To propose a scoring system based on laryngoscopic characteristics for the differential diagnosis of benign and malignant vocal fold leukoplakia.

Laryngoscopic images from 200 vocal fold leukoplakia cases were retrospectively analysed. The laryngoscopic signs of benign and malignant vocal fold leukoplakia were compared, and statistically significant features were assigned and accumulated to establish the leukoplakia finding score.

A total of five indicators associated with malignant vocal fold leukoplakia were included to construct the leukoplakia finding score, with a possible range of 0–10 points. A score of 6 points or more was indicative of a diagnosis of malignant vocal fold leukoplakia. The sensitivity, specificity and accuracy values of the leukoplakia finding score were 93.8 per cent, 83.6 per cent and 86.0 per cent, respectively. The consistency in the leukoplakia finding score obtained by different laryngologists was strong (kappa = 0.809).

This scoring system based on laryngoscopic characteristics has high diagnostic value for distinguishing benign and malignant vocal fold leukoplakia.

This case report discusses a successful emergency Lichtenberger lateralisation procedure after immediate bilateral laryngeal immobility, occurring after total thyroidectomy.

A 63-year-old female with right-sided vocal fold paralysis due to compression by a multinodular thyroid goitre underwent total thyroidectomy, which resulted in immediate post-operative bilateral vocal fold immobility. The patient had acute-onset post-operative dyspnoea, was promptly re-intubated, and an emergency lateralisation Lichtenberger suture was placed over the right vocal fold and fixated on the outer surface of the neck.

After two weeks, her right vocal fold recovered first, with the suture still in place. At four weeks, both vocal folds regained function and the suture was extracted.

The take-away message is that an emergency lateralisation suture may be a viable option in maintaining airway patency, while allowing for normal deglutition, in patients who would otherwise be candidates for prolonged intubation, posterior cordotomy, medial arytenoidectomy or tracheostomy.

There is a paucity of Asian-based data regarding the diagnostic yield of computed tomography imaging in the initial assessment of idiopathic unilateral vocal fold palsy.

To investigate the diagnostic yield of computed tomography in idiopathic unilateral vocal fold palsy cases in an Asian tertiary hospital, and to determine the causative pathologies and positive predictive factors.

A retrospective chart review was conducted of patients (between 2010 and 2018) with a clinical diagnosis of idiopathic unilateral vocal fold palsy who underwent contrast-enhanced computed tomography of the neck and chest at Tan Tock Seng Hospital, Singapore.

The overall computed tomography diagnostic yield was 21 per cent, with malignancy accounting for 63.6 per cent of diagnoses. Degree of vocal fold weakness was the only significant predictor of positive computed tomography findings (11.5 per cent in vocal fold paresis vs 29.1 per cent in vocal fold paralysis, p = 0.025). None of the patients with negative computed tomography findings went on to develop disease after a mean follow up of 14.3 months.

Computed tomography is a useful initial investigation for idiopathic unilateral vocal fold palsy, particularly in cases with vocal fold paralysis.

To investigate the value of narrow-band imaging training for differentiating between benign and malignant vocal fold leukoplakia.

Thirty cases of vocal fold leukoplakia were selected.

Narrow-band imaging endoscopy training had a significant positive effect on the specificity of the differential diagnosis of vocal fold leukoplakia. In addition, the consistency of diagnostic typing of vocal fold leukoplakia by narrow-band imaging improved to ‘moderate agreement’ following the combination of types I and II and the combination of types IV, V and VI in the typing of vocal fold leukoplakia.

The narrow-band imaging training course may improve the ability of laryngologists to diagnose vocal fold leukoplakia. The new endoscopic diagnostic classification by narrow-band imaging needs to be further simplified to facilitate clinical application.

There is growing evidence that the cells in the maculae flavae are tissue stem cells of the human vocal fold mucosa, and that the maculae flavae are a candidate for a stem cell niche. The role of microenvironment in the maculae flavae of the human vocal fold mucosa was investigated.

Anterior maculae flavae from six surgical specimens were cultured in a mesenchymal stem cell growth medium or a Dulbecco's modified Eagle's medium.

Using mesenchymal stem cell growth medium, the subcultured cells formed a colony-forming unit, and cell division reflected asymmetric self-renewal. This indicates that these cells are mesenchymal stem cells or stromal stem cells in the bone marrow. Using Dulbecco's modified Eagle's medium, the subcultured cells showed symmetric cell division without a colony-forming unit.

A proper microenvironment in the maculae flavae of the human vocal fold mucosa is necessary to be effective as a stem cell niche that maintains the stemness of the contained tissue stem cells.

There is growing evidence to suggest that cells in the maculae flavae are tissue stem cells of the human vocal fold and maculae flavae are a stem cell niche.

Three newborn vocal folds were investigated. Immunoreactivity to antibodies directed to cytokeratin, desmin, glial fibrillary acidic protein, vimentin, cluster of differentiation 34, cluster of differentiation 45, collagen type I, telomerase reverse transcriptase, SOX17 and stage-specific embryonic antigen 3 was investigated.

The cells in the newborn maculae flavae expressed haematopoietic markers (cluster of differentiation 34, cluster of differentiation 45) and collagen type I, which are the major makers of bone marrow derived circulating fibrocytes. The cells expressed epithelium, muscle, neural and mesenchymal cell associated proteins, and endodermal marker, indicating that they are undifferentiated and express proteins of all three germ layers. The cells also expressed stage-specific embryonic antigen 3 and telomerase reverse transcriptase.

The cells in the newborn maculae flavae are undifferentiated cells arising from the differentiation of bone marrow cells. The results of this study are consistent with the hypothesis that the cells in maculae flavae are tissue stem cells.

To introduce the application of confocal endomicroscopy during microlaryngoscopy, to enable intra-operative evaluation of human laryngeal epithelium.

A rigid endoscope was connected to the scanner head of a Heidelberg Retina Tomograph II confocal laser scanning system via an adapter. The endoscope was gently placed on the surface of a vocal fold through a laryngoscope during microlaryngoscopy.

The application of confocal endomicroscopy using a rigid endoscope enabled technical improvements (i.e. improved image quality, automatic volume scan, and reduced tissue pressure due to the presence of a perforation plate with central hole at the end of the endoscope) which permitted greater sensitivity and improved handling. Confocal endomicroscopy provided good quality, in vivo, en-face images and enabled an assessment of laryngeal epithelium volume.

This method enables the surgeon to monitor epithelial changes in pre-malignant lesions. The combination of confocal endomicroscopy together with optical coherence tomography (as a complementary technique that provides optical cross-sections) should be further explored in a formal clinicopathological study.

We report a novel bilateral suture lateralisation technique that allowed permanent tracheostomy decannulation in a patient with severe paradoxical vocal fold movement.

A 45-year-old woman presented to the accident and emergency department with worsening shortness of breath. Flexible nasoendoscopy revealed limited vocal fold abduction and an emergency tracheostomy was sited; this was subsequently changed to a long-term Silver Negus tube. Her tracheostomy care was complicated by discomfort and dislodgement. The diagnosis of paradoxical vocal fold movement was only made when the patient presented to our department. Cognitive behaviour therapy and botulinum toxin injection were tried without success. A right vocal fold lateralisation procedure was performed, which enabled temporary tracheostomy decannulation. A left vocal fold lateralisation procedure was subsequently performed and the patient was successfully decannulated, with significant improvement in quality of life.

Paradoxical vocal fold movement is a rare condition that is most commonly managed by biofeedback sessions, relaxation manoeuvres or botulinum toxin injection. However, in cases similar to ours in which these treatments are unsuccessful, we suggest a ‘last resort’ technique to manage this rare condition.

To introduce the use of optical coherence tomography with an operating microscope for intra-operative evaluation of the human larynx.

A specially equipped operating microscope with integrated spectral domain optical coherence tomography apparatus was used during microlaryngoscopy.

Technical improvements in optical coherence tomography equipment (e.g. pilot beam, variable focal distance, improved image quality and integration into an operating microscope) have enabled greater sensitivity and imaging speed and a non-contact approach. Spectral domain optical coherence tomography now enables a better correlation between optical coherence tomography images and histological findings. With this new technology, the precision of biopsy can be improved during microlaryngoscopy.

Use of this new optical coherence tomography technology, integrated into an operating microscope, enables the surgeon to define the biopsy site location and resection plane precisely, while the optical zoom of the operating microscope can be used over the complete range.

This study evaluated the role of botulinum toxin type A in the treatment of refractory laryngeal granulomas.

Retrospective clinical review at a tertiary care hospital. Seven patients with vocal process granulomas underwent percutaneous injection of botulinum toxin into both vocal folds, performed in an office setting. Total doses ranged from 10 to 25 U, divided between both vocal folds.

All patients experienced resolution of their granulomas over two to seven weeks. No patient developed aspiration pneumonia. All patients experienced hoarseness secondary to the injections, but voice quality returned to baseline in all patients as the toxin was degraded.

Botulinum toxin is safe and effective therapy in resolving vocal process granulomas in patients refractory to traditional therapy. The optimal treatment dose remains to be determined.

Percutaneous botulinum toxin injection is helpful in resolving laryngeal granulomas.