Persistence of lower vocal intensity in vocal fold paralysis with cricothyroid impairment after hyaluronate injection.

Background: Unilateral vocal fold paralysis (UVFP) affects the glottal gap, voice, and aerodynamics, whereas injection laryngoplasty (IL) using hyaluronate is an effective treatment for UVFP by decreasing the glottal gap to improve voice. Previous studies have shown that the involvement of cricothyroid (CT) muscle in UVFP patients further affects patients' aerodynamics, but it remains unclear whether the difference remains after IL. This study investigates whether the aerodynamic features observed in UVFP with CT involvement could still be observed after IL. Methods: This study recruited UVFP patients with dysphonia, and IL was performed within 6 months of initial symptoms. All subjects received assessments including videolaryngoscopy, voice analysis, and aerodynamics at three time points: before IL, 1 month after IL, and 6 months after IL. The glottal gap, voice, and aerodynamics between patients with and without CT involvement (the CT+ and CT- groups) were compared, and the change (Δ) before and after IL and repeated-measures analysis of variance (ANOVA) were also compared between the two groups. Result: A total of 71 patients with UVFP (22 in the CT+ group and 49 in the CT- group) were analyzed. After IL, the CT+ group showed a lower sound pressure level (SPL), higher Δair pressure, and smaller Δaerodynamic power than the CT- group. Conclusion: The CT+ group had a lower SPL, even after elevating air pressure to attempt to achieve a higher vocal intensity. The results suggest that although closure of the glottal gap was achieved by IL, the CT+ group still had a lower loudness and needed to sustain a higher peak air pressure when producing voice. Level of evidence: Level 4.

Aerodynamic Performance and Neuromuscular Control in Patients with Unilateral Vocal Fold Paralysis.

Unilateral vocal fold paralysis (UVFP) causes glottal incompetence and poor vocal efficiency. The influence of laryngeal neuromuscular control on aerodynamics in UVFP remains unclear. This study investigated the relationship between laryngeal muscle activities using quantitative laryngeal electromyography (LEMG) and aerodynamics in UVFP. This prospective study recruited patients with UVFP, and the diagnosis was confirmed with videolaryngostroboscopy and LEMG. The patient received aerodynamic assessment and LEMG of the thyroarytenoid-lateral cricoarytenoid (TA-LCA) muscle complex and the cricothyroid (CT) muscle. The relationship between quantitative LEMG and aerodynamic parameters was analyzed. A total of 134 UVFP patients without concurrent CT muscle involvement were enrolled. Compared with the normal side, the peak turn frequency of the lesioned side was lower in the TA-LCA (p < 0.001) and CT (p = 0.048) muscles. Stepwise linear regression revealed that the turn ratio of TA-LCA muscles was a robust factor in the decrease in peak expiratory airflow (ß = −0.34, p = 0.036), mean airflow during voicing (ß = −0.28, p = 0.014), and aerodynamic power (ß = −0.42, p = 0.019), and an increase in aerodynamic efficiency (ß = 27.91, p = 0.012). In addition, the turn ratio of CT muscles was a potent factor in inducing an increase in aerodynamic resistance (ß = 14.93, p = 0.029). UVFP without CT involvement still showed suppression of CT muscles on the lesioned side, suggesting that neurological impairment of the TA-LCA complex could cause asymmetrical compensation of CT muscles, further impeding aerodynamics. The residual function of TA-LCA muscle complexes facilitates less air leakage and power dissipation, enhancing aerodynamic efficiency. On the other hand, the symmetrical compensation of the CT muscles improves aerodynamic resistance.

Cricothyroid Dysfunction in Unilateral Vocal Fold Paralysis Females Impairs Lexical Tone Production.

In this cross-sectional study, we compared voice tone and activities relating to the laryngeal muscle between unilateral vocal fold paralysis (UVFP) patients with and without cricothyroid (CT) muscle dysfunction to define how CT dysfunction affects language tone. Eighty-eight female surgery-related UVFP patients were recruited and received acoustic voice analysis and laryngeal electromyography (LEMG) when the patient was producing the four Mandarin tones. The statistical analysis was compared between UVFP patients with (CT+ group, 17 patients) and without CT muscle (CT- group, 71 patients) involvement. When producing Mandarin Tone 2, the voice tone in the CT+ group had smaller rise range (p = 0.007), lower rise rate (p = 0.002), and lower fundamental frequency (F0) at the offset point of the voice (p = 0.023). When producing Mandarin Tone 4, the voice tone in the CT+ group had smaller drop range (p = 0.019), lower drop rate (p = 0.005), and lower F0 at voice onset (p = 0.025). The CT+ group had significantly lower CT muscle activity when producing the four Mandarin tones. In conclusion, CT dysfunction causes a limitation of high-rising tone in Tone 2 and high-falling tone in Tone 4, a property that dramatically limits the tonal characteristics in Mandarin, a tonal language. This limitation could further impair the patient's communication ability.

Speech Performance after Anterolateral Thigh Phonatory Tube Reconstruction for Total Laryngectomy.

OBJECTIVE: Traditionally, after total laryngopharyngectomy (TLP), patients cannot speak without a prosthesis or an artificial larynx. In Taiwan, most patients use a commercialized pneumatic laryngeal device (PLD). Phonatory tube reconstruction with the anterolateral thigh (ALT) flap is a novel, modified version of synchronous digestive and phonatory reconstruction involving a free muscular cutaneous flap. This study reviewed and compared speech performance between patients who underwent novel flap reconstruction and conventional PLD users. METHOD: We retrospectively reviewed patients with laryngeal or hypopharyngeal cancer who underwent TLP from August 2017 to September 2019. The voice handicap index (VHI), speech intelligibility, acoustic and aerodynamic analysis results, and speech range profile (SRP) were compared between patients who underwent ALT phonatory tube reconstruction (ALT group) and those using PLDs (PLD group). RESULTS: Twenty patients were included; 13 patients were included in the ALT group, and 7 patients were included in the PLD group. Compared to the PLD group, the ALT group had a better fundamental frequency range (P < .001) and semitone range (P < .001) during speech but showed worse jitter, shimmer, and harmonic-to-noise ratios. The two groups showed comparable VHI and speech intelligibility performance. CONCLUSIONS: The ALT phonatory tube, a novel flap for reconstruction, can restore digestive and voice functions simultaneously. Compared with PLD use, ALT phonatory tube reconstruction yields an improved speech range and comparable levels of voice handicap and speech intelligibility, suggesting that the technique is a good alternative for patients after TLP. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:1349-1357, 2021.

Two trajectories of functional recovery in thyroid surgery related unilateral vocal cord paralysis.

BACKGROUND: Iatrogenic unilateral vocal fold paralysis caused by thyroid surgery induces profound physical and psychosocial distress in patients. The natural course of functional recovery over time differs substantially across subjects, but the mechanisms underlying this difference remain unclear. In this study, we examined whether the anatomic site of the lesion affected the trajectory of recovery. METHODS: In this prospective case series study in a single medical center, patients with thyroid surgery-related unilateral vocal fold paralysis were evaluated using quantitative laryngeal electromyography, videolaryngostroboscopy, voice acoustic analysis, the Voice Outcome Survey, and the Short Form-36 quality-of-life questionnaire. Patients with and without superior laryngeal nerve injuries were compared. RESULTS: Forty-two patients were recruited, among whom 15 and 27 were assigned to the with and without superior laryngeal nerve injury groups, respectively. Compared with the group without superior laryngeal nerve injury, the group with superior laryngeal nerve injury group demonstrated less improvement in the recruitment of vocal fold adductors, and the group also had more severe impairment of vocal fold vibration, maximum phonation time, jitter, shimmer, and harmony-to-noise ratio at the first evaluation. This difference was also found in the glottal gap and maximum phonation time 12 months after the injury. CONCLUSION: Among patients with thyroid surgery-related unilateral vocal fold paralysis, superior laryngeal nerve injury induces a distinctively different recovery trajectory compared with those without superior laryngeal nerve injury characterized by less reinnervation of vocal fold adductors and worse presentation in terms of the glottal gap and maximum phonation time. This study emphasizes the importance of superior laryngeal nerve function and its preservation in thyroid surgery.

The impact of cricothyroid involvement on adductor recovery in unilateral vocal fold paralysis.

OBJECTIVES/HYPOTHESIS: Wide variation in postinjury functional recovery is a hallmark of unilateral vocal fold paralysis (UVFP), ranging from zero to full recovery. The present study examined the impact of cricothyroid (CT) muscle involvement on recovery using quantitative laryngeal electromyography (LEMG) of the thyroarytenoid-lateral cricoarytenoid (TA-LCA) muscle complex at multiple times postinjury. STUDY DESIGN: Prospective cohort study in a medical center. METHODS: Eighty-one patients with UVFP (37 males and 44 females) received an initial assessment of quantitative LEMG, stroboscope, acoustic voice analysis and 36-Item Short Form Survey quality-of-life questionnaire at 3 to 6 months after UVFP onset and a follow-up assessment at 12 months after UVFP onset. RESULTS: The initial and follow-up assessments were performed at 4.3 ± 1.9 and 12.5 ± 1.3 months after UVFP onset, respectively. The peak turn frequency of the TA-LCA muscle complex on the lesion side was improved at the follow-up (470 ± 294 Hz) compared with the initial assessment (300 ± 204 Hz) (P < .001). Patients were also divided into two groups with (n = 27) and without (n = 54) CT involvement, respectively. TA-LCA muscle complex turn frequency improved in patients without CT involvement (from 277 ± 198 to 511 ± 301 Hz; P < .001), but not in those with CT involvement (from 345 ± 211 to 386 ± 265 Hz; P = .46). Seventy-one of all patients received early intervention with intracordal hyaluronate injection, showing similar therapeutic effects in those with and without CT involvement. CONCLUSIONS: Acute UVFP with combined TA-LCA muscle complex and CT muscle involvement has a poor prognosis, with poorer recovery of TA-LCA muscle complex recruitment. Early interventions should be considered in patients with UVFP with CT involvement. LEVEL OF EVIDENCE: 2 Laryngoscope, 130:139-145, 2020.

Voice aerodynamics following office-based hyaluronate injection laryngoplasty.

OBJECTIVES: Neuromuscular control, glottal conformation and aerodynamics are the major factors affecting voice performance. We aimed to characterise the degree to which voice improvements following office-based intracordal hyaluronate injection laryngoplasty (HIL) depend on changes in voice aerodynamics in patients with unilateral vocal fold paralysis (UVFP), by assessing the correlations between these parameters. DESIGN: Prospective case series. SETTING: Otolaryngology Clinics in a Medical Center. PARTICIPANTS: Patients with UVFP within 6 months of their first outpatient visit who received single HIL. MAIN OUTCOME MEASURES: Videolaryngostroboscopy, aerodynamics and laboratory voice analysis were evaluated at baseline and 1 month after HIL. Quantitative laryngeal electromyography was evaluated at baseline to confirm UVFP. RESULTS: Seventy-five newly diagnosed patients with UVFP were analysed. The normalised glottal gap area (NGGA) decreased (P < 0.001) (Cohen's dz  = 0.94) and all aerodynamic parameters improved (all P < 0.05) (Cohen's dz  = 0.38-1.02) following HIL. Patients undergoing thoracic surgery had more profound aerodynamic impairments both before and after HIL. After adjusting for improvements in NGGA, the improvement in aerodynamics was correlated with voice improvement and most notably with maximum phonation time and jitter/shimmer. CONCLUSIONS: Hyaluronate injection laryngoplasty improved glottal conformation, aerodynamics and voice, highlighting the benefit of early HIL intervention for patients with UVFP. Patients with UVFP caused by thoracic surgery continued to have poorer aerodynamics post-HIL, indicating the importance of speech therapy in these patients.

Voice Range Change After Injection Laryngoplasty for Unilateral Vocal Fold Paralysis.

OBJECTIVES: Patients with unilateral vocal fold paralysis (UVFP) caused by nerve injury manifest with voice changes. This study investigated vocal performance measured by voice range profile (VRP) in patients with UVFP and changes in VRP in response to intracordal hyaluronate injection. METHODS: Eighty-five patients with UVFP were enrolled prospectively, among whom 68 received intracordal hyaluronate injections. The outcome measurements included VRP, acoustic and aerodynamic analyses, peak turn frequency of thyroarytenoid-lateral cricoarytenoid muscle complex (TA-LCA) measured by laryngeal electromyography, and normalized glottal gap area by videolaryngostroboscopy. RESULTS: The peak turn frequency of the paralyzed TA-LCA showed a modest correlation with max fundamental frequency (F0) and F0 range. Closed-phase normalized glottal gap area showed modest negative correlations with max F0 and F0 semitone range. Regarding conventional acoustic and aerodynamic analyses, the paralyzed TA-LCA peak turn frequency was only correlated with maximal phonation time. Intracordal hyaluronate injection improved VRP performance by increasing max F0, decreasing min F0, increasing F0 range, and increasing semitone range (all P <0.01) with small or medium strength of effect size (Cohen d, 0.39-0.76). CONCLUSIONS: Change in voice pitch in patients with UVFP can partly predict impairment of neuromuscular functions and glottal gap. VRP provides a more sensitive reflection of the severity of neuromuscular impairment, compared with conventional voice analysis. The validity of VRP is further supported by a robust response to voice improvements following injection laryngoplasty.

Implications of Synkinesis in Unilateral Vocal Fold Paralysis.

Objectives In patients with unilateral vocal fold paralysis (UVFP), laryngeal electromyography (LEMG) occasionally observes synkinesis in laryngeal muscles, a condition that could impair vocal fold mobility and voice control. This study aims to evaluate the impact of synkinesis on UVFP patients. Study Design A retrospective case-control study. Setting Medical center. Subjects and Methods Patients with UVFP onset >6 months were recruited (N = 104). The outcome measurements included LEMG, quantitative LEMG analysis of thyroarytenoid-lateral cricoarytenoid (TA-LCA) muscle complex, glottal gap measured by videolaryngostroboscopy, voice-related quality of life, and voice acoustic analysis. Results According to the LEMG analysis, 8 patients (8%) had synkinesis, and 96 (92%) did not. In the synkinesis group, TA-LCA turn frequency in the lesioned side was comparable to that in the healthy side ( P = .52). Patients in the synkinesis group had higher TA-LCA turn frequency ( P = .001), higher probability of cricothyroid muscle dysfunction ( P = .04), and better voice-related quality of life ( P = .01) but objective voice outcomes comparable to those in the nonsynkinesis group. Conclusions Patients with synkinesis will have near-complete restoration in TA-LCA turn frequency but still experience voice impairment, a finding that is compatible with the mechanism of aberrant reinnervation. However, patients with synkinesis have better disease-related quality of life than do those without synkinesis.

Life quality improvement in hoarse patients with early glottic cancer after transoral laser microsurgery.

BACKGROUND: The purpose of this study was to evaluate the recovery kinetics of voice and quality of life (QOL) over time in patients with early glottic cancer who underwent transoral laser microsurgery (TLM). METHODS: A prospective cohort study was conducted in which acoustic and aerodynamic voice assessments and QOL analyses were done using health-related questionnaires (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30-questions [EORTC-QLQ-C30] and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Head and Neck 35-questions [EORTC-QLQ-H&N35]) were administered at designated times. RESULTS: Most voice laboratory parameters worsened during the first month, then recovered to baseline after 6 months. The QLQ-H&N35 speech subscale was significantly improved. Among the voice laboratory parameters, pretreatment harmonics-to-noise ratio was an independent predictor (P = .041) for improvement on the speech subscale at the endpoint. CONCLUSION: Despite an initial deterioration of voice and QOL in the first month, patients who underwent TLM recovered to a plateau since the sixth month and then to better than preoperative status afterward. A greater improvement in QOL was seen in patients with poorer baseline voice quality.

Speech intelligibility, speaking rate, and vowel formant characteristics in Mandarin-speaking children with cochlear implant.

The effects of the use of cochlear implant (CI) on speech intelligibility, speaking rate, and vowel formant characteristics and the relationships between speech intelligibility, speaking rate, and vowel formant characteristics for children are clinically important. The purposes of this study were to report on the comparisons for speaking rate and vowel space area, and their relationship with speech intelligibility, between 24 Mandarin-speaking children with CI and 24 age-sex-education level matched normal hearing (NH) controls. Participants were audio recorded as they read a designed Mandarin intelligibility test, repeated prolongation of each of the three point vowels /i/, /a/, and /u/ five times, and repeated each of three sentences carrying one point vowel five times. Compared to the NH group, the CI group exhibited: (1) mild-to-moderate speech intelligibility impairment; (2) significantly reduced speaking rate mainly due to significantly longer inter-word pauses and larger pause proportion; and (3) significantly less vowel reduction in the horizontal dimension in sustained vowel phonation. The limitations of speech intelligibility development in children after cochlear implantation were related to atypical patterns and to a smaller degree in vowel reduction and slower speaking rate resulting from less efficient articulatory movement transition.

Outcomes of fat injection laryngoplasty in unilateral vocal cord paralysis.

OBJECTIVE: To analyze outcomes following fat injection laryngoplasty in patients with unilateral vocal cord paralysis. DESIGN: Longitudinal outcomes evaluation study. SETTING: Tertiary referral voice center. PATIENTS: Thirty-three consecutive patients with unilateral vocal cord paralysis undergoing autologous fat injection laryngoplasty with preoperative and serial postoperative follow-up at Chang Gung Memorial Hospital, Taipei, Taiwan. INTERVENTION: Autologous fat injection laryngoplasty. MAIN OUTCOME MEASURES: Voice laboratory measurements, Voice Outcome Survey, and 36-item Short Form Health Survey. RESULTS: Except for the physical functioning dimension of global health, voice-related subjective outcomes and acoustic variables of the patients significantly improved after surgery (P < .05). Compared with population norms, the mean (SD) scores of patients were inferior on the 36-item Short Form Health Survey dimensions of physical functioning (80.7 [22.3] vs 90.2 [17.4]) and role functioning-physical problems (65.0 [36.2] vs 80.2 [36.2]). Overall, 88.9% (24 of 27) of the patients were satisfied with their surgery. CONCLUSIONS: Fat injection laryngoplasty seems to be effective in enhancing acoustic and quality of life outcomes in patients with unilateral vocal cord paralysis. The effect is sustainable over 12 months.

Quality of life measures and predictors for adults with unilateral vocal cord paralysis.

OBJECTIVE/HYPOTHESIS: To investigate the quality of life (QoLF) status of Taiwanese adults with unilateral vocal cord paralysis (UVCP). STUDY DESIGN: A prospective, QoLF survey in a tertiary referral voice center. METHODS: Fifty-five consecutive UVCP patients were evaluated with Medical Outcome Study Short Form-36 (SF-36) Health Survey and the voice outcome survey at entry. RESULTS: UVCP patients have significantly lower scores in all eight SF-36 subscales (P < .05) than do normative Taiwan adult population, particularly in role functioning-physical problems, social functioning, and role functioning-emotional problems. Shimmer parameter is a robust and consistent predictor for bodily pain (beta = -20.8), role functioning-emotional problems (beta = -27.9), and social functioning (beta = -20) general health dimensions. Shimmer is also predictive of UVCP-related total voice outcome survey score (beta = -8.6, P < .05). CONCLUSIONS: UVCP can seriously compromise phonation, swallowing, and social functions; thus significantly impacting a patient's general health status. Voice physiological function is also a QoLF outcome indicator.