Related Experiment Video
Updated: Jun 26, 2026

Surgical Correction for Pediatric Epiblepharon and Trichiasis
Published on: July 8, 2025
[Decrease of upper eyelid levator muscle function after involutional ptosis and dermatochalasis surgery]
Eliana Forno1, Eurípedes da Mota Moura, Suzana Matayoshi
1Faculdade de Medicina da Universidade de São Paulo - São Paulo (SP) - Brasil.
Purpose:
To evaluate the differences between upper eyelid levator muscle function (UELMF), margin reflex distance (MDR1), and eyelid crease height (ECH) before and after ptosis and dermatochalasis surgery.
Methods:
Forty-four patients with blepharoptosis and dermatochalasis were enrolled.
Intervention:
An exploration of the levator tendon (LT) during a blepharoplasty procedure in patients with blepharoptosis and dermatochalasis and in case of its disinsertion, the tendon was reattached to the tarsus. Measured outcome: The differences between UELMF, MDR1, ECH before and after surgery were evaluated bilaterally. Dependency between both eyes was corrected by generalized estimating equations. Pearson correlation was used to evaluate the dependency of the two eyes regarding UELMF, MDR1 and ECH.
Results:
There was a statistical significant difference between the measures of UELMF before and after surgery with excursion decreasing by a mean value of 1.1 mm after the procedure (P<0.001). Measures of MDR1 showed an increase by a mean of 1.6 mm and ECH decreased by a mean of 3.97 mm (P<0.001). We found a significant correlation between both eyes for all analyzed eyelid variables, both before and after surgery. Correlation before surgery was stronger for the group without previous surgery. The same results for correlation were found for the amount of disinsertion (P>0.001).
Conclusions:
Upper eyelid levator muscle function decreases after ptosis surgery.
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