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Updated: Jan 20, 2026

In Vivo Confocal Microscopy: A Standard Operating Procedure for the Detection of Demodex Mites at the Eyelid Margin
Published on: July 3, 2025
Brow height asymmetry before and after eyelid ptosis surgery
Justin N Karlin1, Daniel B Rootman1
1Department of Orbital and Ophthalmic Plastic Surgery, Doheny Eye Institute and Stein Eye Institute - UCLA, USA.
Background:
In the setting of upper eyelid ptosis, asymmetric eyebrow position may be observed and may contribute to overall facial asymmetry. In this study, the authors aim to elucidate the prevalence and predictors of brow height asymmetry in the setting of ptosis and to determine the effect of eyelid surgery on brow height asymmetry to guide preoperative evaluation and informed consent.
Methods:
In this cohort study, patients undergoing posterior approach ptosis surgery, unilateral or bilateral, with or without blepharoplasty, were included. Exclusion criteria included heterotropia, history of brow surgery, and history of previous ptosis surgery. Clinically significant eyelid asymmetry was defined as a difference greater than or equal to 1 mm between right and left margin reflex distance 1 (MRD1) values. Brow asymmetry was defined as difference in pupil-to-brow (PTB) distance of greater than or equal to 3.5 mm.
Results:
The sample included 228 patients. Preoperative brow asymmetry was found in 17.1% of the sample. Notably, half of the patients with preoperative brow asymmetry were found to have postoperative brow asymmetry. Logistic regression indicated that preoperative brow asymmetry was a predictor of postoperative brow asymmetry (odds ratio = 17.03, p < 0.01). In subgroup analysis of those with preoperative brow asymmetry, postoperative eyelid asymmetry was a predictor of postoperative brow asymmetry (odds ratio = 5.58, p < 0.01). No variables in the current investigation were found to predict brow symmetry in those with preoperative brow asymmetry.
Conclusion:
Understanding the limitations of ptosis surgery in altering brow symmetry helps manage patient expectations, prepare informed consent, and guide surgical and postsurgical planning.
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