Polydimethylsiloxane Particles for Permanent Injection Laryngoplasty

Complications of Polydimethylsiloxane for Injection Laryngoplasty: Retrospective Case Series of 10 Patients Requiring Explant and Literature Review

Polydimethylsiloxane (PDMS) has been reported in the literature as a safe and permanent material for injection laryngoplasty (IL)1 We present a case series of 10 patients who had undergone PDMS-IL at external campuses which resulted in unsatisfactory voice outcomes and were managed with explant. A literature review on PDMS-IL associated complications is presented. In our series, seven out of ten patients (70%) with voice outcomes data, developed an improved voice post PDMS explant. Seven out of ten patients (70%) had improved vocal fold pliability with two patients (20%) having irretrievably damaged pliability due to the PDMS disturbing the superficial lamina propria. All eight patients with specimens submitted for histopathology had foreign body inflammation reported. There were ten additional cases reported in the literature with post PDMS adverse outcomes managed with explant. In the literature, explant improved the voice in seven out of nine patients (78%) with reported voice outcomes and partially restored vocal fold pliability in five out of six patients (83%) which commented on this outcome. PDMS-IL carries a risk of irreversible loss of vocal fold pliability which should be informed to the patient as part of the preoperative informed consent.

Active and Passive Bioimplants for Vocal Fold Paralysis

Vocal fold paralysis is one of the diseases that particularly affect quality of life. While unilateral paralysis leads to glottis closure insufficiency and hoarseness, bilateral paralysis compromises respiration and limits the exercise tolerance. Bioimplants have been used to treat persistent paralysis for over 100 years. The spectrum ranges from autologous tissue transfer and resorbable or permanent injection materials to composite thyroplasty implants and active electrical implants for neurostimulation of the larynx. If bioimplants are used in accordance with the recommendations, the quality of life of affected patients can be significantly improved today.

Surgical rehabilitation of swallowing with polydimethylsiloxane injections after open partial horizontal laryngectomy: Long-term functional results and quality of life

BACKGROUND

Swallowing disorders are common problems after partial laryngectomy. The aim of this study is to illustrate the long-term functional results of rehabilitation of swallowing by polydimethylsiloxane (PDMS) injection.

METHODS

Twenty-eight patients with dysphagia after partial laryngectomy who underwent injection of PDMS for rehabilitation of swallowing were included in the study. Impairment of swallowing and quality of life (QoL) were investigated with questionnaires: M. D. Anderson Dysphagia Inventory (MDADI) and Performance Status Scale for Head and Neck Cancer (PSS-HNC). Functional results at fiberoptic endoscopic evaluation of swallowing (FEES) were analyzed using a modified penetration-aspiration scale.

RESULTS

Mean follow-up was 8.5 years. Twenty-six patients showed an improvement at questionnaires (p < 0.001). Median improvement was 6 (p < 0.001) in the modified penetration-aspiration scale. Total laryngectomy was required in one patient.

CONCLUSIONS

PDMS injection is a good option for rehabilitation of swallowing in case of dysphagia after partial laryngectomy. It improves QoL and the results persist after a long follow-up period.

[Update on vocal fold augmentation]

Unilateral vocal fold palsy is a frequent cause of hoarseness. In the presence of glottis closure insufficiency, the effectiveness of conservative voice therapy is often limited and phonosurgery may be indicated. Injection laryngoplasty is effective for correction of insufficiency. Early intervention during the first 6 months after diagnosis is desired to avoid subsequent insufficient endogenous compensation. Particularly patients with glottic closure insufficiency ≤2 mm in stroboscopy may benefit from this procedure. With appropriate patient selection, duration of the effect exceeding 12 months has been described for hyaluronic acid, calcium hydroxylapatite, and autologous fat. Due to rare complications such as allergic swelling at the injection site, regular laryngoscopic monitoring and observation for two nights after injection are recommended. The voice must only be rested for a few hours.

Vocal fold medialization-A 5-year series of single surgeon consecutive medialization with review of literature

INTRODUCTION

ENT UK released guidelines in 2010 detailing the requisite structure for the creation of a laryngeal intervention clinic. The senior author's practice is the only one regionally that offers this service, and our objective was to review this to determine whether vocal cord medialization injections were showing an improvement in quality of voice for patients.

MATERIALS AND METHODS

Patients were reviewed in a specialist voice clinic prior to being offered vocal cord injection under local anaesthetic in a separate dedicated weekly clinic. They would be assessed by the senior author and a dedicated voice specialist speech and language therapist (SALT). This would include a preinjection grade, roughness, breathiness, asthenia, and strain (GRBAS), Voice Handicap Index (VHI)-10, and the measuring of maximum phonation time (MPT) with the aid of Opera Vox Apple iPad application.

RESULTS

Data were available for 186 injections, on patients with a median age of 66 years (interquartile range [IQR]: 51-75), of whom 61% were male. VHI-10 score improved significantly, from a mean of 26.7 to 12.5 (P < .001). A significant improvement in MPT was also observed, from a median of 3.0 to 6.3 (N = 66, P < .001). Improvements in all components of the GRBAS score were also observed (all P < .001), with between 43% and 88% of cases reporting reductions after the procedure. Patients receiving a repeat procedure saw a significantly smaller improvement in VHI-10 than those where it was the primary treatment (mean reduction: 9.8 vs 15.5, P = .018). Analysis of MPT found a significant correlation between the quantity of injection material used and the degree of improvement observed (rho = 0.355, P = .004).

CONCLUSION

Vocal Cord local anaesthetic medialization injection is a swift, safe, and effective short-term method of improving dysphonia.

Clinical Practice Guideline: Hoarseness (Dysphonia) (Update)

Objective

This guideline provides evidence-based recommendations on treating patients who present with dysphonia, which is characterized by altered vocal quality, pitch, loudness, or vocal effort that impairs communication and/or quality of life. Dysphonia affects nearly one-third of the population at some point in its life. This guideline applies to all age groups evaluated in a setting where dysphonia would be identified or managed. It is intended for all clinicians who are likely to diagnose and treat patients with dysphonia.

Purpose

The primary purpose of this guideline is to improve the quality of care for patients with dysphonia, based on current best evidence. Expert consensus to fill evidence gaps, when used, is explicitly stated and supported with a detailed evidence profile for transparency. Specific objectives of the guideline are to reduce inappropriate variations in care, produce optimal health outcomes, and minimize harm. For this guideline update, the American Academy of Otolaryngology—Head and Neck Surgery Foundation selected a panel representing the fields of advanced practice nursing, bronchoesophagology, consumer advocacy, family medicine, geriatric medicine, internal medicine, laryngology, neurology, otolaryngology–head and neck surgery, pediatrics, professional voice, pulmonology, and speech-language pathology.

Action Statements

The guideline update group made strong recommendations for the following key action statements (KASs): (1) Clinicians should assess the patient with dysphonia by history and physical examination to identify factors where expedited laryngeal evaluation is indicated. These include, but are not limited to, recent surgical procedures involving the head, neck, or chest; recent endotracheal intubation; presence of concomitant neck mass; respiratory distress or stridor; history of tobacco abuse; and whether the patient is a professional voice user. (2) Clinicians should advocate voice therapy for patients with dysphonia from a cause amenable to voice therapy. The guideline update group made recommendations for the following KASs: (1) Clinicians should identify dysphonia in a patient with altered voice quality, pitch, loudness, or vocal effort that impairs communication or reduces quality of life (QOL). (2) Clinicians should assess the patient with dysphonia by history and physical examination for underlying causes of dysphonia and factors that modify management. (3) Clinicians should perform laryngoscopy, or refer to a clinician who can perform laryngoscopy, when dysphonia fails to resolve or improve within 4 weeks or irrespective of duration if a serious underlying cause is suspected. (4) Clinicians should perform diagnostic laryngoscopy, or refer to a clinician who can perform diagnostic laryngoscopy, before prescribing voice therapy and document/communicate the results to the speech-language pathologist (SLP). (5) Clinicians should advocate for surgery as a therapeutic option for patients with dysphonia with conditions amenable to surgical intervention, such as suspected malignancy, symptomatic benign vocal fold lesions that do not respond to conservative management, or glottic insufficiency. (6) Clinicians should offer, or refer to a clinician who can offer, botulinum toxin injections for the treatment of dysphonia caused by spasmodic dysphonia and other types of laryngeal dystonia. (7) Clinicians should inform patients with dysphonia about control/preventive measures. (8) Clinicians should document resolution, improvement or worsened symptoms of dysphonia, or change in QOL of patients with dysphonia after treatment or observation. The guideline update group made a strong recommendation against 1 action: (1) Clinicians should not routinely prescribe antibiotics to treat dysphonia. The guideline update group made recommendations against other actions: (1) Clinicians should not obtain computed tomography (CT) or magnetic resonance imaging (MRI) for patients with a primary voice complaint prior to visualization of the larynx. (2) Clinicians should not prescribe antireflux medications to treat isolated dysphonia, based on symptoms alone attributed to suspected gastroesophageal reflux disease (GERD) or laryngopharyngeal reflux (LPR), without visualization of the larynx. (3) Clinicians should not routinely prescribe corticosteroids for patients with dysphonia prior to visualization of the larynx. The policy level for the following recommendation about laryngoscopy at any time was an option: (1) Clinicians may perform diagnostic laryngoscopy at any time in a patient with dysphonia.

Disclaimer

This clinical practice guideline is not intended as an exhaustive source of guidance for managing dysphonia (hoarseness). Rather, it is designed to assist clinicians by providing an evidence-based framework for decision-making strategies. The guideline is not intended to replace clinical judgment or establish a protocol for all individuals with this condition, and it may not provide the only appropriate approach to diagnosing and managing this problem. Differences from Prior Guideline (1) Incorporation of new evidence profiles to include the role of patient preferences, confidence in the evidence, differences of opinion, quality improvement opportunities, and any exclusion to which the action statement does not apply (2) Inclusion of 3 new guidelines, 16 new systematic reviews, and 4 new randomized controlled trials (3) Inclusion of a consumer advocate on the guideline update group (4) Changes to 9 KASs from the original guideline (5) New KAS 3 (escalation of care) and KAS 13 (outcomes) (6) Addition of an algorithm outlining KASs for patients with dysphonia

Polydimethylsiloxane Injection Laryngoplasty for Unilateral Vocal Fold Paralysis: Long-Term Results

OBJECTIVES

To analyze the long-term objective, perceptive, and subjective outcomes after endoscopic polydimethylsiloxane (PDMS) injection laryngoplasty in unilateral vocal fold paralysis.

STUDY DESIGN

A retrospective study carried out between January 2008 and January 2012.

SETTING

Head and Neck Department, University Hospital of Modena, Modena, Italy.

METHODS

This was a retrospective analysis of 26 patients with unilateral vocal fold paralysis who underwent endoscopic injection of PDMS under general anesthesia. A voice evaluation protocol was performed for all patients, which included videolaryngostroboscopy, maximum phonation time, fundamental frequency, analysis of the harmonic structure of the vowel /a/ and the word /aiuole/, Grade of Dysphonia, Instability, Roughness, Breathiness, Asthenia, and Strain scale, and Voice Handicap Index. The protocol was performed before surgery, in the immediate postoperative period, and at least 3 years after surgery. The mean follow-up period was 73 months (range 39-119 months).

RESULTS

The statistical analysis showed a significant improvement (P < 0.01) for all of the objective, perceptive, and subjective parameters by comparison between the preoperative and long-term follow-up data; moreover, no statistically significant difference was found between the postoperative and long-term follow-up data. This indicates that injection laryngoplasty with PDMS guarantees long-lasting effects over time. No complications were reported in our series.

CONCLUSION

Injection laryngoplasty with PDMS can be considered to be a minimally invasive and safe technique for the treatment of unilateral vocal fold paralysis. Moreover, it allows very good and stable results to be obtained over time, avoiding repeated treatments and improving the quality of life of the patients.

[Glottis injection to improve voice function : Review of more than 500 operations]

BACKGROUND

Hoarseness due to insufficient glottal closure can be treated by injection laryngoplasty (augmentation). Vocal fold injections can be performed as an in-office procedure or under general anesthesia. As injection materials have recently improved and different injection approaches are available, injection laryngoplasties are performed much more frequently.

OBJECTIVES

Advantages and disadvantages of injection materials, laryngeal approaches, and differential indications are described.

MATERIALS AND METHODS

Literature research and experience of more than 500 laryngeal injection procedures are provided.

RESULTS AND CONCLUSIONS

Sophisticated use of available injection materials can provide a satisfying improvement of voice function with minimal patient discomfort. Adequate indication is mandatory for a favorable outcome. Further improvement regarding biocompatibility and the duration of injection materials is desirable.

Vocal fold scars: current concepts and future directions. Consensus report of the Phonosurgery Committee of the European Laryngological Society

Scarring of the vocal folds leads to a deterioration of the highly complex micro-structure with consecutively impaired vibratory pattern and glottic insufficiency. The resulting dysphonia is predominantly characterized by a reduced vocal capacity. Despite the considerable progress in understanding of the underlying pathophysiology, the treatment of scarred vocal folds is still an unresolved chapter in laryngology and phonosurgery. Essential for a successful treatment is an individual, multi-dimensional concept that comprises the whole armamentarium of surgical and non-surgical (i.p. voice therapy) modalities. An ideal approach would be to soften the scar, because the reduced pliability and consequently the increased vibratory rigidity impede the easiness of vibration. The chosen phonosurgical method is determined by the main clinical feature: Medialization techniques for the treatment of glottic gap, or epithelium freeing techniques for improvement of vibration characteristics often combined with injection augmentation or implantation. In severe cases, buccal mucosa grafting can be an option. New developments, include treatment with anxiolytic lasers, laser technology with ultrafine excision/ablation properties avoiding coagulation (Picosecond infrared laser, PIRL), or techniques of tissue engineering. However, despite the promising results by in vitro experiments, animal studies and first clinical trials, the step into clinical routine application has yet to be taken.

Alternative injectable materials for vocal fold medialisation in unilateral vocal fold paralysis

BACKGROUND

Patients with unilateral vocal fold paralysis (UVFP) usually present with dysphonia, but can also be breathless and have problems with their swallowing. Speech and language therapy forms the initial mainstay of management in cases of UVFP, since up to 60% of cases will resolve spontaneously. If vocal fold paralysis persists surgery, in the form of injection medialisation, has been shown to be an effective intervention. What is currently unclear is which is the most effective material available for injection.

OBJECTIVES

To assess the effectiveness of alternative injection materials in the treatment of UVFP.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 23 March 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of injectable materials in patients with UVFP. The outcomes of interest were patient and clinician-reported improvement, and adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies from the search results and extracted data. We used the Cochrane 'Risk of bias' tool to assess study quality.

MAIN RESULTS

We identified no RCTs which met the inclusion criteria for this review. We excluded 18 studies on methodological grounds: 16 non-randomised studies; one RCT due to inadequate randomisation and inclusion of non-UVFP patients; and one RCT which compared two different particle sizes of the same injectable material.

AUTHORS' CONCLUSIONS

There is currently insufficient high-quality evidence for, or against, specific injectable materials for patients with UVFP. Future RCTs should aim to provide a direct comparison of the alternative materials currently available for injection medialisation.

Posterior glottic gap and age as factors predicting voice outcome of injection laryngoplasty in patients with unilateral vocal fold paralysis

Objectives:

This study aimed to analyse demographic profiles and pre-injection stroboscopic findings for patients with unilateral vocal fold paralysis, to investigate possible predictive factors for voice outcomes of injection laryngoplasty.

Materials and methods:

Fifty-nine unilateral vocal fold paralysis patients underwent vocal fold augmentation, using transcutaneous Artecoll (polymethyl methacrylate microspheres plus bovine collagen) injection into the paralysed vocal fold via the cricothyroid space. Three months later, patients were divided into improved (n = 44) and unimproved (n = 15) groups, using the perceptual grade-roughness-breathiness-asthenia-strain scale, and their clinical characteristics and pre-operative stroboscopic findings compared.

Results:

The improved group were significantly younger than the unimproved group (p = 0.000). The size of the posterior gap on phonation was closely associated with the outcome of injection laryngoplasty (p = 0.015).

Conclusion:

Younger patients with a smaller posterior glottic gap on phonation can be expected to have a more favourable outcome following injection laryngoplasty for correction of glottic insufficiency due to unilateral vocal fold paralysis.

Larynx: implants and stents

In the human larynx, implants a primarily used for the correction of glottis insufficiency. In a broader sense laryngeal stents may be considered as implants as well. Laryngeal implants can be differentiated into injectable and solid. The most important representatives of both groups are discussed in detail along with the respective technique of application. Laryngeal stents are primarily used perioperatively. Different types and their use are presented.

Vocal fold injection: review of indications, techniques, and materials for augmentation

Vocal fold injection is a procedure that has over a 100 year history but was rarely done as short as 20 years ago. A renaissance has occurred with respect to vocal fold injection due to new technologies (visualization and materials) and new injection approaches. Awake, un-sedated vocal fold injection offers many distinct advantages for the treatment of glottal insufficiency (vocal fold paralysis, vocal fold paresis, vocal fold atrophy and vocal fold scar). A review of materials available and different vocal fold injection approaches is performed. A comparison of vocal fold injection to laryngeal framework surgery is also undertaken. With proper patient and material selection, vocal fold injection now plays a major role in the treatment of many patients with dysphonia.

MR evaluation of PDMS injections in head and neck tissues: a pilot study

OBJECTIVES

To describe the magnetic resonance (MR) appearance of polydimethylsiloxane (PDMS) injections in the head and neck region.

STUDY DESIGN

Retrospective review of MR images from a case series.

METHODS

MR images of 10 patients, who underwent PDMS injections at our department, were reviewed. Data from imaging were collected and analyzed.

RESULTS

After injection, PDMS can be identified in MR images, particularly in T2-weighted images in the early stages. Its MR characteristics are similar to silicone in other regions, but with time, its appearance can change.

CONCLUSIONS

The integration of PDMS with tissues may also be reflected in changes in MR appearance, as a result of an increased amount of fibrous tissue in the region injected. Radiologists and ENT specialists may benefit from knowledge of the MR characteristics and variability in appearance of PDMS in human tissues for improving image interpretation.

Clinical Practice Guideline: Hoarseness (Dysphonia)

Objective:

This guideline provides evidence-based recommendations on managing hoarseness (dysphonia), defined as a disorder characterized by altered vocal quality, pitch, loudness, or vocal effort that impairs communication or reduces voice-related quality of life (QOL). Hoarseness affects nearly one-third of the population at some point in their lives. This guideline applies to all age groups evaluated in a setting where hoarseness would be identified or managed. It is intended for all clinicians who are likely to diagnose and manage patients with hoarseness.

Purpose:

The primary purpose of this guideline is to improve diagnostic accuracy for hoarseness (dysphonia), reduce inappropriate antibiotic use, reduce inappropriate steroid use, reduce inappropriate use of anti-reflux medications, reduce inappropriate use of radiographic imaging, and promote appropriate use of laryngoscopy, voice therapy, and surgery. In creating this guideline the American Academy of Otolaryngology—Head and Neck Surgery Foundation selected a panel representing the fields of neurology, speech-language pathology, professional voice teaching, family medicine, pulmonology, geriatric medicine, nursing, internal medicine, otolaryngology–head and neck surgery, pediatrics, and consumers.

Results

The panel made strong recommendations that 1) the clinician should not routinely prescribe antibiotics to treat hoarseness and 2) the clinician should advocate voice therapy for patients diagnosed with hoarseness that reduces voice-related QOL. The panel made recommendations that 1) the clinician should diagnose hoarseness (dysphonia) in a patient with altered voice quality, pitch, loudness, or vocal effort that impairs communication or reduces voice-related QOL; 2) the clinician should assess the patient with hoarseness by history and/or physical examination for factors that modify management, such as one or more of the following: recent surgical procedures involving the neck or affecting the recurrent laryngeal nerve, recent endotracheal intubation, radiation treatment to the neck, a history of tobacco abuse, and occupation as a singer or vocal performer; 3) the clinician should visualize the patient's larynx, or refer the patient to a clinician who can visualize the larynx, when hoarseness fails to resolve by a maximum of three months after onset, or irrespective of duration if a serious underlying cause is suspected; 4) the clinician should not obtain computed tomography or magnetic resonance imaging of the patient with a primary complaint of hoarseness prior to visualizing the larynx; 5) the clinician should not prescribe anti-reflux medications for patients with hoarseness without signs or symptoms of gastroesophageal reflux disease; 6) the clinician should not routinely prescribe oral corticosteroids to treat hoarseness; 7) the clinician should visualize the larynx before prescribing voice therapy and document/communicate the results to the speech-language pathologist; and 8) the clinician should prescribe, or refer the patient to a clinician who can prescribe, botulinum toxin injections for the treatment of hoarseness caused by adductor spasmodic dysphonia. The panel offered as options that 1) the clinician may perform laryngoscopy at any time in a patient with hoarseness, or may refer the patient to a clinician who can visualize the larynx; 2) the clinician may prescribe anti-reflux medication for patients with hoarseness and signs of chronic laryngitis; and 3) the clinician may educate/counsel patients with hoarseness about control/preventive measures.

Disclaimer:

This clinical practice guideline is not intended as a sole source of guidance in managing hoarseness (dysphonia). Rather, it is designed to assist clinicians by providing an evidence-based framework for decision-making strategies. The guideline is not intended to replace clinical judgment or establish a protocol for all individuals with this condition, and may not provide the only appropriate approach to diagnosing and managing this problem.

[Surgical voice rehabilitation in unilateral vocal fold paralysis]

Unilateral recurrent nerve paralysis leads to glottic insufficiency, significantly reducing vocal ability. Due to its unusually long course, the recurrent laryngeal nerve is prone to iatrogenic lesions involves many medical fields generally with little expertise in voice disorders. Whenever the etiology is uncertain, a complete diagnostic work-up is mandatory. Indirect laryngoscopy confirms the diagnosis. Laryngeal electromyography is of great value because it differentiates between paralysis and ankylosis of the cricoarytenoid joint. Moreover in many cases laryngeal electromyography yields a reliable prognosis of clinical outcome. While unfavorable results can be predicted with high accuracy, correct prognosis of complete recovery is more difficult. Speech therapy is the treatment of choice in cases of unilateral recurrent nerve palsy. Patients with persistent glottal gap may express the wish for surgical voice rehabilitation. Nowadays a broad spectrum of endoscopic and open approaches are available for this purpose. This review describes advanced techniques of voice-improving surgery available in specialized centers today.

Therapy of unilateral vocal fold paralysis with polydimethylsiloxane injection laryngoplasty: our experience

The objective of this study was to document functional results and to compare objective and subjective voice measures after endoscopic laryngoplasty with injection of polydimethylsiloxane (PDMS) for the treatment of unilateral vocal fold paralysis, and to verify PDMS biocompatibility in vocal fold. The design used was a longitudinal prospective study. Fifteen patients with unilateral vocal fold paralysis underwent endoscopic injection of PDMS in general anesthesia. Accurate voice evaluation protocol (acoustic and aerodynamics analyses, GIRBAS [Grade, Instability, Roughness, Breathiness, Asthenia, and Strain] scale, videostrobolaryngoscopy, and Voice Handicap Index test) before, after surgery, and at follow-up time was performed. The median follow-up was 21.7 months (range, 6-35). Data obtained were statistically significant. All acoustic, aerodynamics, perceptive, and subjective evaluations showed a significant improvement. No complications due to PDMS were reported. Functional results were found comparable to framework surgery. Endoscopic injection laryngoplasty with PDMS is a safe and long-term option for treatment of unilateral vocal fold paralysis.

[Laryngopharyngeal morbidity following general anaesthesia. Anaesthesiological and laryngological aspects]

Laryngeal and pharyngeal complaints are among the subjective problems most frequently reported by patients after general anaesthesia involving endotracheal intubation, others being pain, nausea and vomiting. Hoarseness, sore throat, and vocal cord injuries restrict patients' social lives, and in some cases also their working lives. The most frequent types of laryngeal injury are swollen mucosa and haematoma of the vocal cords. Vocal cord paralysis occurs much less frequently. Knowledge of the pathophysiological aspects and other relevant factors associated with laryngopharyngeal morbidity are essential cornerstones of quality assurance in perioperative respiratory tract management. In this review specific sections are devoted to the implications of anaesthesia involving endotracheal intubation and laryngeal masks for laryngopharyngeal morbidity, and also particular aspects of thyroid gland surgery, cardiothoracic and bariatric surgery and obstetric and paediatric anaesthesia, and medicolegal aspects.

Transcutaneous injection laryngoplasty through the cricothyroid space in the sitting position: anatomical information and technique

A variety of approaches have been introduced to perform injection laryngoplasty under local anesthesia. Among these reported methods, transcutaneous injection through the cricothyroid space offers many advantages, but it possesses some technical difficulties during access to the vocal fold. The aim of this study was to assess the anatomic references related to transcutaneous injection laryngoplasty through cricothyroid space using 3-dimensionally reconstructed computed tomography to provide guidelines and to achieve higher efficacy during the procedure. The study group consisted of 14 patients (7 male, 7 female) with unilateral vocal fold paralysis and who had undergone multi-detector array computed tomography (MDCT) between January 2004 and December 2005. Assumption was made that transcutaneous injection is approached from the surface at lower margin of the thyroid cartilage and 7 mm lateral to the midline through the cricothyroid membrane and spot at the posterior 1/3 of true vocal cord is the target for injection laryngoplasty. From the surface of the injection point to the target, a line was drawn. Its length and the angle formed between it and the approach direction of needle was measured. Based on these measurements, 15 patients (8 male, 7 female) with unilateral vocal fold paralysis received 15 trials of transcutaneous injection laryngoplasty through the cricothyroid space. The average length from the surface of the injection point (7 mm lateral to the midline) to the posterior 1/3 of the true vocal cord (target of the injection) was 15.75 mm in men and 13.91 mm in women. The average of the angle in medial direction at the surface needed to reach the target of the injection was 10.57 degrees in men and 12.71 degrees in women, and in superior direction was 47.57 degrees in men and 47.43 degrees in women. Injection laryngoplasty performed under acquired reference measurements were successful in 14 trials (93.3%) out of 15 trials in 15 patients. We suggest that knowledge of the anatomic references regarding the transcutaneous injection laryngoplasty through cricothyroid space will provide guidelines for beginners and improve the understanding of the procedure, eventually leading to easier and more precise access to the vocal cord.

Rejection of injectable silicone “Bioplastique” used for vocal fold augmentation

A rare case of repeated granulomatous inflammation after silicone injection laryngoplasty for vocal fold immobility as well as its treatment by endoscopic approach is reported. The patient presented a right-sided vocal fold immobility after laryngeal trauma and remained dysphonic despite of logopedic voice therapy because of severe glottal insufficiency. An endoscopic transoral intrafold silicone injection was applied to improve the vocal function. Silicone granuloma inflammation was observed 8 days after the vocal fold augmentation. Oral broad-spectrum antibiotics and corticosteroids did not improve the inflammation. A cordotomy was performed to remove the silicone implant. After 3 months, a second endoscopic surgical intervention was necessary to remove a recurrent silicone granuloma. Eight months after the second surgical intervention, the inflammation had disappeared. An autologous fat injection to restore the glottal closure was performed successfully. Type IV contact allergy was excluded with an epicutaneous patch and scratch test with components of the silicone implant. Clinical and treatment observations are reported and the literature on complications of intrafold injected silicone for vocal fold augmentation is reviewed.