Airway and Voice Outcomes After Thyroarytenoid Myomectomy for Bilateral Vocal Fold Immobility.

INTRODUCTION: Type 4 posterior glottic stenosis and bilateral vocal fold paralysis are clinically challenging causes of bilateral vocal fold immobility (BVFI) that result in glottic airway obstruction. Established procedures for BVFI typically worsen dysphonia. We hypothesize the use of thyroarytenoid myomectomy (TAM) in the setting of BVFI will improve dyspnea with decreased detriment to voice. METHODS: Eleven unilateral TAM procedures were performed between April 2021 and June 2023 at a single institution. Pre- and postoperative patient reported outcomes were compared. Representative images of maximal glottic opening were analyzed in ImageJ to calculate ipsilateral bowing index (BI), total BI, maximum glottic surface area (MGSA), and maximum opening angle (MOA). Statistical comparisons were performed with paired t-tests when normality was confirmed with Shapiro-Wilk test and otherwise with Wilcoxon signed-rank tests, with threshold for significance of α = 0.05. Interrater reliability for objective glottal measures was compared with intraclass correlation coefficient (ICC). RESULTS: Dyspnea Index improved from mean (standard error) of 24.1 (3.8) to 9.1 (3.3), p = 0.004. Voice Handicap Index-10 improved from 20.0 (4) to 10.3 (3.8), p = 0.011. Glottal Function Index improved from 9.6 (1.4) to 6.3 (1.3), p = 0.017. There was no significant difference in ipsilateral BI, total BI, MOA, and median MGSA. There was good to excellent ICCs for all comparisons (0.83-0.95). CONCLUSIONS: TAM demonstrated significant improvement in symptoms from BVFI while not significantly altering glottal structure. These data suggest TAM improves dyspnea in patients with BVFI without significantly impairing voice. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Electrospun composite-coated endotracheal tubes with controlled siRNA and drug delivery to lubricate and minimize upper airway injury.

Endotracheal Tubes (ETTs) maintain and secure a patent airway; however, prolonged intubation often results in unintended injury to the mucosal epithelium and inflammatory sequelae which complicate recovery. ETT design and materials used have yet to adapt to address intubation associated complications. In this study, a composite coating of electrospun polycaprolactone (PCL) fibers embedded in a four-arm polyethylene glycol acrylate matrix (4APEGA) is developed to transform the ETT from a mechanical device to a dual-purpose device capable of delivering multiple therapeutics while preserving coating integrity. Further, the composite coating system (PCL-4APEGA) is capable of sustained delivery of dexamethasone from the PCL phase and small interfering RNA (siRNA) containing polyplexes from the 4APEGA phase. The siRNA is released rapidly and targets smad3 for immediate reduction in pro-fibrotic transforming growth factor-beta 1 (TGFϐ1) signaling in the upper airway mucosa as well as suppressing long-term sequelae in inflammation from prolonged intubation. A bioreactor was used to study mucosal adhesion to the composite PCL-4APEGA coated ETTs and investigate continued mucus secretory function in ex vivo epithelial samples. The addition of the 4APEGA coating and siRNA delivery to the dexamethasone delivery was then evaluated in a swine model of intubation injury and observed to restore mechanical function of the vocal folds and maintain epithelial thickness when observed over 14 days of intubation. This study demonstrated that increase in surface lubrication paired with surface stiffness reduction significantly decreased fibrotic behavior while reducing epithelial adhesion and abrasion.

Endotracheal tubes with dexamethasone eluting electrospun coating improve tissue mechanical function after upper airway injury.

Corticosteroid-eluting endotracheal tubes (ETTs) were developed and employed in a swine laryngotracheal injury model to maintain airway patency and provide localized drug delivery to inhibit fibrotic scarring. Polycaprolactone (PCL) fibers with or without dexamethasone were electrospun onto the ETT surface PCL-only coated ETTs and placed in native airways of 18 Yorkshire swine. Regular and dexamethasone-PCL coated ETTs were placed in airways of another 18 swine injured by inner laryngeal mucosal abrasion. All groups were evaluated after 3, 7 and 14 days (n = 3/treatment/time). Larynges were bisected and localized stiffness determined by normal indentation, then sequentially matched with histological assessment. In the native airway, tissue stiffness with PCL-only ETT placement increased significantly from 3 to 7 days (p = 0.0016) and 3 to 14 days (p < 0.0001) while dexamethasone-PCL ETT placement resulted in stiffness decreasing from 7 to 14 days (p = 0.031). In the injured airway, localized stiffness at 14 days was significantly greater after regular ETT placement (23.1 ± 0.725 N/m) versus dexamethasone-PCL ETTs (17.10 ± 0.930 N/m, p < 0.0001). Dexamethasone-loaded ETTs were found to reduce laryngotracheal tissue stiffening after simulated intubation injury compared to regular ETTs, supported by a trend of reduced collagen in the basement membrane in injured swine over time. Findings suggest localized corticosteroid delivery allows for tissue stiffness control and potential use as an approach for prevention and treatment of scarring caused by intubation injury.

Changes in vocal fold gene expression and histology after injection augmentation in a recurrent laryngeal nerve injury model.

OBJECTIVE: To investigate changes in neuroregenerative pathways with vocal fold denervation in response to vocal fold augmentation. METHODS: Eighteen Yorkshire crossbreed swine underwent left recurrent laryngeal nerve transection, followed by observation or augmentation with carboxymethylcellulose or calcium hydroxyapatite at two weeks. Polymerase chain reaction expression of genes regulating muscle growth (MyoD1, MyoG and FoxO1) and atrophy (FBXO32) were analysed at 4 and 12 weeks post-injection. Thyroarytenoid neuromuscular junction density was quantified using immunohistochemistry. RESULTS: Denervated vocal folds demonstrated reduced expression of MyoD1, MyoG, FoxO1 and FBXO32, but overexpression after augmentation. Healthy vocal folds showed increased early and late MyoD1, MyoG, FoxO1 and FBXO32 expression in all animals. Neuromuscular junction density had a slower decline in augmented compared to untreated denervated vocal folds, and was significantly reduced in healthy vocal folds contralateral to augmentation. CONCLUSION: Injection augmentation may slow neuromuscular degeneration pathways in denervated vocal folds and reduce compensatory remodelling in contralateral healthy vocal folds.

Quantifying Intubation Forces on Incisors and Tongue Base Across Exposure Difficulty and Experience in a Simulator.

OBJECTIVE: Laryngoscopy simulators quantifying forces on critical structures in progressively challenging airways and operator expertise are lacking. We aimed to quantify laryngoscopy forces across expertise and exposure difficulty. STUDY DESIGN: Prospective observational study Setting: Tertiary care medical center Methods: Force gauges were affixed to a difficult airway mannequin to quantify teeth and tongue forces across increasingly challenging airway exposure. Medical students (n=10), residents (n=11), and otolaryngology staff (n=10) performed direct laryngoscopy using a Miller size 3 laryngoscope with 1) normal neck/jaw mobility, 2) restricted neck extension, 3) restricted jaw opening, and 4) restricted neck/jaw mobility. Incisor and tongue pounds of force (lbf) were continuously measured. RESULTS: As the difficulty setting increased, forces exerted by the students, residents, and staff on the incisors and tongue base increased (p=0.01). Between normal and maximally restricted settings, force delivered to the incisors increased by 6.95 lbf (standard error (SE) 1.29), 5.93 lbf (SE 0.98), and 5.94 lbf (SE 0.70) for the students, residents, and staff, respectively. At the tongue base, force increased by 0.37 lbf (SE 0.18), 0.46 lbf (SE 0.14), and 0.73 lbf (SE 0.15) for the students, residents, and staff, respectively. Esophageal intubations occurred in 50% of the students, 23% of the residents, and 45% of the otolaryngology staff at maximal difficulty, with none at the easiest setting (p=0.33). Compared to the residents, the staff applied significantly increased pressure on the tongue base during laryngoscopy (p=0.02). CONCLUSION: Forces exerted on the incisors and tongue base varied across exposure difficulty and expertise levels, suggesting that they may be useful markers for training and competence assessment.

Effect of continuous local dexamethasone on tissue biomechanics and histology after inhalational burn in a preclinical model.

Objective: Inhalational burns frequently lead to dysphonia and airway stenosis. We hypothesize local dexamethasone delivery via a novel drug-eluting electrospun polymer-mesh endotracheal tube (ETT) reduces biomechanical and histologic changes in the vocal folds in inhalational burn. Methods: Dexamethasone-loaded polymer mesh was electrospun onto ETTs trimmed to transglottic endolaryngeal segments and secured in nine Yorkshire Crossbreed swine with directed 150°C inhalation burns. Uncoated ETTs were implanted in nine additional swine with identical burns. ETT segments were maintained for 3 and 7 days. Vocal fold (VF) structural stiffness was measured using automated-indentation mapping and compared across groups and to four uninjured controls, and matched histologic assessment performed. Statistical analysis was conducted using two-way ANOVA with Tukey's post hoc test and Wilcoxon rank-sum test. Results: VF stiffness after burn decreased with longer intubation, from 19.4 (7.6) mN/mm at 3 days to 11.3 (5.2) mN/mm at 7 days (p < .0001). Stiffness similarly decreased with local dexamethasone, from 25.9 (17.2) mN/mm at 3 days to 18.1 (13.0) mN/mm at 7 days (p < .0001). VF stiffness in the dexamethasone group was increased compared to tissues without local dexamethasone (p = .0002), and all groups with ETT placement had higher tissue stiffness at 3 days (p < .001). No significant change in histologic evidence of epithelial ulceration or fibrosis was noted, while an increased degree of inflammation was noted in the dexamethasone group (p = .04). Conclusion: Local dexamethasone delivery increases VF stiffness and degree of inflammation compared to uncoated ETTs in an acute laryngeal burn model, reflected in early biomechanical and histologic changes in an inhalational burn model.

The Case Against Stapedectomy as a Core Competency for General Practice: A Study of Care Patterns in the Department of Defense.

OBJECTIVE: Stapedectomy remains a key indicator case reportable to the Accreditation Council of Graduate Medical Education despite the decline in the incidence of otosclerosis over the last half century. This study compared the rates of stapedectomy performed by otolaryngologists at academic and nonacademic centers. STUDY DESIGN: Retrospective review. SETTING: Tertiary referral academic centers, nonacademic centers, and civilian purchased-care across the Department of Defense between 2015 and 2020. PATIENTS: Department of Defense beneficiaries with otosclerosis near a military treatment facility with an otolaryngologist. INTERVENTIONS: Stapedectomy (Current Procedural Terminology codes 69,660, 69,661, and 69,662). MAIN OUTCOME MEASURES: Number of stapedectomies performed by setting. RESULTS: From 2015 to 2020, 426 stapedectomies were performed at or near a military treatment facility with an otolaryngologist (274 directly by military otolaryngologists, 152 by community providers). Military providers performed 94% of stapedectomies at or near military academic centers, versus only 30% at or near nonacademic centers ( p < 0.0001). Among the 60 stapedectomies performed at nonacademic centers, only 30 were performed by general otolaryngologists (7% of all stapedectomies performed; 11% of procedures by military providers) while the rest were performed by fellowship-trained otologist or neurotologist. CONCLUSIONS: Low stapes surgical volume by military general otolaryngologists reinforces recent epidemiologic trends and suggests that few general otolaryngologists graduate residency with sufficient competency to pursue independently performing stapedectomy or have difficulty maintaining competency after graduation.

Augmentation and vocal fold biomechanics in a recurrent laryngeal nerve injury model.

Objectives/hypothesis: Composite vocal fold (VF) biomechanical data are lacking for augmentation after recurrent laryngeal nerve (RLN) injury. We hypothesize resulting atrophy decreases VF stiffness and augmentation restores native VF biomechanics. Methods: Sixteen Yorkshire Crossbreed swine underwent left RLN transection and were observed or underwent carboxymethylcellulose (CMC) or calcium hydroxyapatite (CaHa) augmentation at 2 weeks. Biomechanical measurements (structural stiffness, displacement, and maximum load) were measured at 4 or 12 weeks. Thyroarytenoid (TA) muscle cross-sectional area was quantified and compared with two-way ANOVA with Tukey's post hoc test. Results: After 4 weeks, right greater than left structural stiffness (mean ± SE) was observed (49.6 ± 0.003 vs. 28.4 ± 0.002 mN/mm), left greater than right displacement at 6.3 mN (0.54 ± 0.01 vs. 0.46 ± 0.01 mm, p < .01) was identified, and right greater than left maximum load (72.3 ± 0.005 vs. 40.8 ± 0.003 mN) was recorded. TA muscle atrophy in the injured group without augmentations was significant compared to the noninjured side, and muscle atrophy was seen at overall muscle area and individual muscle bundles. CMC augmentation appears to maintain TA muscle structure in the first 4 weeks with atrophy present at 12 weeks. Conclusions: VF biomechanical properties match TA muscle atrophy in this model, and both CMC and CaHa injection demonstrated improved biomechanical properties and slower TA atrophy compared to the uninjured side. Taken together, these data provide a quantifiable biomechanical basis for early injection laryngoplasty to improve dysphonia and potentially improve healing in reversible unilateral vocal fold atrophy. Level of evidence: N/A.

Asynchronous learning among otolaryngology residents in the United States.

OBJECTIVE: Otolaryngology resident learning has historically relied on didactic lectures, textbook reading, and practical hands-on patient care. However, evidence suggests that an increasing proportion of residents in other specialties are deviating from this paradigm. This work aims to characterize otolaryngology residents' current asynchronous learning practices (i.e., personal learning outside of didactics and patient care). METHODS: A thirteen-question survey of otolaryngology residents in the United States was performed from 10/1/2020-12/1/2020 assessing demographics, educational resource utilization, and educational resource preference. RESULTS: Nearly all (99 %) respondents reported engaging with educational materials outside of didactics and case prep. Textbook reading comprised 27 % of residents' total study time, with additional time split between board-review book reading (20 %), searching the web (18 %), watching online videos (15 %), and listening to podcasts (10 %). Residents' highest ranked resources were videos, board-review books, textbooks, podcasts, and recorded lectures. Among electronic and multimedia resources, more than half of residents used the following resources: Iowa Head and Neck Protocols (91 %), Board Vitals (75 %), UpToDate (60 %), YouTube (57 %), Google (56 %), and Headmirror (54 %). CONCLUSION: Current otolaryngology resident learning involves substantial use of asynchronous learning, including videos, web-based learning, and podcasts, which currently outpace traditional textbook- and didactic-based education. This underscores the need to consider a paradigm shift within academic otolaryngology education away from textbooks and other tradition media to the generation of high-quality multimedia resources for resident learning.

Three-Dimensional Technology in Rhinoplasty.

Rhinoplasty is uniquely suited to capitalize on different aspects of three-dimensional (3D) modeling technology. Currently, 3D surface imaging of preoperative and postoperative nasal structure provides a platform for better surgical planning and patient counselling as well as objective postoperative measurements. Physical nasal models using 3D printing technology can improve rhinoplasty performance intraoperatively, postoperative outcomes, together with nasal prosthetic manufacture, by tailoring to specific patient anatomy. Advances in tissue engineering using 3D-printed biocompatible scaffolds have shown excellent nasal cartilage mimicry and hold promise for increasingly versatile directed tissue regeneration in rhinoplasty and nasal reconstructive surgery. As health care innovations are expected to become increasingly common in standard rhinoplasty practices in the future, we give an account of how 3D technologies can create new opportunities to optimize surgical planning and improve overall the patient experience.

Releasing the Smile: Depressor Anguli Oris Excision in the Context of Managing Nonflaccid Facial Palsy.

BACKGROUND: Nonflaccid facial palsy is a debilitating entity characterized by hypertonicity, synkinesis, and hypomobility. Patients with nonflaccid facial palsy often have smile asymmetry and restriction because of disruption of normal vector forces on the modiolus. Excision of the depressor anguli oris can lead to improved oral commissure excursion, smile angle, dental show, and symmetry. METHODS: All depressor anguli oris resection cases between January 8, 2018, and December 26, 2019, were reviewed. Patients with postoperative photographs were included in this cohort study. Preoperative and postoperative photographs were analyzed using the Emotrics software program, and changes in oral commissure excursion, smile angle, and dental show were tracked. Clinician-graded facial palsy assessments and patient-reported outcome measures were compared preoperatively and postoperatively using the Electronic Facial Paralysis Assessment and Facial Clinimetric Evaluation Scale, respectively. RESULTS: Forty-three patients were included in this study; 79 percent of patients underwent isolated depressor anguli oris resection. Depressor anguli oris resection led to a statistically significant increase in oral commissure median excursion, smile angle, and dental show [3.02 mm (p = 0.015), 1.70 degrees (p = 0.002), and 2.36 mm (p < 0.001), respectively]. Median Electronic Facial Paralysis Assessment and Facial Clinimetric Evaluation Scale instrument scores also improved [6.0 (p = 0.001) and 7.5 (p = 0.013), respectively]. Depressor anguli oris resection also led to more symmetric smiles. No correlation was seen between duration of follow-up and change in metrics. CONCLUSION: Depressor anguli oris resection is a minimal-risk procedure that frequently results in improved smile dynamics, smile symmetry, and quality of life in patients with nonflaccid facial palsy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Determining the Prognosis of Bell's Palsy Based on Severity at Presentation and Electroneuronography.

OBJECTIVE: To examine the demographics of Bell's palsy and determine how House-Brackmann (HB) grade at nadir and electroneuronography (ENoG) results correlate with HB grade after recovery and development of synkinesis. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care military medical center. METHODS: Patients with acute Bell's palsy and adequate follow-up, defined as 6 months or return to HB grade I function, were included. Demographic information, HB scores at nadir and recovery, and ENoG results were collected. RESULTS: A total of 112 patient records were analyzed. Ages ranged from 8 to 87 years with peaks at 21 to 25 and 61 to 65 years. Among patients, 16.3% reached a nadir at HB II, 41.9% at HB III, 5.4% at HB IV, 16.3% at HB V, and 20.1% at HB VI. The overall recovery rate was 73.2% to HB I function, 17.0% to HB II, and 9.8% to HB III. The chance of recovery to HB I decreased as the severity of paralysis increased (rs = -1.0, P < .0001). Mean time to recovery to HB I was 6 weeks. Greater degeneration on ENoG suggested worse recovery (rs = 0.62, P = .01). Patients with HB V and VI were most likely to develop synkinesis. CONCLUSION: More severe paralysis increased the chance of recovery to HB II or III function. The granularity of this study provides prognostic insights that may inform the counseling of patients with Bell's palsy with respect to prognosis and recovery timeline.

Podcast-Based Learning in Otolaryngology: Availability, Breadth, and Comparison with Other Specialties.

OBJECTIVES/HYPOTHESIS: Studies across multiple specialties of medical students, residents, and attending physicians demonstrate increased retention, breadth of knowledge, and literature awareness when podcasts are used as an adjunctive educational tool. This Contemporary Review aims to 1) quantify podcast availability and episode frequency for medical learners across a broad range of specialties, and 2) compare these metrics between otolaryngology-specific podcasts with those of other specialties. DATA SOURCES: Top five podcast platforms: Spotify (Stockholm, Sweden 2006), Apple Podcasts (Cupertino, CA 2012), Google Podcasts (Mountain View, CA 2018), Stitcher (San Francisco, CA 2008), and TuneIn (San Francisco, CA 2002). METHODS: The selected podcast platforms were queried with a comprehensive set of keywords and manually searched for medically-relevant podcasts. Specialty, content, and number of episodes annually for the last 10 years were recorded for each podcast. RESULTS: Otolaryngology has a comparable number of podcasts and breakdown of podcast category compared to other specialties, but reduced total episodes and episode frequency compared to other specialties. This may limit otolaryngologists' ability to engage in this validated form of medical education. CONCLUSIONS: Podcast-based education provides a valuable resource for medical professionals to reinforce learning, broaden general knowledge base, and stay updated on current literature, particularly in light of increased demand for mobile and on-demand learning options. There is room for an increased number of podcasts and, particularly, increased episode frequency within the field of otolaryngology to extend these benefits to otolaryngologists and otolaryngologists in training. Laryngoscope, 131:E2131-E2138, 2021.

Reliability Between In-Person and Still Photograph Assessment of Facial Function in Facial Paralysis Using the eFACE Facial Grading System.

Importance: Assessing facial function using high-quality photographs would improve long-term and objective outcomes tracking in facial palsy, facilitate automated facial grading using artificial intelligence algorithms, and allow for remote follow up. Objective: To determine agreement between in-person and photographic electronic facial function scale (eFACE) assessments, and evaluate inter-rater reliability of photographic eFACE evaluation. Design, Setting, and Participants: Retrospective review of eFACE scores from in-person interviews and standardized photographs using the Massachusetts Eye and Ear (MEE) Standard Facial Palsy Dataset. Main Outcomes and Measures: eFACE total scores and subset scores determined by two experienced facial reanimation surgeons in person and from photographs. Results: Intraclass correlation coefficients for eFACE scores were 0.96 (95% CI 0.94 to 0.97) for total scores, 0.99 (95% CI 0.989 to 0.995) for static scores, 0.82 (95% CI 0.74 to 0.88) for dynamic scores, and 0.98 (95% CI 0.97 to 0.99) for synkinesis scores. Photographic and in-person scores had a mean difference of -0.64 (95% CI -2.05 to 0.77; p = 0.37) for total score, -1.58 (95% CI -4.22 to 1.05; p = 0.24) for the static subset, 0.14 (95% CI -1.70 to 1.97; p = 0.88) for the dynamic subset, and -1.11 (95% CI -3.09 to 0.86; p = 0.26) for the synkinetic subset. Bland-Altman analysis showed no trend for increasing differences in total score or subset scores. Conclusions: eFACE assessment obtained via photographs exhibits excellent inter-rater reliability and strong agreement with in-person assessment, demonstrating facial symmetry in facial palsy patients can be monitored using standardized frontal photographs.

Implantable wireless device for study of entrapment neuropathy.

BACKGROUND: Disease processes causing increased neural compartment pressure may induce transient or permanent neural dysfunction. Surgical decompression can prevent and reverse such nerve damage. Owing to insufficient evidence from controlled studies, the efficacy and optimal timing of decompression surgery remains poorly characterized for several entrapment syndromes. NEW METHOD: We describe the design, manufacture, and validation of a device for study of entrapment neuropathy in a small animal model. This device applies graded extrinsic pressure to a peripheral nerve and wirelessly transmits applied pressure levels in real-time. We implanted the device in rats applying low (under 100 mmHg), intermediate (200-300 mmHg) and high (above 300 mmHg) pressures to induce entrapment neuropathy of the facial nerve to mimic Bell's palsy. Facial nerve function was quantitatively assessed by tracking whisker displacements before, during, and after compression. RESULTS: At low pressure, no functional loss was observed. At intermediate pressure, partial functional loss developed with return of normal function several days after decompression. High pressure demonstrated complete functional loss with incomplete recovery following decompression. Histology demonstrated uninjured, Sunderland grade III, and Sunderland grade V injury in nerves exposed to low, medium, and high pressure, respectively. COMPARISON WITH EXISTING METHODS: Existing animal models of entrapment neuropathy are limited by inability to measure and titrate applied pressure over time. CONCLUSIONS: Described is a miniaturized, wireless, fully implantable device for study of entrapment neuropathy in a murine model, which may be broadly employed to induce various degrees of neural dysfunction and functional recovery in live animal models.

Effect of Weakening of Ipsilateral Depressor Anguli Oris on Smile Symmetry in Postparalysis Facial Palsy.

IMPORTANCE: Aberrant depressor anguli oris (DAO) activity may arise after recovery from acute facial paralysis and restrict movement of the oral commissure. OBJECTIVE: To quantify the degree to which DAO inhibition affects smile dynamics and perceived emotional state. DESIGN, SETTING, AND PARTICIPANTS: In this prospective, pretest-posttest study performed at an academic tertiary referral hospital, patients with unilateral postparalysis facial palsy were studied from January 16 through April 30, 2016. INTERVENTIONS: Local anesthetic injection into the ipsilateral DAO. MAIN OUTCOMES AND MEASURES: Healthy- and paretic-side commissure displacements from the midline lower vermillion border referenced to the horizontal plane were calculated from random-ordered photographs of full-effort smile before and after injection, and random-ordered hemifacial photographs of the paretic side were assessed as expressing positive, negative, or indiscernible emotion. RESULTS: Twenty patients were identified as having unilateral postparalysis facial palsy with marked synkinesis of the ipsilateral DAO. Patient mean age was 46 years (range, 24-67 years), with a male to female ratio of 1:3. Mean paretic-side commissure displacement increased from 27.45 mm at 21.65° above the horizontal plane to 29.35 mm at 23.58° after DAO weakening (mean difference, 1.90 mm; 95% CI, 1.26-2.54 mm; and 1.93°; 95% CI, 0.34°-3.51°; P < .001 and P = .20, respectively). Symmetry of excursion between sides improved by 2.00 mm (95% CI, 1.16-2.83 mm; P < .001) and 2.71° (95% CI, 1.38°-4.03°; P < .001). At baseline, observers assessed 7 of 20 paretic hemifaces (35%) as expressing positive emotion; this proportion increased to 13 of 20 (65%) after DAO weakening (P = .03). CONCLUSIONS AND RELEVANCE: Ipsilateral DAO weakening results in significant improvements in smile dynamics and perceived expression of positive emotion on the paretic hemiface in postparalysis facial palsy. A trial of DAO weakening should be offered to patients with this disfiguring complication of Bell palsy and similar facial nerve insults. LEVEL OF EVIDENCE: 3.