Hyo Jin Chung

Level of secreted HMGB1 correlates with severity of inflammation in chronic rhinosinusitis

High mobility group box 1 (HMGB1) protein is a chromatin protein that functions as a proinflammatory cytokine when secreted in response to inflammatory stimuli. The purpose of this study was to determine the relationship between the HMGB1 level in nasal secretions and the severity of inflammation in chronic rhinosinusitis.

Mitochondrial reactive oxygen species modulate innate immune response to influenza A virus in human nasal epithelium.

The innate immune system of the nasal epithelium serves as a first line of defense against invading respiratory viruses including influenza A virus (IAV). Recently, it was verified that interferon (IFN)-related immune responses play a critical role in local antiviral innate immunity. Reactive oxygen species (ROS) generation by exogenous pathogens has also been demonstrated in respiratory epithelial cells and modulation of ROS has been reported to be important for respiratory virus-induced innate immune mechanisms. Passage-2 normal human nasal epithelial (NHNE) cells were inoculated with IAV (WS/33, H1N1) to assess the sources of IAV-induced ROS and the relationship between ROS and IFN-related innate immune responses. Both STAT1 and STAT2 phosphorylation and the mRNA levels of IFN-stimulated genes, including Mx1, 2,5-OAS1, IFIT1, and CXCL10, were induced after IAV infection up to three days post infection. Similarly, we observed that mitochondrial ROS generation increased maximally at 2 days after IAV infection. After suppression of mitochondrial ROS generation, IAV-induced phosphorylation of STAT and mRNA levels of IFN-stimulated genes were attenuated and actually, viral titers of IAV were significantly higher in cases with scavenging ROS. Our findings suggest that mitochondrial ROS might be responsible for controlling IAV infection and may be potential sources of ROS generation, which is required to initiate an innate immune response in NHNE cells.

Improved outcomes after low-concentration hypochlorous acid nasal irrigation in pediatric chronic sinusitis

We aimed to evaluate the effectiveness of low‐concentration hypochlorous acid (HOCl) nasal irrigation compared to isotonic normal saline for pediatric chronic rhinosinusitis.

Characteristics, management of the neck, and oncological outcomes of malignant minor salivary gland tumours in the oral and sinonasal regions

The aim of this study was to evaluate the characteristics of malignant tumours of the minor salivary glands in the oral and sinonasal regions, to make sure that the neck was managed correctly, and to identify oncological outcomes, retrospectively, at a single hospital. A total of 60 patients were reviewed. Forty-nine patients had intraoral lesions and 11 had sinonasal lesions. Of the 60 patients, 28 had stage I to II malignant tumours, and 32 had stage III to IV tumours. Treatment was almost exclusively surgical. One of the 16 patients whose nodes were clinically clear had an elective neck dissection. Adjuvant radiotherapy was given if indicated. The mean follow-up period was 52 months (range 13-190). Sinonasal lesions were all advanced T-stage at diagnosis, had more invaded resection margins, and a higher local recurrence rate than intraoral lesions. There was no regional recurrence in those patients whose nodes were clinically invaded and who had therapeutic neck dissection, or in the patient whose nodes were clinically clear and who had an elective neck dissection. Occult metastases developed exclusively in adenoid cystic carcinomas (ACC), the rate of which was 4/16. Regional recurrence developed in 4 patients who had never had elective treatment to the neck 2 of whom mixed pattern ACC and 2 who had low grade mucoepidermoid carcinomas (MEC). The overall survival was 90% at 2 years, 77% at 5 years, and 74% at 10 years. Sinonasal minor salivary gland tumours require careful follow-up because resection margins are more likely to be invaded by tumour, and they have a higher local recurrence rate than intraoral lesions. Elective neck dissection is needed, particularly for MEC and also to prevent regional recurrence in ACC.

Robotic nasopharyngectomy via combined endonasal and transantral port: A preliminary cadaveric study

The objective of this study was to determine the potential role of a surgical robotic system in nasopharyngeal surgery using bilateral transantral or combined endonasal/transantral port.

Tongue Volume Influences Lowest Oxygen Saturation but Not Apnea-Hypopnea Index in Obstructive Sleep Apnea

Objectives The aim of this study was to identify correlations between sleep apnea severity and tongue volume or posterior airway space measured via three-dimensional reconstruction of volumetric computerized tomography (CT) images in patients with obstructive sleep apnea (OSA) for use in predicting OSA severity and in surgical treatment. We also assessed associations between tongue volume and Mallampati score. Methods Snoring/OSA male patients (n = 64) who underwent polysomnography, cephalometry, and CT scans were enrolled in this retrospective study. OSA was diagnosed when the apnea-hypopnea index (AHI) was greater than 5 (mild 5–14; moderate 15–29; severe>30). The patients were also categorized into the normal-mild group (n = 22) and the moderate-severe group (n = 42). Using volumetric CT images with the three-dimensional reconstruction technique, the volume of the tongue, posterior airway space volume, and intra-mandibular space were measured. The volumes, polysomnographic parameters, and physical examination findings were compared, and independent factors that are related to OSA were analysed. Results No associations between tongue volume or posterior airway space and the AHI were observed. However, multivariate linear analyses showed that tongue volume had significantly negative association with lowest O2 saturation (r = 0.365, p = 0.027). High BMI was related to an increase in tongue volume. Modified Mallampati scores showed borderline significant positive correlations with absolute tongue volume (r = 0.251, p = 0.046) and standardized tongue volume (absolute tongue volume / intramandibular area; r = 0.266, p = 0.034). Between the normal-mild and moderate-severe groups, absolute tongue volumes were not different, although the standardized tongue volume in the moderate-severe group was significantly higher. Conclusion Absolute tongue volume showed stronger associations with lowest O2 saturation during sleep than with the severity of AHI. We also found that high BMI was a relevant factor for an increase in absolute tongue volume and modified Mallampati grading was a useful physical examination to predict tongue size.

Endoscope-guided coblator tongue base resection using an endoscope-holding system for obstructive sleep apnea

Multilevel obstruction in obstructive sleep apnea commonly includes retroglossal obstruction. To improve surgical success rates, tongue volume reduction with posterior midline glossectomy and/or lingual tonsillectomy is widely performed.

Comparison of calcium alginate and carboxymethyl cellulose for nasal packing after endoscopic sinus surgery: a prospective, randomised, controlled single‐blinded trial

Calcium alginate is a biodegradable gel‐transforming agent widely used for nasal packing. It can reduce pain and improve comfort. However, few randomised controlled trials have compared the efficacy of calcium alginate nasal packing with that of other biodegradable gel‐transforming materials.

Predictors of success in combination of tongue base resection and lateral pharyngoplasty for obstructive sleep apnea

The base of the tongue has been recognized as a significant site of obstruction in patients with obstructive sleep apnea (OSA). Our aim was to determine the independent predictors of surgical success in tongue base resection combined with lateral pharyngoplasty for OSA. Thirty-one OSA patients who underwent endoscopie-guided coblator or transoral robotic tongue base resection in combination with lateral pharyngoplasty for the treatment of retroglossal obstruction between March 2012 and December 2015 were enrolled in this study. Retroglossal obstruction was identified by preoperative nasopharyngoscopy with drug-induced sleep endoscopy and/or Müller’s maneuver in supine position. Patients were divided into success and failure groups according to surgical outcome (postoperative apnea–hypopnea index (AHI) less than 20 and reduction more than 50% in baseline AHI). Physical profile, polysomnography, cephalometry parameters, and drug-induced sleep endoscopy and/or Müller’s maneuver findings were compared between the two groups. Tonsil grade (p = 0.002), lateral oropharyngeal wall collapse on Müller’s maneuver (p = 0.002), and AHI during rapid eye movement (REM AHI) (p = 0.038) were significantly higher in the success group than in the failure group. Tongue base collapse was more evident in the failure group than in the success group when patients open their mouth. (p = 0.037) Bigger tonsil size and higher REM AHI are favorable predictive factors, even in multilevel surgery such as tongue base resection, whereas tongue base collapse during mouth opening may be an unfavorable predictive factor.

Lowest oxyhemoglobin saturation may be an independent factor influencing auditory function in severe obstructive sleep apnea

STUDY OBJECTIVES The aims of this study were to determine if a correlation exists between the level of hypoxia induced by severe obstructive sleep apnea syndrome (OSAS) and the level of auditory dysfunction when verifying such a relationship using polysomnography (PSG). METHODS A retrospective review of 41 patients with severe OSAS was performed. Independent risk factors for hearing impairment included parameters of PSG, which were analyzed in two hearing groups at a level ≥ 40 decibels (dB). RESULTS Oxyhemoglobin saturation, especially the lowest oxyhemoglobin saturation level, showed lower thresholds in the hearing impairment group than in the control group (p = 0.039 at NREM stage; p = 0.029 at REM stage; p = 0.001 at total sleep stage). After adjusting for other risk factors, the sole variable that remained significant was lowest oxyhemoglobin saturation (total; p = 0.046). In the correlation analysis, a decreasing lowest oxyhemoglobin saturation (from all subjects, n = 41) correlated with a greater mean hearing threshold (R(2) = 0.297; p < 0.001). CONCLUSION Our results indicated that lowest oxyhemoglobin saturation in PSG is the only variable correlated with the hearing threshold. This finding could be predictive of possible hearing alternation in patients with severe OSAS. COMMENTARY A commentary on this article appears in this issue on page 641.