral ptosis (42% vs. 2.5%, P < .001), with four patients showing ptosis unrelated to FNP duration (9.6 months vs. 13.6 months; P = .6).

The researchers also found synkinesis in 24 patients (46%) without concomitant ptosis and severe FNP in 28 patients (54%) who were “20 times more likely to have asymmetry greater than 1 mm, often with the FNP side higher,” the researchers wrote.

“The totality of these findings again underscores the complexity of the eyelid position maintenance system. This system appears to have the capacity to recalibrate in response to changes in the balance of protracting and retracting forces in the eyelid, but that capacity seems to be limited in the setting of severe facial weakness, leading to an elevated incidence of eyelid asymmetry,” Sinha and colleagues wrote. “More research is clearly required to better understand the complexities of maintaining eyelid position in states of health and disease.” – by Jeff Craven

Disclosure: The researchers report no relevant financial disclosures.