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Published on: September 20, 2024
Aesthetic Correction of Mild Blepharoptosis: Balancing the Effect of Hering's Law
1From the Facial and Cervical Center, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College.
Background:
Disregarding the influence of Hering's law of equal innervation, which dictates conjugate movement of the eyelids during saccadic eye movements, in blepharoptosis correction leads to unsatisfactory surgical outcomes. The authors report a systemic assessment and surgical method to balance the Hering's law effect in mild blepharoptosis.
Methods:
Comprehensive assessment included a detailed examination, ptosis correction sequence, levator complex plication, and repeated intraoperative adjustments. Surgical efficacy and symmetry differences were assessed by comparing margin reflex distance 1 between patients with and without Hering's law effect.
Results:
A total of 83 patients with mild ptosis were evaluated, and the average follow-up was 5.3 months. In evaluating the need for secondary blepharoplasty, 23.1% of patients (9 of 39) in the Hering's law-positive group were dissatisfied with previous surgery, whereas only 6.8% of patients (3 of 44) in the Hering's law-negative group sought revision. Due to continuous intraoperative adjustments, ptosis and eyelid symmetry showed significant improvement in both groups, as effects of Hering's law were effectively balanced intraoperatively.
Conclusions:
Hering's law plays a crucial role in the aesthetic correction of mild ptosis. Neglecting the effect of Hering's law can lead to the need for revision surgery. A systemic approach to assessment and surgery, comprising a comprehensive examination, a structured ptosis correction sequence, levator complex plication, and repeated intraoperative adjustments, is essential for effectively balancing the effects of Hering's law. Due to continuous intraoperative adjustments, ptosis and eyelid symmetry showed significant improvement in both Hering's law-positive and Hering's law-negative groups.
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