Keys to successful type-1 thyroplasty with Montgomery® implant for unilateral laryngeal immobility in adults.

Based on a review of the medical literature, the authors document the key technical points and pitfalls in type I thyroplasty with Montgomery® implant, and the main results and indications in unilateral laryngeal immobility.

Voice outcome indicators for unilateral vocal fold paralysis surgery: A survey among surgeons.

INTRODUCTION: Standardization of voice outcomes indicators (VOIs) is an important issue when it comes to evaluating and comparing surgical treatments for Unilateral Vocal Fold Paralysis (UVFP). In a recent review, 11 VOIs were found to represent 80% of the VOIs cited in the literature. A survey was launched among the European laryngologists to acquire surgeons' opinions on the above mentioned preselected VOIs. MATERIAL AND METHOD: The electronic survey took place between November and December 2016. Three general questions were asked about surgeon's practice setting(s) and experience. The eleven next questions concerned (a) surgeon's VOIs preference and (b) their estimates of post-operative target values, they would consider being satisfactory. RESULTS: The response rate was 16% (50 surveys). The majority of responders worked in tertiary hospitals (50%), had 15 years of experience with UVFP and performed on average 20 UVFP related procedures a year. The VOIs that were favored by the responding surgeons were, in decreasing order of importance, Voice handicap Index (VHI-30), Maximum Phonation Time (MPT), GRBAS-I, Mean Airflow Rate (MeAF), Jitter and Shimmer. There was an excellent consensus on post-operative VOI target values between survey's results and the literature data, except for three VOIs that showed somewhat divergent tendencies (absolute VHI-30, Jitter and Shimmer). CONCLUSIONS: Three VOIs are favored by surgeons: VHI-30, MPT and GRBAS-I. Jitter and Shimmer, although very frequently reported and statistically valid in the literature, come last concerning surgeon's choice as VOI for UVFP treatment assessment.

Treatment of unilateral vocal fold paralysis with ansa cervicalis to recurrent nerve anastomosis in a young adolescent: European case report.

BACKGROUND: Laryngeal re-innervation in paediatric unilateral vocal fold paralysis is a relatively new treatment option, of which there has been little reported experience in Europe. METHODS: In this European case report of a 13-year-old boy with dysphonia secondary to left-sided unilateral vocal fold paralysis after cardiac surgery, the patient underwent re-innervation using an ansa cervicalis to recurrent laryngeal nerve transfer, in combination with fat augmentation, after 12 years of nerve denervation. Perceptual analysis data, and acoustic and laryngoscopy recordings were acquired pre-operatively, and at one and two years post-operatively. RESULTS: The patient's perceptual voice quality was improved. He experienced subjective improvement and is very satisfied with the result. As expected, laryngoscopy at one and two years after surgery showed no physiological mobility of the vocal fold concerned, but improved closure during phonation was achieved. Electromyography showed evidence of re-innervation. CONCLUSION: Laryngeal re-innervation could be considered as a treatment option for unilateral vocal fold paralysis in children and adolescents, even after a long-term delay.

Very long-term Voice Handicap Index Voice Outcomes after Montgomery Thyroplasty: A cross-sectional study.

OBJECTIVE: The aim of this multicentric cross-sectional study was to examine the permanency of Montgomery thyroplasty (MTIS) results from a patient's perspective. DESIGN: The study consisted of collecting Voice Handicap Index (VHI-30) questionnaires from patients who had previously been operated with MTIS between 2 and 12 years before. Very long-term (>2 years) postoperative data were compared with the previously acquired preoperative and early postoperative VHI results. Influence of factors such as age, gender, size/side of the prosthesis and length of the follow-up were also analysed. SETTING: Multicentric study involving three tertiary European voice centres. PARTICIPANTS: Forty-nine unilateral vocal fold paralysis (UVFP) patients, treated by MTIS, were included in the study. MAIN OUTCOME MEASURES: The Voice Handicap Index-30 score. RESULTS & CONCLUSIONS: The median VHI was significantly different over time-points (Friedman's test P < .001), with a significant difference between preoperative and early postoperative time-points (median VHI: 70 vs 21, respectively; P < .001) and between preoperative and very long-term postoperative time-points (median VHI: 70 vs 16, respectively; P < .001). The median VHI did not differ for the early and very long-term postoperative time-points (median VHI: 21 vs 16; P = .470). Age differences, gender differences and size/side differences of the prostheses, centres where surgery took place and length of the follow-up showed no significant influence. Medialisation thyroplasty (MT) overall and MTIS, in particular, should be considered as a possible standard of care for UVFP when permanency of voice results is sought.

Voice outcome indicators for unilateral vocal fold paralysis surgery: a review of the literature.

INTRODUCTION: There is no consensus on which voice outcome indicators (VOIs) should be used to compare the merits of the various surgical treatments for unilateral vocal fold paralysis (UVFP). Authors performed a literature review to identify which VOIs are most frequently used and most relevant, in terms of significant change in pre- and post-operative measurements, to assess UVFP surgical treatments. METHOD: A Medline/Pubmed literature review was performed and the most frequently used VOIs were identified using a Pareto diagram. For these most frequently used VOI's, the number of studies that showed a statistically significant change in pre- and post-operative results were compared to the total number of studies found using that same VOI, this portion was expressed in percent. This percentage was defined as the "percentage of significance" and used to assess changes of each VOI. RESULTS: Eleven VOIs were identified using the Pareto analysis. These were, in decreasing order of frequency of citation: maximum phonation time (MPT), jitter, Shimmer, video-stroboscopic examination, noise to harmonic ratio (NHR/HNR), mean air flow (MeAF), fundamental frequency (F0), "Infrequent Perceptional Scales", GRBAS scale, mean subglottic pressure (MSGP). MPT, MeAF, factor G of GRBAS-I, Jitter, shimmer and VHI-30 had respective "percentage of significance" of 90, 86, 85, 74, 68 and 64%, respectively. CONCLUSION: The results indicate that MPT, MeAF and GRBAS-I, represent the top-three most frequently used and the most relevant VOIs in terms of "percentage of significance". VHI-30 showed a relatively low rate of use and low "percentage of significance". The role of Jitter and Shimmer remains unclear. Finally, MSGP and the F0 appear to be less relevant VOIs for the evaluation of UFVP surgical treatments in terms of significant change in pre- and post-operative measurements.

Laryngeal abductor reinnervation with a phrenic nerve transfer after a 9-month delay.

BACKGROUND: Successful restoration of laryngeal abductor function, using the phrenic nerve, has been described in the cat model in the acute phase. However, in clinical practice there is usually a considerable delay between injury to the RLN and presentation for treatment. Delayed reinnervation therefore would be more suitable in clinical practice. OBJECTIVE: To test the feasibility of delayed selective abductor reinnervation following transection of the recurrent laryngeal nerve (RLN). MATERIALS AND METHODS: In 12 cats, the right RLN was severed. Nine months later, the phrenic nerve was anastomosed to the distal RLN stump with all its branches directed toward the posterior cricoarytenoid muscle. For 10 weeks after the reconstruction, electromyography and videolaryngoscopy were performed weekly. Finally, histological analysis of the RLN was performed. RESULTS: Evaluation was possible in 11 cats. Reinnervation of the right posterior cricoarytenoid muscle with the phrenic nerve occurred in 10 cats following nerve anastomosis, but results of videolaryngoscopy showed adequate to good abduction in only 4 cats. The main limiting factor was reduced mobility of the cricoarytenoid joint. Evidence of spontaneous subclinical reinnervation after the delay was observed in 7 cats but apparently did not impede the surgical reinnervation. CONCLUSIONS: Delayed selective laryngeal abductor reinnervation was feasible, but function recovery was less successful than if performed immediately. Future investigations should concentrate on early determinants of spontaneous restoration of function to allow early selection of patients who are eligible for reinnervation surgery.

In vitro and in vivo comparison of the low-resistance Groningen and the Provox tracheosophageal voice prostheses.

This study has been performed to evaluate and compare two frequently used indwelling tracheoesophageal voice prostheses, the low-resistance (LR) Groningen and the Provox voice prosthesis. The airflow resistance in vitro of the Provox prosthesis has been measured and compared to our reported results of the LR Groningen prosthesis. The in vivo study involved fifteen non-myotomized laryngectomees who randomly received one of the two prostheses. Measurements were performed of the intratracheal phonatory pressure and of voice parameters. The intelligibility of speech in noise was evaluated in eight patients. Patients preferences regarding the two prostheses were assessed. Aerodynamic measurements show the Provox voice prosthesis to have a lower airflow resistance. The median intratracheal phonatory pressure for phonation of 75 dB was significantly lower (2.1 kPa) in patients using the Provox voice prosthesis. Speech rate, maximal phonation time and maximal vocal intensity showed no significant difference. The intelligibility of speech in noise produced with the Provox was significantly better than the speech produced with the LR Groningen prosthesis. Subjectively, most patients preferred the Provox prosthesis because speech required less effort. Patients with a hypotonic pharyngoesophageal segment tended to prefer the LR Groningen prosthesis.

Reinnervation aspects of laryngeal transplantation.

Although restoration of laryngeal function after laryngeal transplantation depends on appropriate reinnervation, non-selective reinnervation procedures result in synkinesis and poor function restoration. This study was performed to test the feasibility of selective reinnervation procedures to restore laryngeal function. Three surgical reinnervation procedures were studied each in a group of ten cats: in group 1 a non-selective procedure in which the recurrent laryngeal nerve (RLN) was cut and reanastomosed; in group 2 selective abductor reinnervation was performed with the phrenic nerve; in group 3 selective abductor reinnervation with the phrenic nerve (PN) was combined with selective adductor reinnervation with the ansa cervicalis. Ten weeks after surgical reinnervation abductor and reflex adductor functions were evaluated with videolaryngoscopy and electromyography. Findings demonstrated that non-selective reinnervation not only gave poor abduction during inspiration but even resulted in paradoxical movement during reflex adduction. Selective abductor reinnervation resulted in good abductor function. Selective adductor reinnervation with the ansa cervicalis brought about muscle tonus in the animals studied but no restoration of reflex adduction. Enhanced activity during respiratory distress gave only slight compromise to the abductor function. In all, selective laryngeal reinnervation with the PN and ansa cervicalis produced good restoration of respiratory laryngeal function. However, deglutition following laryngeal motor and sensory reinnervation with protection of the respiratory tract is probably not sufficient, as in the present group of animals no reflex glottic closure was achieved. More research is required.

Selective laryngeal reinnervation with separate phrenic and ansa cervicalis nerve transfers.

OBJECTIVE: To perform selective reinnervation of the laryngeal abductor and adductor muscle groups after injury to the recurrent laryngeal nerve, recovering laryngeal function without impairment by synkinesis. DESIGN: Ten cats underwent the surgical procedure. To reinnervate the posterior cricoarytenoid muscle (abductor), a phrenic nerve graft was anastomosed to the main trunk of the recurrent laryngeal nerve. The adductor branch was severed, and the proximal stump was buried in the posterior cricoarytenoid muscle. The sternohyoid branch of the ansa cervicalis was anastomosed to the distal stump to reinnervate the adductor muscle group. After a period of 10 weeks, the laryngeal function was evaluated with videolaryngoscopy and electromyography of the posterior circoarytenoid and vocalis muscles. RESULTS: Of the 10 cats, 9 could be evaluated. Laryngeal abductor function was comparable with the unaffected side in the 9 cats. During respiratory distress conditions, a minor compromise of the maximal abduction was observed in 5 cats. Phonation was not tested, but spontaneous adduction during expiration was seen in all cats. Reflex closure on ipsilateral, supraglottic, tactile mucosal stimulation was seen in only 2 cats. In each cat, evidence of nerve regeneration and reinnervation of both muscle groups was established with electromyography, electrical stimulation, and histological examination. CONCLUSIONS: Using this selective reinnervation procedure, good laryngeal function can be achieved in the cat model, which may be applicable in humans. By reinnervation of the vocalis muscle, muscle tonus is achieved, which is expected to improve voice quality. Using this procedure, however, no active reflex closure may be expected.

Laryngeal reinnervation surgery - results of a selective approach in an animal study.

Laryngeal reinnervation surgery is a difficult subject due to the fact that the recurrent laryngeal nerve (RLN) is responsible for both adductor and abductor laryngeal activity. Non-selective reinnervation procedures will result in laryngeal synkinesis with restoration of tonicity. Restoration of mobility requires selective reinnervation of the adductor and abductor branches with nerves with similar activity patterns as the initial abductor and adductor branches of the RLN.

Laryngeal abductor function after recurrent laryngeal nerve injury in cats.

OBJECTIVE: To determine the influence of severity of neural injury of t he recurrent laryngeal nerve on recovery of laryngeal abductor function and the importance of synkinesis. DESIGN: The recovery of laryngeal abductor function was studied in 30 cats after crushing (second-degree injury) or transection followed by neurorrhaphy (fifth-degree injury) of the recurrent laryngeal nerve, with a reinnervation period of 10 weeks. MAIN OUTCOME MEASURES: Recovery of laryngeal abductor function was evaluated by videolaryngoscopy of spontaneous laryngeal abduction during respiration and electromyography of the posterior cricoarytenoid and vocalis muscles. Neural lesions were applied unilaterally, and recovery of laryngeal function was compared with the contralateral unimpaired hemilarynx. Reinnervation was confirmed by histologic examination. RESULTS: After the recurrent laryngeal nerve was crushed, laryngeal abductor function was similar to normal after a 10-week reinnervation period in 19 of the 20 cats; after neurorrhaphy, no notable recovery of laryngeal abduction resulted in any of 10 cats. Electromyographic recordings disclosed synkinesis after neurorrhaphy and recovery of normal activity patterns after crush injuries. CONCLUSIONS: Severity of neural injury to the recurrent laryngeal nerve influences the recovery of laryngeal abductor function. Damage to the endoneurium leads to misdirection of regenerating axons, inappropriate reinnervation, and synkinesis. No effective laryngeal function can then be expected.

Selective laryngeal abductor reinnervation in cats using a phrenic nerve transfer and ORG 2766.

Reinnervation of the recurrent laryngeal nerve following nerve injury often leads to laryngeal synkinesis. Selective reinnervation of adductor and abductor muscles might be able to avoid synkinesis. This study presents the results of selective abductor reinnervation in cats, using a phrenic nerve transfer to the recurrent laryngeal nerve and directing all reinnervating axons toward the abductor muscle. Simultaneously, a blind, placebo-controlled, pilot study was performed to evaluate the capacity of ORG 2766, administered subcutaneously (25 micrograms/kg per 48 hours), to facilitate reinnervation by stimulation of axon sprouting. Reinnervation surgery was performed in 10 cats. Postoperative evaluation included videolaryngoscopy, electromyography, histological examination, and quantification of reinnervating axons. Nine cats could be evaluated, of which eight demonstrated electromyographic and laryngoscopic activity as soon as 6 weeks following surgery. The one cat showing no abduction was found to have an inadequate nerve anastomosis and was marked as a surgical failure. After 10 weeks, near-normal or more than normal abduction was seen in the eight cats, and histological proof of reinnervation was obtained in seven of them; one cat could not be evaluated histologically owing to unsuccessful fixation. Although no conclusive evidence was obtained concerning the effect of ORG 2766, the tendencies found warrant further experiments with this compound on laryngeal reinnervation.

Clinical experience with the low-resistance Groningen button.

Since its introduction in 1980, the standard Groningen button prosthesis has been of proven value for post-laryngectomy voice rehabilitation. Its relatively high airflow resistance has, however, been the cause of failure in achieving good post-laryngectomy tracheoesophageal shunt speech in some patients. The low-resistance Groningen button (LRGB) was therefore designed, thus reducing airflow resistance by 50% when compared to the standard device. The clinical performance of the LRGB, and the effect of prophylactic amphotericin, was assessed in 32 patients. The device lifetime, intratracheal phonatory pressures and patients' subjective acceptances of the prosthesis were recorded. Present findings showed that the majority of the patients preferred the LRGB as it required less effort to operate than the standard device. The intra-tracheal phonatory pressure was found to increase with time, but this change was prevented with the prophylactic use of amphotericin to inhibit concurrent colonization by Candida spp, which also helped to prolong the prosthesis lifetime.

Aerodynamic properties of the low-resistance Groningen button.

Shunt tracheoesophageal speech is currently the most successful form of voice and speech rehabilitation in laryngectomees. Insertion of valve prostheses into the tracheoesophageal shunts has overcome drawbacks caused by stenosis of the shunt and aspiration. In 10 years of satisfactory results with the standard Groningen button valve prosthesis, the overall concept of this device has proved its value. The airflow resistance, however, is relatively high, so that a low-resistance device has been developed without changing the favorable characteristics of the standard device. The design of this low-resistance Groningen button is described. The airflow resistances of the standard and low-resistance Groningen buttons have been measured and compared. The airflow resistance of the low-resistance Groningen button is also compared with the reported airflow resistances of various other valve prostheses.