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Surgical Predictors of Reduced Marginal Reflex Distance After Upper Blepharoplasty.

Bunyada Putthirangsiwong1, Blake Katsev1, Kenneth D Steinsapir1

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Upper blepharoplasty can cause a reduction in the marginal reflex distance (MRD1), potentially leading to ptosis. Orbicularis oculi muscle removal during surgery significantly increases the risk of this MRD1 reduction.

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Area of Science:

  • Ophthalmology
  • Plastic Surgery

Background:

  • Ptosis, or drooping of the eyelid, can be a complication following upper blepharoplasty.
  • The marginal reflex distance (MRD1) is a key measurement for assessing eyelid position.

Purpose of the Study:

  • To determine the incidence of postoperative MRD1 reduction after upper blepharoplasty.
  • To identify surgical factors that may predict MRD1 reduction.

Main Methods:

  • A cross-sectional study involving patients over 18 undergoing upper blepharoplasty.
  • Exclusion criteria included prior ptosis or brow surgery.
  • Digital measurement of MRD1 and documentation of surgical variables like muscle, fat, and skin excision.

Main Results:

  • 15% of patients experienced an MRD1 reduction of >1 mm.
  • Orbicularis muscle removal was the only significant predictor of MRD1 reduction (OR=8.2, p<0.05).
  • The mean MRD1 showed a slight but statistically significant increase postoperatively.

Conclusions:

  • A 15% incidence of MRD1 reduction was observed after upper blepharoplasty.
  • Orbicularis oculi muscle removal is significantly associated with postoperative MRD1 reduction.