Multimodal imaging using optical coherence tomography and endolaryngeal ultrasonography in a new rabbit VX2 laryngeal cancer model.

BACKGROUND AND OBJECTIVE: Optical coherence tomography (OCT) provides ultrahigh-resolution imaging of tissues within a depth of a few millimeters, whereas ultrasonography provides good imaging further below the surface. We aimed to develop a minimally invasive rabbit model of VX2 laryngeal cancer, suitable for these two imaging modalities through a transoral approach. We also sought to study the utility of combined OCT and endolaryngeal ultrasonography (EUS) for evaluation of early and advanced laryngeal cancer, using this model. MATERIALS AND METHODS: VX2 tumor suspension was inoculated into the vocal folds of ten rabbits by injection through the trans-thyrohyoid membrane. The tumor model was characterized by rigid laryngoscopy and the tumor generation rate was 80% (8/10). Correlation between frequency-domain OCT and high-frequency EUS were used to visualize laryngeal tumors in the area of protruding mass formation in four rabbits, one week after injection (group A) and the remaining four rabbits two weeks after injection (group B). RESULTS: A small submucosal tumor was observed with rigid laryngoscopy in group A, and pathologic evaluation showed that the tumor was close to the basement membrane of the vocal fold mucosa, but had not invaded. OCT confirmed that the lining of the mucosa and basement membrane of the vocal fold was not broken, but the mucosa had thinned at the most elevated ridge. However, these lesions were not detected by EUS, and the overall shape of the tumor could not be clearly identified by EUS. A large tumor filling the laryngeal lumen was observed with rigid laryngoscopy in group B, and nearly the entire vocal fold, including the paraglottic space, was found to be involved on pathologic analysis. Distinguishing between normal structures and tumor was difficult using OCT; however, EUS confirmed the overall shape, size, and extent of the tumor, and the paraglottic space and thyroid cartilage were shown to be intact. CONCLUSIONS: This study is the first experimental trial, assessing the value of multimodal imaging using OCT and EUS in a rabbit VX2 laryngeal tumor model. Combining OCT and EUS helped to identify changes in laryngeal mucous membranes, and could potentially be used to identify laryngeal tumors and predict how tumors progress. This combined modality could help in determining tumor extent, assisting in diagnosis, and establishing a treatment plan for laryngeal cancer.

Trend of prevalence and characteristics of preserved ratio impaired spirometry (PRISm): Nationwide population-based survey between 2010 and 2019.

PURPOSE: This study aimed to evaluate the prevalence, trends, and factors of preserved ratio with impaired spirometry (PRISm) by using a nationally representative sample. PATIENTS AND METHODS: The datasets of the Korea National Health and Nutrition Examination Survey 2010-2019 were used: of total 32,949 participants aged ≥40 and no missing data on spirometry, 24,523 with normal, 4,623 with obstructive, and 3,803 with PRISm were identified. PRISm was defined as FEV1/FVC ≥70% and FEV1% of the predicted value (%pred) <80. PRISm-lower limit of normal (LLN) was defined when FEV1/FVC ≥LLN and FEV1

Time-Sequential Monitoring of the Early Mesothelial Reaction in the Pleura after Cryoinjury.

(1) Background: An early mesothelial reaction of the pleura, leading to fibrosis, has been reported in animals after chemical or heavy metal exposure. However, the visual monitoring of early time-sequential mesothelial reaction-associated cryoinjury has not been fully investigated. Therefore, this study aimed to evaluate and visualize the early mesothelial reactions seen following cryoinjury using rabbit pleura. (2) Methods: We monitored the early mesothelial reaction in rabbit pleurae after cryoinjury using optical coherence tomography (OCT), in real-time, which was then compared with pathological images. Due to the penetration limit of OCT, we made a thoracic window to image the parietal and visceral pleurae in vivo. We also used an innovative technique for capturing the microstructure in vivo, employing a computer-controlled intermittent iso-pressure breath hold to reduce respiratory motion, increasing the resolution of OCT. We organized three sample groups: the normal group, the sham group with just a thoracic window, and the experimental group with a thoracic window and cryotherapy. In the experimental group, localized cryoinjury was performed. The mesothelial cells at the level of pleura of the cryotherapy-injured site were visualized by OCT within the first 30 min and then again after 2 days at the same site. (3) Results: In the experimental group, focal thickening of the parietal pleura was observed at the site of cryoinjury using OCT after the first injury, and it was then confirmed pathologically as focal mesothelial cell proliferation. Two days after cryoinjury, diffuse mesothelial cell proliferation in the parietal pleura was noted on the reverse side around the cryoinjured site in the same rabbit. In the sham group, no pleural reaction was found. The OCT and pathological examinations revealed different patterns of mesothelial cell reactions between the parietal and visceral pleurae: the focal proliferation of mesothelial cells was found in the parietal pleura, while only a morphological change from flat cells to cuboidal cells and a thickened monolayer without proliferation of mesothelial cells were found in the visceral pleural. (4) Conclusions: An early mesothelial reaction occurs following cryoinjury to the parietal and visceral pleurae.

Serum Albumin and Disease Severity of Non-Cystic Fibrosis Bronchiectasis.

BACKGROUND: A clinical classification system has been developed to define the severity and predict the prognosis of subjects with non-cystic fibrosis (CF) bronchiectasis. We aimed to identify laboratory parameters that are correlated with the bronchiectasis severity index (BSI) and FACED score. METHODS: The medical records of 107 subjects with non-CF bronchiectasis for whom BSI and FACED scores could be calculated were retrospectively reviewed. The correlations between the laboratory parameters and BSI or FACED score were assessed, and multiple-linear regression analysis was performed to identify variables independently associated with BSI and FACED score. An additional subgroup analysis was performed according to sex. RESULTS: Among all of the enrolled subjects, 49 (45.8%) were male and 58 (54.2%) were female. The mean BSI and FACED scores were 9.43 ± 3.81 and 1.92 ± 1.59, respectively. The serum albumin level (r = -0.49), bilirubin level (r = -0.31), C-reactive protein level (r = 0.22), hemoglobin level (r = -0.2), and platelet/lymphocyte ratio (r = 0.31) were significantly correlated with BSI. Meanwhile, serum albumin (r = -0.37) and bilirubin level (r = -0.25) showed a significant correlation with the FACED score. Multiple-linear regression analysis showed that the serum bilirubin level was independently associated with BSI, and the serum albumin level was independently associated with both scoring systems. Subgroup analysis revealed that the level of uric acid was also a significant variable independently associated with the BSI in male bronchiectasis subjects. CONCLUSIONS: Several laboratory variables were identified as possible prognostic factors for non-CF bronchiectasis. Among them, the serum albumin level exhibited the strongest correlation and was identified as an independent variable associated with the BSI and FACED scores.

The successful treatment of refractory respiratory failure due to miliary tuberculosis: survival after prolonged extracorporeal membrane oxygenation support.

Acute respiratory distress syndrome (ARDS) has high morbidity and mortality. Although uncommon, pulmonary tuberculosis (TB) can cause ARDS in patients with extensive pulmonary parenchymal involvement. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is an accepted alternative option in refractory hypoxemic respiratory failure. It may normalize gas exchange and allow lung rest, avoiding ventilator induced lung injury. We report the case of a 44-year-old woman who developed ARDS secondary to pulmonary TB. Despite anti-TB treatment and mechanical ventilation, patient had persistent refractory hypoxemia. In order to prevent further lung injury, VV-ECMO support was performed for 73 days. Although the patient experienced several complications, patient was successfully managed on VV-ECMO. VV-ECMO support, in combination with anti-TB drugs, is a useful tool in the treatment of ARDS with refractory hypoxemia caused by miliary TB.

Neuron-specific enolase as a novel biomarker reflecting tuberculosis activity and treatment response.

BACKGROUND/AIMS: It is not clear which tests are indicative of the activity and severity of tuberculosis (TB). This study aimed to investigate the predictive value of neuron-specific enolase (NSE) and to determine the origin of NSE in TB patients. METHODS: A single-center retrospective analysis was conducted on newly diagnosed TB patients between January and December 2010. Patients were categorized into one of two disease groups (focal segmental or extensive) based on chest X-ray. Pre- and post-treatment NSE concentrations were evaluated. To determine the origin of serum NSE concentration, NSE staining was compared with macrophage-specific CD68 staining in lung tissues and with a tissue microarray using immunohistochemistry and immunofluorescence. RESULTS: A total of 60 newly diagnosed TB patients were analyzed. In TB patients, NSE serum concentration was significantly increased and NSE level decreased after treatment (p < 0.001). In proportion to serum high-sensitivity C-reactive protein concentration, the mean serum concentration of NSE in the extensive group (25.12 ng/mL) was significantly higher than that in the focal segmental group (20.23 ng/mL, p = 0.04). Immunohistochemical staining revealed a large number of macrophages that stained positively for both NSE and CD68 in TB tissues. In addition, NSE signals mostly co-localized with CD68 signals in the tissue microarray of TB patients. CONCLUSIONS: Our results suggest that NSE may be a practical parameter that can be used to monitor TB activity and treatment response. Elevated serum NSE level originates, at least in part, from macrophages in granulomatous lesions.

Successful treatment of a tracheal squamous cell carcinoma with a combination of cryoablation and photodynamic therapy.

Malignant tumors of the trachea are rare, and account for less than 0.1% of all malignancies. Because there are no guidelines based on randomized clinical trials, the choice of treatment modalities and optimal sequences have not yet been established. In most cases of malignant airway obstruction, a single modality is chosen as the treatment of choice for management, but complete ablation becomes increasingly problematic with minimal residual lesions that require additional treatment. There were few case reports of the combined use of cryoablation and photodynamic therapy to treat tracheal cancer. Therefore, we present our experience of successful tracheal cancer treatment using this combination therapy. A bronchoscopic complete regression was obtained using these two modalities, and the procedures proved to be a safe and effective treatment option based on a one-year follow-up.

Respiratory review of 2012: bronchoscopic innovations and advances.

Recent advances in bronchoscopy have led to changes in clinical diagnostics and therapeutics in pulmonary medicine. In diagnostic bronchoscopy, there have also been new developments in endobronchial ultrasound technology which may be incorporated into clinical practice in the near future. Functional bronchoscopy, which evaluates information such as airway pressure, airflow, or gas exchange, suggests promising clinical advances in the near future. In therapeutic bronchoscopy, bronchoscopic volume reduction is a novel approach for the treatment of severe emphysema. In this review, seven recently published articles representing current advances in bronchoscopy are summarized and discussed.