Upper eyelid weighting for facial palsy results in contralateral upper eyelid elevation

Abstract

Purpose : We examine the effect of eyelid weighting on the position of the ipsilateral and contralateral upper eyelid.

Methods : This cross-sectional cohort study included patients with unilateral facial palsy who underwent surgical upper eyelid weight implantation. Photographs were obtained in primary position parallel to the plane of the camera. The primary outcome measures were ipsilateral and contralateral margin to reflex distance 1 (MRD1), preoperatively and postoperatively. Postoperative MRD1 difference (symmetry) was assessed as a secondary outcome measure. Weight mass was examined as a covariate in predicting the magnitude of the effect.

Results : Twenty-two patients (16 female, 6 male) met inclusion criteria. Following eyelid weight implantation, contralateral (unweighted) MRD1 increased (mean 0.61 mm, standard deviation [SD] 1.23 mm, p < 0.05). Ipsilateral (weighted) MRD1 decreased, although not significantly (mean -0.41 mm, SD 0.94 mm, p = 0.06). Preoperatively, there was no significant MRD1 difference between the weighted and unweighted sides (mean difference -0.27, SD 1.94 mm, p = 0.52). Postoperatively, there was a significant difference in MRD1 between the weighted and unweighted eyelids (mean -1.29, SD 1.87 mm, p < 0.05). Weight mass was not a significant predictor of change in ipsilateral or contralateral MRD1 (p = 0.54, p = 0.96, respectively) following surgery.

Conclusions : Patients with facial nerve palsy undergoing unilateral insertion of an eyelid weight experience contralateral eyelid elevation, and demonstrate decreased postoperative upper eyelid height symmetry. These data highlight a heretofore undescribed manifestation of Hering’s law, and add to the overall understanding of how eyelid height is regulated.

This is a 2021 ARVO Annual Meeting abstract.

 

Figure 1. Representative images from two patients. The above image is preoperative and the lower image is postoperative. The white asterisk denotes the side where the weight was implanted.

 

Figure 2. Left panel shows that the mean MRD1 of the upper eyelid where the weight was implanted, the ipsilateral weighted eyelid, was not significantly different between preoperative and postoperative states (n.s. = not significant). The right panel illustrates that the significant increase (* = p < 0.05) in MRD1 in the contralateral unweighted upper eyelid.