Related Experiment Video
Updated: Jun 27, 2025
Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Changes in Perceived Emotions in Facial Paralysis Patients After Depressor Anguli Oris Excision
Samuel P O'Rourke1, Taylor J Stack1, Jonas R Miller2
1University of North Carolina School of Medicine, Chapel Hill, North Carolina, U.S.A.
Objectives:
Depressor anguli oris (DAO) excision can improve clinician-graded, objective, and patient-reported smile outcomes in patients with nonflaccid facial paralysis (NFFP). However, no prior research has studied changes in perceived emotions after surgery. This study quantifies changes in perceived emotions with smiling after DAO excision in the largest case series presented to date.
Methods:
Prospectively collected data from patients with NFFP who underwent DAO excision at a tertiary care facial nerve center were reviewed. Patient-reported, clinician-graded, and objective smile metrics were compared before and after surgery. Videos of faces at rest and while smiling were analyzed by artificial intelligence-derived facial expression analysis software to quantify perceived emotions.
Results:
Sixty-eight patients underwent isolated DAO excision between August 2021 and August 2023. Patients conveyed significantly more perceived happiness with smile and at rest after surgery (p < 0.001 and p = 0.012, respectively). DAO excision improved oral commissure excursion (p < 0.001), dental show (p < 0.001), and smile angle (p < 0.001) symmetry. Patients reported significant improvements in smiling and social function after surgery.
Conclusions:
This study demonstrates DAO excision increases perceived happiness conveyed by patients with NFFP while smiling and at rest. It confirms improved objective, clinician-graded, and patient-reported smile outcomes after surgery.
Level Of Evidence:
4 Laryngoscope, 134:4028-4035, 2024.
