Replication of SARS-CoV-2 Omicron BA.2 variant in ex vivo cultures of the human upper and lower respiratory tract.

BACKGROUND: The Omicron BA.2 sublineage has replaced BA.1 worldwide and has comparable levels of immune evasion to BA.1. These observations suggest that the increased transmissibility of BA.2 cannot be explained by the antibody evasion. METHODS: Here, we characterized the replication competence and respiratory tissue tropism of three Omicron variants (BA.1, BA.1.1, BA.2), and compared these with the wild-type virus and Delta variant, in human nasal, bronchial and lung tissues cultured ex vivo. FINDINGS: BA.2 replicated more efficiently in nasal and bronchial tissues at 33°C than wild-type, Delta and BA.1. Both BA.2 and BA.1 had higher replication competence than wild-type and Delta viruses in bronchial tissues at 37°C. BA.1, BA.1.1 and BA.2 replicated at a lower level in lung parenchymal tissues compared to wild-type and Delta viruses. INTERPRETATION: Higher replication competence of Omicron BA.2 in the human upper airway at 33°C than BA.1 may be one of the reasons to explain the current advantage of BA.2 over BA.1. A lower replication level of the tested Omicron variants in human lung tissues is in line with the clinical manifestations of decreased disease severity of patients infected with the Omicron strains compared with other ancestral strains. FUNDING: This work was supported by US National Institute of Allergy and Infectious Diseases and the Theme-Based Research Scheme under University Grants Committee of Hong Kong Special Administrative Region, China.

Long-term results of robotic-assisted nasopharyngectomy for recurrent nasopharyngeal carcinoma.

BACKGROUND: We have previously reported our early experience in robotic-assisted nasopharyngectomy. The current case series is a report of our experience in 33 robotic-assisted nasopharyngectomy. METHODS: Prospective series of patients who underwent robotic-assisted nasopharyngectomy for local recurrent nasopharyngeal carcinoma from January 2010 to March 2019. RESULTS: Thirty-one patients underwent robotic-assisted nasopharyngectomy with two additional second procedure for positive margin. Median age is 55 years (29-85). Twenty-five patients had rT1 disease and six patients had tumor invaded sphenoid floor (rT3). Median operative time was 227 min and median blood loss was 200 ml. The median follow-up period for all patients were 38 months. Four patients had local recurrence. Five-year local control rate, overall survival, and disease-free survival are 85.1%, 55.7%, and 69.1%, respectively. CONCLUSION: Robotic-assisted nasopharyngectomy for recurrent nasopharyngectomy was showed to have a high local control rate. The operating time was comparable to open surgery.

Long-term Complications of Palate Surgery: A Multicenter Study of 217 Patients.

OBJECTIVES/HYPOTHESIS: To investigate long-term complications of newer reconstructive palate surgery techniques. STUDY DESIGN: Retrospective case-series analysis. METHODS: Retrospective six-country clinical study of OSA patients who had nose and palate surgery. RESULTS: There were 217 patients, mean age = 43.9 ± 12.5 years, mean body mass index = 25.9 ± 4.7, mean preoperative apnea-hypopnea index [AHI] = 30.5 ± 19.1, follow-up 41.3 months. A total of 217 palatal procedures were performed, including 50 expansion sphincter pharyngoplasties (ESP), 34 functional expansion pharyngoplasties (FEP), 40 barbed reposition pharyngoplasties (BRP), 64 modified uvulopalatopharyngoplasties (mUPPP), 11 uvulopalatal flap procedures (UPF), nine suspension pharyngoplasties (SP), eight relocation pharyngoplasties (RP), and one z-pharyngoplasty (ZPP). Complications included were constant and/or felt twice per week; dry throat (7.8%), throat lump feeling (11.5%), throat phlegm (10.1%), throat scar feeling (3.7%), and difficulty swallowing (0.5%). Of the 17 patients who had a dry throat complaint, two were constant (one SP, one RP), 15 were occasional (10 mUPPP, three SP, two BRP). Of the 25 patients with the throat lump feeling, four were constant (three RP, one ZPP), 21 were occasional (10 mUPPP, five SP, five UPF, one BRP). Of the 22 patients with the throat phlegm feeling, four were constant (two SP, two RP), 18 were occasional (10 mUPPP, four BRP, two FEP, two SP). Of the eight patients with throat scar feeling, eight were occasional (four SP, two mUPPP, one FEP, one RP), none were constant. One patient had difficulty swallowing (RP procedure). There was no velopharyngeal incompetence, taste disturbance, nor voice change. Highest symptom complaints were mUPPP, SP, and RP, whereas the lowest symptom complaint was ESP. CONCLUSIONS: Newer palatal techniques have shown to have less long-term complications compared to the older ablative techniques. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2281-2284, 2020.