Stridor in asian infants: assessment and treatment.

Stridor is the main symptom of upper airway obstruction in infants. It can be congenital or acquired, acute or chronic. Pathologies can be located from the nose down to the trachea. Common causes include laryngomalacia, vocal cord palsy, subglottic stenosis, tracheal anomaly, laryngeal cleft, vascular and lymphatic malformation, laryngeal papillomas, craniofacial abnormalities and even head and neck tumours. In this paper, we will discuss our approach to infants with stridor including assessment with flexible and rigid endoscopy and treatments to various conditions in a tertiary centre. Causes of stridor in infants undergoing rigid laryngotracheobronchoscopy in Queen Mary Hospital, University of Hong Kong Medical Centre between 2005 and 2011 will be retrospectively reviewed. Treatments according to various conditions will be discussed. Successful management of these neonates requires accurate diagnosis, early intervention, and multidisciplinary care by ENT surgeons, paediatricians, and paediatric anaesthetists.

Manubrial resection and anterior mediastinal tracheostomy: friend or Foe?

OBJECTIVES/HYPOTHESIS: To review our experience with manubrial resection and anterior mediastinal tracheostomy and formulate operative guidelines to improve the surgical outcome. STUDY DESIGN: Retrospective study. METHODS: Between January 1980 and June 2010, we performed 38 manubrial resections. The indications of the procedure, reconstructive methods, and operative outcomes were analyzed. RESULTS: Fourteen patients had tumors of the hypopharynx/cervical esophagus, eight had parastomal recurrences of laryngeal tumor, four had recurrent esophageal tumors, four had postirradiation sarcoma, four suffered from subglottic/upper tracheal tumors, three had thyroid malignancy, and the remaining patient had tumor recurrence at the previous tracheostomy site. The hospital mortality rate was 5.3% due to bleeding from major vessel erosion. The mean length of the tracheal stump was 5.4 cm, of which 81.6% required relocation inferior to the innominate artery for construction of the mediastinal tracheostomy. Among the different reconstructive methods for the pharyngoesophageal defects, the anastomotic leakage rate was 17.6%, the majority of which required exteriorization followed by second stage reconstruction. The long-term tracheostomy stenosis rate was 47.4%, the risk of which was significantly increased by anastomotic leakage and necrosis of distal trachea. The use of a pectoralis major flap was shown to protect against this complication. The overall survival was 80.6% at 1 year and 55.6% at 5 years after surgery. CONCLUSIONS: With attention to operative details, manubrial resection and anterior mediastinal tracheostomy is a safe procedure with acceptable outcome. It should be performed when indicated to facilitate tumor resection in the cervicothoracic region.

Identification of pyruvate kinase type M2 as potential oncoprotein in squamous cell carcinoma of tongue through microRNA profiling.

MicroRNAs (miRNAs) are noncoding RNAs with specific regulatory role in gene expression. Recent reports suggested their involvement in human malignancies. Currently, there is no information concerning miRNA expression and functions in squamous cell carcinoma (SCC) of tongue. In this study, we evaluated the expression patterns of 156 mature miRNAs in tongue SCC using Taqman-based microRNA assays. Of these 156 miRNAs, miR-133a and miR-133b were significantly reduced in tongue SCC cells in comparison with the paired normal epithelial cells. Tongue SCC cell lines transfected with miR-133a and miR-133b precursors displayed reduction in proliferation rate. In addition, the number of apoptotic cells was increased in response to the introduction of precursors. Computational target gene prediction suggested that both miR-133a and miR-133b are targeting transcript of pyruvate kinase type M2 (PKM2), a potential oncogene in solid cancers. In tongue SCC cell lines, PKM2 expression was reduced in response to miR-133a and miR-133b precursors transfection. Immunohistochemical staining results of tongue SCC tissues suggested that PKM2 was overexpressed in tongue SCC and was associated with the downregulation of miR-133a and miR-133b. Our results suggested that aberrant reduction of miR-133a and miR-133b was associated with the dysregulation of PKM2 in SCC of tongue.