Favorable Outcome Perception in Facial Selective Neurectomy

Objective: Facial selective neurectomy (SN) improves facial function by denervation of muscles antagonistic to the smile in nonflaccid facial paralysis (NFFP) patients. This study aims to assess whether and which objective facial function metrics affect favorable SN outcome in NFFP patients, as perceived by facial nerve (FN) practitioners.

Study design: Retrospective cohort study.

Setting: NFFP patients who underwent SN at the facial nerve center.

Methods: Standardized preoperative and postoperative facial photographs of patients undergoing SN were analyzed using clinician-graded measures (eFACE) and automated facial measurement (Emotrics). Favorable outcome was ranked subjectively by 3 independent FN practitioners. Correlations between objective metrics and favorable subjective outcome were examined.

Results: Fifty-eight SN cases were included. Oral commissure excursion with smile, interlabial distance, and lower lip movement were all considered statistically significantly important for favorable outcome perception. Each +1 mm of smile excursion increases the odds of a favorable outcome by 75.4% (odds ratio [OR]: 1.754). Each +1 mm of interlabial distance asymmetry decreases the odds of a favorable outcome by 24.7% (OR: 0.753). Each +1-point change in lower lip movement eFACE score increases the odds of a favorable outcome by 2.7% (OR: 1.027).

Conclusion: Several smile metrics contribute to favorable SN outcome perception among FN practitioners. Smile excursion, interlabial distance, and lower lip movement were significant predictors of success. These observations may be extrapolated to other facial reanimation interventions and serve surgeons and patients during counseling and expectation management, and during surgery.