Changes in Perceived Emotions in Facial Paralysis Patients After Depressor Anguli Oris Excision.

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: Level 4 Laryngoscope, 2024.

Mid-Term Effects of Selective Denervation Surgery on Facial Symmetry in Patients with Nonflaccid Facial Paralysis: Intermediate Follow-Up of Rest and Smile Symmetry.

Introduction: Although selective denervation (SD) improves clinician-graded, objective, and patient-reported smile symmetry, changes in resting symmetry have not been comprehensively studied. Objective: To assess mid-term changes in resting facial symmetry after SD, and to evaluate changes in perceived emotions in faces at rest and with smiling. Methods: Nonflaccid facial paralysis (NFFP) patients undergoing SD were studied from September 2021 to October 2022. Patient-reported, clinician-graded, and objective metrics of resting and smile symmetry were quantified. Results: Fourteen patients (median age 59.5 years; median paralysis duration 76.5 months; median follow-up 249.5 days (138-400); average of 5.7 branches sacrificed) underwent SD. Resting oral commissure (OC) symmetry (p = 0.028) and upper lip symmetry (p = 0.030) improved after surgery. In smiling faces, OC excursion (p = 0.004), smile angle (p = 0.016), and dental show (p = 0.012) improved. There were significant increases in perceived happiness at rest (p = 0.006) and with smile (p = 0.002). Clinician grading revealed improved nasolabial fold depth at rest (p = 0.087) after surgery, and patients reported improved facial function and happiness with the decision to undergo surgery. Conclusion: Intermediate follow-up suggests SD can improve objective resting and smile symmetry in patients with NFFP. After surgery, patients' faces convey more happiness in repose and with smile.

Predicting Depressor Anguli Oris Excision Outcomes Using Local Muscle Block.

Introduction: Although depressor anguli oris (DAO) muscle block is a useful tool to help predict which patients will respond positively to myectomy, DAO excision outcomes have not been correlated with smile changes after muscle block. Objective: To compare changes in smile symmetry after DAO muscle block with changes after DAO myectomy. Methods: Nonflaccid facial paralysis patients undergoing DAO excision at a tertiary care facial nerve center were prospectively studied from August 2021 to June 2022. Dental show, oral commissure excursion, and smile angle at baseline, after DAO muscle block, and after myectomy, were quantified. Results: Twenty-three patients underwent DAO muscle block followed by myectomy. DAO excision produced improved dental show (p = 0.006) and oral commissure excursion (p = 0.024) symmetry compared with muscle block. A strong correlation exists between changes in oral commissure excursion symmetry after muscle block and after myectomy. Moderate correlations exist for changes in smile angle and dental show symmetry. Conclusion: Although DAO muscle block is a good predictor of smile symmetry after muscle excision, typically excision results in improved dental show and oral commissure symmetry compared with block.