Cartilage Rings Research Articles

In Vitro Cartilage Regeneration with a Three-Dimensional Polyglycolic Acid (PGA) Implant in a Bovine Cartilage Punch Model.

Resorbable polyglycolic acid (PGA) chondrocyte grafts are clinically established for human articular cartilage defects. Long-term implant performance was addressed in a standardized in vitro model. PGA implants (+/− bovine chondrocytes) were placed inside cartilage rings punched out of bovine femoral trochleas (outer Ø 6 mm; inner defect Ø 2 mm) and cultured for 84 days (12 weeks). Cartilage/PGA hybrids were subsequently analyzed by histology (hematoxylin/eosin; safranin O), immunohistochemistry (aggrecan, collagens 1 and 2), protein assays, quantitative real-time polymerase chain reactions, and implant push-out force measurements. Cartilage/PGA hybrids remained vital with intact matrix until 12 weeks, limited loss of proteoglycans from “host” cartilage or cartilage–PGA interface, and progressively diminishing release of proteoglycans into the supernatant. By contrast, the collagen 2 content in cartilage and cartilage–PGA interface remained approximately constant during culture (with only little collagen 1). Both implants (+/− cells) displayed implant colonization and progressively increased aggrecan and collagen 2 mRNA, but significantly decreased push-out forces over time. Cell-loaded PGA showed significantly accelerated cell colonization and significantly extended deposition of aggrecan. Augmented chondrogenic differentiation in PGA and cartilage/PGA-interface for up to 84 days suggests initial cartilage regeneration. Due to the PGA resorbability, however, the model exhibits limitations in assessing the “lateral implant bonding”.

Partial Decellularization for Segmental Tracheal Scaffold Tissue Engineering: A Preliminary Study in Rabbits.

In this study, we developed a new procedure for the rapid partial decellularization of the harvested trachea. Partial decellularization was performed using a combination of detergent and sonication to completely remove the epithelial layers outside of the cartilage ring. The post-decellularized tracheal segments were assessed with vital staining, which showed that the core cartilage cells remarkably remained intact while the cells outside of the cartilage were no longer viable. The ability of the decellularized tracheal segments to evade immune rejection was evaluated through heterotopic implantation of the segments into the chest muscle of rabbits without any immunosuppressive therapy, which demonstrated no evidence of severe rejection or tissue necrosis under H&E staining, as well as the mechanical stability under stress-pressure testing. Finally, orthotopic transplantation of partially decellularized trachea with no immunosuppression treatment resulted in 2 months of survival in two rabbits and one long-term survival (2 years) in one rabbit. Through evaluations of posttransplantation histology and endoscopy, we confirmed that our partial decellularization method could be a potential method of producing low-immunogenic cartilage scaffolds with viable, functional core cartilage cells that can achieve long-term survival after in vivo transplantation.

AB124. SOH21AS106. Balloon dilatation of subglottic stenosis related to granulomatosis with polyangiitis-long term follow up of four patients and their outcomes

Background: Subglottic stenosis is a well-known potentially life-threatening presentation of granulomatosis with polyangiitis (GPA). Circumferential scarring and critical narrowing of the airway at the level of cricoid cartilage and/or upper tracheal rings appears in 10–16% of patients with GPA. Symptoms range from cough and shortness of breath to life-threatening dyspnoea with stridor. Majority of patients need tracheostomy at the moment of diagnosis. Surgical treatment consists of endoscopic surgery, complex resection of the stenotic segment followed by reconstruction and stenting. Surgical therapy usually has to be repeated due to restenosis of the airway despite ongoing medical treatment. Endoscopic balloon dilatation is a procedure of choice in our institution in a long term management of those patients with good postoperative results. We present four patients with a long history of GPA complicated by airway obstruction and their management.

Microscopic and morphometric study in trachea and lungs of adult Iraqi pigeon (Columba livia)

The study applied light to investigate the microscopic and macroscopic results of the trachea and lungs in adult Iraqi pigeons (Columba livia). Age of the pigeons was (8-12) months. Our study was carried out 12 adult pigeons. These pigeons were supplement from local market of Baghdad city, Iraq. The morphological study of adult pigeon observed that the trachea included long tube of cartilaginous structure is extended from larynx until enters to left and right lungs with runs alongside the esophagus inside the thoracic cavity. This trachea was characterized by flexible bulk, non folded ring and numerous series of thin complete cartilage ring. The statistics analysis was used for grossly morphological organs, where was number of thin cartilage rings average range (67-70) complete rings. The study used the morphometric measurements for length of the trachea was (10±0.6) cm. and diameter of ring lumen about (0.6±0.12) cm.. Either the lungs results of adult pigeons were showed pink color, spongy mass and trapezium- like. The lungs were located inside thoracic cavity and connected by ribs with appearance costal impressions on the dorsal surface of the lungs. The morphometric study were included statistic analysis of lungs, weight of lungs were about (6±0.01) mg. and length was ( 3.32±0.2) cm. . Histological study showed tracheal ring of Columba livia was thin complete. The study observed histological layers included tunica mucosa, submucosa and adventitia, the first portion of mucosa is called epithelia, it’s characteristic by ciliated pseudostratified columnar epithelium with goblet cells, lamina properia has loose connective tissue which it is rich blood vessels. Submucosa is a beneath layer of mucosa, and contains tracheal cartilaginous tube, large blood vessels and numerous seromucous glands. Pigeon’s lungs were formed than parabronchi, it’s located in center of pulmonary lobule and separated by septa (connective tissue) named interlobular wall, which is originated from secondary bronchi and united with other. The epithelia lined the parabronchi by simple squeomous cells to help gaseous exchange inside the lungs .

Biomechanical strength dependence on mammalian airway length.

BackgroundThe trachea is the uppermost respiratory airway element connecting the larynx to the bronchi Airway reconstructions in humans are often developed from animal models but there is limited knowledge comparing tracheal biomechanics between species. We aimed to assess the structure and biomechanics of porcine, canine, caprine and human airways.MethodsTracheas from pigs (n=15), goats (n=9) and canines (n=9) were divided into three groups (4, 6 and 8-ringswhile human left principal brochi (n=12) were divided into two groups (3and-rings). Airway structures were compared using histology and scanning electron microscopy. Biomechanical properties were measured subjecting samples to uniaxial tension and compression, recording the elastic modulus and (tensile and compressive) strengths.ResultsThe structures of animal tracheal and human bronchia appeared similar. Biomechanical testing revealed that the elastic modulus of 8-ring tracheas was 1,190.48±363.68, 2,572.00±608.19 and 1,771.27±145.54 kPa, for porcine, canine and caprine samples, respectively, while corresponding tensile strengths were 437.63±191.41, 808.38±223.48 and 445.76±44.00 kPa. Comparable measures of anterior-posterior (A-P) compression strengths were 7.94±0.82, 7.54±0.07 and 8.10±1.87 N, respectively, whereas lateral compression strengths were 8.75±0.82, 14.55±2.29 and 11.12±0.40 N. Compression testing of human samples showed significant differences (P<0.05) between the 3-ring (A-P, 1.06±0.02 N; lateral, 0.55±0.06 N) and 5-ring groups (A-P, 1.08±0.64 N; lateral, 2.32±1.95 N).ConclusionsThe tensile and compressive strengths of mammalian airways show positive correlations with the cartilage ring number (length). On the basis of structural and biomechanical comparisons, porcine, canine and caprine species appear suitable models for the study of airway reconstruction in human.

Mechanical properties of de-epithelialized tracheal allografts.

BackgroundMany studies have shown that mucosa-treated tracheas can be used for allotransplantation without the use of immunosuppressants. However, no literature has reported whether the transplanted trachea has normal biomechanics. In this study, fresh dog trachea was used as a control to determine the mechanical properties of allograft trachea after mucous membrane removal.MethodsCervical tracheas (~10 cm in length, consisting of the cartilage rings down to the tracheal carina) and the surrounding connective tissues were removed from 20 mixed-breed dogs and then divided into 4 groups with 5 samples in each group. The groups were defined as follows: group A, fresh canine tracheas without any treatment; group B, canine tracheas after sodium dodecyl sulphate (SDS) de-epithelialization; group C, canine tracheas implanted into the dorsal fascia of beagle dogs for 1 month after SDS de-epithelialization; group D, canine tracheas implanted into the dorsal fascia of beagle dogs for 6 months after SDS de-epithelialization. All heterotopically implanted beagle dogs were free of any immunosuppressive treatment. Uniaxial tensile (n=20) and compressive (n=20) experiments were performed on the 4 groups of trachea using a universal testing machine; the tensile load was recorded at 150% of the original tracheal length (50% displacement), and the compressive load was recorded at 50% of the initial anteroposterior diameter (50% displacement). The average difference in tensile and compressive loads between groups was compared by analysis of variance.ResultsNo significant difference was found in the mean compressive strength among groups (group A =2.38±0.87 N, group B =3.33±1.03 N, group C =5.39±2.44 N, group D =3.04±2.12 N; P=0.07 for all groups). The mean tensile strength of group C was 9.68±0.86 N, resulting in a significant difference in tensile strength compared to group A (22.51±3.91 N) and B (24.24±7.46 N) (P<0.001). No significant difference in tensile strength was observed among groups A, B, and D.ConclusionsThe de-epithelialized trachea showed no significant change in mechanical properties after 6 months of implantation.

Reconstruction of the carina using bronchial autograft: an alternative approach.

We report successful engraftment by autologous transplantation of the bronchial wall of the resected specimen in extensive tracheobronchial resection with left pneumonectomy. Since the adenoid cystic carcinoma had spread beyond the carina to the right bronchus, we resected three rings of tracheal cartilage and three rings of left main bronchus cartilage. Reconstruction was performed using the bronchial wall of the resected specimen to relieve tension on the anastomosis. No stricture or recurrence was observed four years after the operation. Further research relating to maximization of blood flow to the reconstructed tissue based on engraftment area and shape is required.

Histological features of complete tracheal rings in congenital tracheal stenosis.

Congenital tracheal stenosis is a disease in which complete tracheal cartilage rings (CTCR) cause airway narrowing. Although tracheal cartilage malformation has been suggested as a cause of CTCR, no histological studies have been performed. Here, we report a comparison of the tissues from CTCR and normal tracheal cartilage. Thirty-one infants who underwent slide tracheoplasty at our institution from May 2016 to August 2019 were included. Tissues from ten autopsy cases without tracheal lesions were used as controls. The survey items were tracheal cartilage cell density, cartilage thickness, and chondrocyte findings. The median cartilage cell density from cases was 23/125 × 125µm2 and from controls was 23.5/125 × 125µm2 (p = 0.90). The median cartilage thickness from cases was 689µm and from controls was 840µm (p = 0.11). Comparing the ventral and dorsal sides of the CTCR tissues, the cell density was significantly different (median ventral 23/125 × 125 µm2; median dorsal 19.5/125 × 125µm2; p = 0.034). There were no significant findings in the chondrocytes of the CTCR tissues. CTCR tissues did not differ in cartilage density and thickness from normal tracheal cartilage.

WILLIAMS-CAMPBELL SYNDROME: A RARE CAUSE OF CYSTIC LUNG DISEASE

SESSION TITLE: Medical Student/Resident Diffuse Lung Disease SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Williams-Campbell syndrome (WCS), also known as bronchomalacia, is a rare form of bronchiectasis that develops due to markedly diminished or absent cartilage around the sub-segmental bronchi, resulting in dilation of the subsequent bronchi. Affected patients will have a normal trachea and central bronchi caliber with cystic bronchiectasis affecting the fourth to sixth-order bronchi. Although WCS has been best described in children with recurrent pneumonia and broncho-obstructive symptoms, there have been recent descriptions in adults due to delayed diagnosis [1]. CASE PRESENTATION: A 69-year-old non-smoking female with a history of severe bronchiectasis and chronic hypoxemic respiratory failure presented with complaints of progressive dyspnea and productive cough. Her respiratory symptoms started about 20 years ago with no clear inciting etiology and have gradually worsened. Chest x-ray (CXR) at that time showed multiple areas of cystic degeneration (Fig. 1). She was transferred to us after being diagnosed with acute on chronic hypoxic respiratory failure from rhinovirus infection. Physical examination revealed bilateral coarse crackles with rhonchi. Arterial blood gas showed hypoxic and hypercapnic respiratory failure. CXR was significant for cystic changes with bilateral pulmonary infiltrates and a small right-sided effusion. Computed tomographic (CT) scan of the chest showed cystic lesions with patchy infiltrates suggestive of bronchopneumonia (Fig. 2). On hospital day 2, she developed copious hemoptysis requiring transfusion of packed red blood cells. Her respiratory distress was managed conservatively with non-invasive mechanical ventilation. Bronchoscopy was not pursued due to her DNI status and an increased risk of ventilator dependence after the procedure. When her overall clinical condition improved after steroid and antibiotic treatment, she was discharged with home health therapy. DISCUSSION: WCS is a rare cause of congenital bronchiectasis usually diagnosed in childhood when patients present with recurrent pneumonia, cough and wheezing. However, adults have been diagnosed with WCS later in life because of either a subclinical presentation or an acquired form secondary to adenovirus exists [1]. Multi-splice spiral CT and CT bronchoscopy can be used to diagnose WCS. A lack of cartilage rings, as determined by an absence of ring impressions, will be seen on imaging [1]. Treatment is generally supportive with prophylactic antibiotics, inhaled corticosteroids, and exercise or inspiratory muscle training [3]. CONCLUSIONS: To prevent a delayed diagnosis, William-Campbell Syndrome should be considered in adults presenting with cystic lung disease with bronchiectasis, productive cough, and recurrent infections. Reference #1: Aldave AP, Saliski DW. The clinical manifestations, diagnosis and management of Williams-Campbell syndrome. North American Journal of Medical Sciences. 2014 Sep;6(9):429-432. Reference #2: Shoemark A, Ozerovitch L, Wilson R. Aetiology in adult patients with bronchiectasis. Respiratory Medicine. 2007 Jun 1;101(6):1163-70. Reference #3: ten Hacken NH, van der Molen T. Bronchiectasis. BMJ. 2010 Jul 14;341:c2766. DISCLOSURES: My spouse/partner as a Consultant relationship with Abbvie Please note: $1-$1000 Added 05/27/2020 by Ebtesam Islam, source=Web Response, value=Consulting fee No relevant relationships by Kenneth Iwuji, source=Web Response No relevant relationships by Lisa Saa, source=Web Response

Technique of laryngotracheal resection in subglottic stenosis.

Cervical stenosis of the trachea caused by tracheotomy, tumor or induced by inflammatory disease can be treated by resection and anastomosis with good early and long-term results. Involvement of the ring cartilage makes the procedure technical demanding and increases the risk of morbidity. We describe our technique of laryngotracheal resection and reconstruction and compare the perioperative results with standard trachea resection. Between January 2005 and September 2018, we performed 92 standard cervical tracheal resections and 50 laryngotracheal resection including 6 procedures with widening of the ring cartilage. The resections were realized by direct anastomosis using dorsal flaps and/or interposition of rib cartilage in the posterior part of the ring cartilage. In one case intraoperative tracheotomy and intralaryngeal stenting was used. Patient records have been analyzed for perioperative data retrospectively. The main cause for stenosis or defect of the trachea and operation is preceding tracheotomy. Idiopathic stenosis, tumors and subglottic stenosis in Wegener disease are less common. Healing of the anastomosis was not disturbed in any patient. In two patients, bronchoscopic resection of granulation tissue was necessary. Tracheotomy in the course of treatment for intralaryngeal swelling or recurrent nerve palsy was necessary in 3 patients including one intraoperative tracheotomy for glottic stenting. Postoperative tracheostomy was closed in all patients within 3 months. Pulmonary complications and persistent recurrent nerve palsy occurred in 4 and 2 of the patients, respectively. Two patients died of pulmonary complications. The laryngotracheal resection is a relevant part of cervical tracheal surgery. It can be performed without significant elevated morbidity and is able to restore lung function and quality of voice.

Morphological features of lower respiratory tract of nine-banded armadillo (Dasypus novemcinctus, Linnaeus, 1758).

The nine-banded armadillo (Dasypus novemcinctus) is a mammal of the Xenarthra Superorder, which inhabits Central, South and North America. Few morphological descriptions are observed in this species, including the respiratory tract; therefore, the objective of this study was to describe morphologically the lower respiratory tract of the nine-banded armadillo. Five animals were dissected, and the macroscopic and microscopic aspects were analysed. In the anatomical analysis, the perfusion technique was performed with vinyl acetate and the fragments of tissue from respiratory organs (trachea, bronchi, bronchioles and pulmonary lobes) were stained with haematoxylin-eosin for visualization under optical microscopy. Containing about 30 cartilage rings, the trachea is lined internally with ciliated pseudostratified epithelial tissue. The lungs are subdivided into lobes by deep interlobar fissures, with two lobes in the right lung and three lobes in the left lung. Microscopically, the primary, secondary and tertiary bronchi have non-ciliated pseudostratified epithelium with goblet cells. It was found that macro- and microscopically the respiratory tract of this species is similar to existing xenarthras and other excavator animals. These data provide subsidies for the clinic and preservation of this species.

Biomimetic Trachea Regeneration Using a Modular Ring Strategy Based on Poly(Sebacoyl Diglyceride)/Polycaprolactone for Segmental Trachea Defect Repair

AbstractThe lack of a biomimetic tracheal substitute featured with cartilage ring/vascularized connective tissue alternate structure (CVCAS) has significantly retarded a clinical breakthrough of tissue‐engineered trachea in repairing extensive tracheal lesions. Herein, a novel modular strategy based on cartilage rings and biomaterial rings is used to generate a biomimetic trachea with CVCAS. Poly(sebacoyl diglyceride) and polycaprolactone (PCL) (PSeD/PCL) are blended to fabricate a porous scaffold with satisfactory mechanical properties, biodegradability, and biocompatibility. A cartilage ring is engineered in vitro using ring‐shaped PSeD/PCL scaffold loaded with chondrocytes and cartilage tube is generated in vivo through the fusion of multiple modular cartilage rings. More importantly, biomimetic tracheas with CVCAS are successfully fabricated in vivo through alternately stacked cartilage rings and PSeD/PCL rings on a silicon tube. Notably, the engineered biomimetic trachea exhibits not only a bionic structure but also superior mechanical properties compared with the native rabbit trachea. Finally, segmental tracheal defects in rabbits are repaired by transplanting the biomimetic trachea with pedicled muscular flaps. The biomimetic trachea establishes stable blood supply and provided sufficient mechanical strength and biological function similar to those of native trachea. This work represents the first successful regeneration of biomimetic trachea with CVCAS and a promising approach for clinical application.

Tracheobronchopathia Osteochondroplastica: A Case Report

Introduction: Tracheobronchopathia Osteochondroplastica (TPO) is a rare disease that is characterized by bony canals located on the cartilage ring. We here report one case of tracheobronchopathia osteochondroplastica Case Report: A 64-year-old female patient was admitted to the hospital with a productive cough, sputum, and fever for ten days. Her chest CT scan showed mild thickening and irregularity associated with calcification in the trachea wall and main bronchus. The patient had rheumatoid arthritis, and after consultation with a rheumatologist, she received pneumonia treatment and then underwent bronchoscopy. Conclusion: TPO is a rare, benign disease with slow progression. Physicians should be aware of TPO and should consider it in patients with chronic cough and respiratory infections.

Chondroitinase ABC Enhances Integration of Self-Assembled Articular Cartilage, but Its Dosage Needs to Be Moderated Based on Neocartilage Maturity.

To enhance the in vitro integration of self-assembled articular cartilage to native articular cartilage using chondroitinase ABC. To examine the hypothesis that chondroitinase ABC (C-ABC) integration treatment (C-ABCint) would enhance integration of neocartilage of different maturity levels, this study was conducted in 2 phases. In phase I, the impact on integration of 2 treatments, TCL (TGF-β1, C-ABC, and lysyl oxidase like 2) and C-ABCint, was examined via a 2-factor, full factorial design. In phase II, construct maturity (2 levels) and C-ABCint concentration (3 levels) were the factors in a full factorial design to determine whether the effective C-ABCint dose was dependent on neocartilage maturity level. Neocartilages formed or treated per the factors above were placed into native cartilage rings, cultured for 2 weeks, and, then, integration was studied histologically and mechanically. Prior to integration, in phase II, a set of treated constructs were also assayed to provide a baseline of properties. In phase I, C-ABCint and TCL treatments synergistically enhanced interface Young's modulus by 6.2-fold (P = 0.004) and increased interface tensile strength by 3.8-fold (P = 0.02) compared with control. In phase II, the interaction of the factors C-ABCint and construct maturity was significant (P = 0.0004), indicating that the effective C-ABCint dose to improve interface Young's modulus is dependent on construct maturity. Construct mechanical properties were preserved regardless of C-ABCint dose. Applying C-ABCint to neocartilage is an effective integration strategy with translational potential, provided its dose is calibrated appropriately based on implant maturity, that also preserves implant biomechanical properties.

Clinical characteristics and prognostic risk factors of congenital pulmonary artery sling in children

Objective To analyze the clinical and imaging characteristics of pulmonary artery sling (PAS) in children and to explore its diagnosis and treatment strategies and risk factors. Method s A retrospective study was performed in 98 pediatric patients with PAS who were admitted to Guangzhou Women and Children′s Medical Center, Guangzhou Medical University, from January 2011 to October 2018.All their clinical features, imaging examination, treatment and prognosis were reviewed and analyzed. Result s (1) Among the 98 patients with PAS, 56 cases were male and 42 cases were female.The age range of onset was 0-19 months with the median age of 2 months, and the age range of diagnosis was 0-84 months with the median age of 4 months.(2) The main clinical manifestations were cough (61/98 cases, 62.24%), recurrent wheezing(47/98 cases, 47.96%), shortness of breath (43/98 cases, 43.88%), cyanosis (19/98 cases, 19.39%), and laryngeal stridor (8/98 cases, 8.16%) and so on.(3) Ninety-six patients underwent cardiac ultrasonography, and the diagnostic rate was 87.50%(84/96 cases), and 62 cases (62/96 cases, 64.58%) of them were found to be associated with other congenital cardiovascular anomalies, among which atrial septal defect was the most common (32/96 cases, 33.33%). (4) Chest CT and three-dimensional reconstruction were performed in 92 PAS children, and the diagnostic rate was 100.00%.Airway stenosis was mainly in the middle and lower sections of the main bronchus (76/92 cases, 82.61%), and bronchobridge was found in 13 cases (13/92 cases, 39.13%). Bronchoscopy was performed in 77 children with PAS, showing complete tracheal cartilage ring in 43 cases (43/77 cases, 55.84%), and tracheobronchomalacia in 13 cases (13/77 cases, 16.88%). (5) Among 67 cases who had received left pulmonary artery (LPA) reimplantation, 5 cases died after operation because of airway stenosis and weaning failure (LPA reconstruction was performed in 1 case, and both LPA reconstruction and tracheal intervention were performed in the other 4 cases), 24 cases lost to follow-up, 38 cases survived, and the respiratory symptoms were improved in 2 to 96 months of follow-up.There were 31 cases of non-surgical treatment, of which 18 cases died of respiratory failure, 7 cases lost to follow-up, and the rest 6 cases showed respiratory symptoms of different degrees in the follow-up period.(6) Multivariate regression analysis showed that conservative treatment was an independent risk factor affecting the prognosis of PAS (OR=7.45, 95%CI: 1.23-48.68). Conclusions The combination of cardiac ultrasound, chest CT and bronchoscopy is important to the diagnosis of PAS.LPA reconstruction is the main method to treat PAS, which can improve respiratory symptoms, but its fusion with tracheal intervention poses a high risk of death.Conservative treatment is an independent risk factor that affects the prognosis of PAS children. Key words: Congenital pulmonary artery sling; Cardiovascular anomalies; Child; Prognosis

Gular pouch diversity in the Chamaeleonidae.

Numerous chameleon species possess an out-pocketing of the trachea known as the gular pouch. After surveying more than 250 specimens, representing nine genera and 44 species, we describe two different morphs of the gular pouch. Species of the genera Bradypodion and Chamaeleo, as well as Trioceros goetzei, all possess a single gular pouch (morph one) formed from ventral expansion of soft tissue where the larynx and trachea meet. Furcifer oustaleti and Furcifer verrucosus possess from one to four gular pouches (morph two) formed by the expansion of soft tissue between sequential hyaline cartilage rings of the trachea. In Trioceros melleri, examples of both morphs of the gular pouch were observed. Morphometric data are presented for 100 animals representing eight species previously known to possess a gular pouch and two additional species, Bradypodion thamnobates and Bradypodion transvaalense. In the species with the absolutely and relatively largest gular pouch, Chamaeleo calyptratus, a significant difference was found between sexes in its width and volume, but not its length. In C. calyptratus, we show that an inflated gular pouch is in contact with numerous hyoid muscles and the tongue. Coupled with the knowledge that C. calyptratus generates vibrations from the throat region, we posit that the tongue (M. accelerator linguae and M. hyoglossus) and supporting hyoid muscles (i.e., Mm. sternohyoideus profundus et superficialis and Mm. mandibulohyoideus) are involved in the production of vibrations to produce biotremors that are amplified by the inflated gular pouch and used in substrate-borne communication.

The application of thyroid alar cartilage in the reconstruction of subglottic stenosis for children

Objective: To explore the application value of thyroid alar cartilage(TAC) in the laryngotracheal reconstruction of subglotticstenosis in the paediatric population. Methods: Twelve patients(7 males,5 females; range from 2.3 to 12.0 years) with subglotticstenosis who had undergone laryngotracheal reconstruction procedures at our hospital fromSeptember 2016 to July 2018 were analyzed retrospectively.The degree of stenosis was classified according to Myer-Cotton classification system:grade Ⅱ(n=4),grade Ⅲ(n=6) and grade Ⅳ(n=2). The stenosis planes were subglotticbut did not exceed the 3rd tracheal cartilage ring. Results: Of all 12 patients, 11 were decannulated and 1 failed. All patients with grade Ⅱ and Ⅲ patients were decannulated at one procedure. There were no severe complications such as tube dislogement,asphyxia and unhealed wound. Conclusions: The TAC for widening laryngotracheal lumen is relatively simple and reliable for laryngotracheal reconstruction in the pediatric population with subglottic stenosis. This would't cause any structural damage to the laryngeal cavity.

Morphology of trachea of mature chickens, grown under the conditions of radioactive contamination

The features of macro- and microscopic structure and morphometric parameters of the trachea of chickens of the Black Moscow breed of 180 days of age grown in conditionally pure and II zone of radioactive contamination are presented in the work using radiological, morphological, morphometric and statistical methods of research. It has been found that the presence of chickens in radioactively contaminated territories, feeding them with locally-sourced food, has an adverse effect on the respiratory organs, including the trachea. According to the results of radiological research, the increase of gamma background was established in the territory where the experimental part of the research was conducted. Thus, according to our observations, the specific power of the exposure dose of gamma rays for cesium-137 in the territory where the experimental animals were kept was almost in 3–3.5 times higher than this indicator for the relatively pure radioactive contamination of the territory. The specific activity of the diet for cesium-137 in chickens of 180 days of the experimental group was almost 8.5 times higher than in the control group of animals and was 13.4–16.0 Bq/kg, compared with the control (1.64–1.82 Bq/kg), indicating the cumulative capacity of this isotope. According to our research, the trachea of chickens of the experimental group has a pale pink color and is built of cartilage rings (110–120 units), which have a rounded shape. Its wall is formed by the mucous and fibrous cartilage and adventitia. The mucous membrane has a folded structure and is lined with multilayered ciliated epithelium and contains glands. Four types of cells are well differentiated into the epithelium: basal, ciliated, endocrine, and goblet. The fibrous cartilage sheath is formed by tracheal cartilages, which are interconnected by a dense fibrous connective tissue. The histoarchitectonics of the trachea of chickens reared in the second zone of radioactive contamination is similar to that of chickens in the control group. However, our morphometric studies noted that the animals of the experimental group increased the size of the terminal parts of the tracheal glands, thickened connective tissue capsules of the lymph nodes. The absolute body mass of the chickens of the experimental group, compared with the control group, tends to decrease and is respectively 2.96 ± 0.19 g, while the relative weight of the organ significantly (P ≤ 0.001) decreases to 0.284 ± 0.027%. In addition, for 180-day-old chickens that were constantly under radioactive contamination, the thickness of the mucous, fibrous, cartilage, and adventitious membranes tended to decrease compared to chickens from the conditionally clear area for radioactive contamination.

Congenital Segmental Absence of Tracheal Rings in a Kitten

Congenital anomalies of the trachea are rare in cats. This article reports segmental absence of tracheal cartilage rings in a kitten. An 8-month-old female kitten was presented with a history of weight loss and respiratory distress for 2 months. Radiographs of the thorax demonstrated a large air-filled sac suggestive of pneumomediastinum. No cartilaginous structures were evident radiographically over the caudal portion of the trachea. At necropsy examination, approximately 2cm from the carina, a 3cm segment of the trachea lacked cartilaginous rings. The clinical and morphological features of this lesion were similar to those described in human and canine cases of congenital segmental absence of tracheal rings.

A combination of tracheoplasty and tracheal stenting is an acceptable method of treating severe congenital tracheobronchial stenosis under extracorporeal membrane oxygenation

BackgroundCongenital tracheobronchial stenosis (CTBS) is a rare congenital condition characterized by complete cartilage rings covering varying lengths of the major airway. In this study, we reviewed the outcomes of patients with CTBS receiving surgical tracheoplasty in our institute. MethodsWe retrospectively analyzed the outcomes of consecutive patients with CTBS operated between 2006 and 2017 when extracorporeal membrane oxygenation (ECMO) was used perioperatively. ResultsIn total, 11 patients (median follow-up period, 4.2 years; interquartile range, 1.6–5.4) were included. Seven were symptomatic in the neonatal period, 10 had cardiorespiratory anomalies, 7 required preoperative bronchoscopic balloon dilatation, and 1 required preoperative stent placement. Slide tracheoplasty (STP) was performed in 9 patients, and 2 underwent pericardial patch tracheoplasty. Seven patients required postoperative balloon dilatation, and 6 required postoperative stent placement. Early stenting provided immediate ventilatory improvement in all patients and facilitated successful extubation in a median of 4 days after stenting in 80% of the patients. ConclusionsUnder ECMO, severe CTBS could be successfully treated through a combination of tracheoplasty and bronchoscopic management. STP provided excellent results for solitary trachea stenosis with a minimum diameter of ≥3 mm. In selected patients, postoperative tracheobronchial stent placement was crucial in minimizing the ECMO duration and facilitating extubation. Level of EvidenceIV