Entire Trachea Research Articles

Regional variations and sex-related differences of stiffness in human tracheal ligaments.

There have been numerous studies focused on the stiffness of tracheal cartilage. However, no research has been conducted specifically on the annular ligament, nor have any regional differences in the annular ligament been identified. The purpose of this study was to investigate the stiffness of the ligaments present between the thyroid, cricoid and tracheal cartilages. The ligaments were identified in the cervical region of living subjects with ultrasonography. The stiffness of the ligaments was measured from the body surface using a digital palpation device (MyotonPRO). Since it is impossible to measure the entire trachea in a living subject, an additional measurement was performed on human cadavers. Both in vivo and cadaveric investigations found that the stiffness of annular ligaments decreased gradually from the superior to inferior parts. There was no difference in the stiffness between males and females in the superior part of the trachea. However, the stiffness of the middle and inferior parts was predominantly higher in females than in males. Furthermore, males showed significant differences in stiffness between the superior and middle parts, while females showed no significant differences. These results reveal that there are regional and sex-related differences in the stiffness of human tracheal ligaments.

Mediastinitis after a cryopreserved allograft tracheal transplant treated by transposition of the major omentum.

A 56-year-old female presented with an extended adenoid cystic carcinoma of the entire trachea. She underwent a 12-cm fully-circumferential tracheal replacement by a cryopreserved aortic allograft(CAA) stented by a silicon prosthesis to prevent airway collapse. A muscle flap was used to provide neovascularization and prevent fistulization to mediastinal structures. Post-surgery mediastinitis was detected three weeks after surgery and reoperation was performed. A partial allograft necrosis with stent exposure was found. Major omentum transposition allowed neo-trachea coverage, preventing air-leak, providing antibiotics delivery and mediastinal infection treatment. Six months after surgery the patient is alive. Follow-up bronchoscopy showed a satisfactory allograft revascularization.

Acute tracheal trauma and chronic tracheal collapse in an asthmatic mature pony

SummaryA 17‐year‐old cross‐bred pony gelding was presented for acute onset of respiratory distress and an inspiratory honking noise. He had been previously diagnosed with moderate mastocytic equine asthma and chronic tracheal collapse on endoscopy (grade 3/4). At admission, predominantly inspiratory dyspnoea with open mouth breathing, hypoxaemia and hypercapnia were present. Cervical and thoracic radiographs showed severe tracheal collapse from the mid‐cervical region to the thoracic inlet and a moderate generalised bronchial pattern. Due to the poor prognosis, euthanasia was elected. On post‐mortem examination, some granulomatous nodules compatible with tracheobronchopathia osteochondroplastica were present in the tracheal lumen, and the entire trachea was laterally flattened. This uncommon laterolateral collapse was more severe at the thoracic inlet and in the mid‐cervical area, where a peritracheal haematoma was detected. A blunt trauma that exacerbated the tracheal collapse was suspected. Tracheal histology revealed degenerative changes. Degeneration of tracheal cartilage and connective tissue can be a predisposing factor to chronic collapse and recurrent episodes of inspiratory and expiratory distress. It is unknown whether chronic tracheal collapse is an independent condition or a consequence of an underlying lung disease.

Therapeutic bronchoscopy followed by sequential radiochemotherapy in the management of life-threatening tracheal adenoid cystic carcinoma: a case report

BackgroundAdenoid cystic carcinoma of the lung is a distinctive salivary-gland-type malignant epithelial neoplasm that rarely presents as a primary tumor of the respiratory tract. Complete surgical resection remains the treatment of choice for adenoid cystic carcinoma. We present a case of large ACC tumors that caused severe central airway obstruction and were effectively treated with therapeutic bronchoscopy followed by radiotherapy and chemotherapy.Case presentationA 31-year-old Malay Indonesian female patient who was a nonsmoker and had no family history of cancer was admitted to the emergency ward because of worsening breathlessness accompanied by stridor since 1 week prior. Chest computed tomography revealed segmental atelectasis of the left lung; a mass on the left main bronchus, with infiltrates in segments 1, 2, and 3 of the left lung; and consolidation in the left inferior lobe, with narrowing of the main left bronchus. Lobulated masses obstructing almost the entire distal trachea up to the carina and the entire left main bronchus were found on bronchoscopy. Owing to the large tumors causing severe central airway obstruction, the medical team decided to perform central airway mass removal through rigid bronchoscopy. A neodymium-doped yttrium-aluminum-garnet laser was used first to facilitate mass shrinkage. After the laser treatment, mechanical mass removal using a rigid scope was performed. The tracheal and carinal lumens were opened to > 50% of their diameter, with the left main bronchus lumen opened only slightly. After the treatment, the patient was stable, and no stridor was found. Adjuvant intensity-modulated radiotherapy and chemotherapy were performed after the therapeutic bronchoscopy. At the end of the entire treatment, reevaluation by thoracic computed tomography scan and bronchoscopy revealed no remaining mass.ConclusionsIn cases of nonresectable large adenoid cystic carcinoma tumors with life-threatening central airway obstruction, therapeutic bronchoscopy followed by sequential radiochemotherapy might achieve a complete response outcome.

Left rotation and dorsoventral collapse of the trachea on an adult Dartmoor cross‐gelding: Imaging diagnosis

A 9-year-old Dartmoor cross-gelding was referred for investigation and treatment of exercise intolerance, cough and abnormal respiratory noise. Endoscopic examination revealed the presence of left 90-degree rotation and dorsoventral collapse of the entire cervical trachea. Although the tracheal collapse was not obvious on laterolateral radiographs, these showed the abnormal presence of tracheal cartilages along with the dorsal and ventral limits of the trachea. Oblique radiographs showed partial tracheal collapse in the caudal aspect of the neck. Ultrasound examination revealed the presence of tracheal cartilages on the right side of the neck, dorsal tracheal ligament along with the left side of the neck and the junction between tracheal cartilage and dorsal tracheal ligament coursing over the ventral aspect of the neck. This report highlights the value of detailed examination of standard and non-standard radiographic and ultrasound imaging of the trachea to achieve correct diagnosis of tracheal collapse when associated with tracheal rotation.

Control of hormone-driven organ disassembly by ECM remodeling and Yorkie-dependent apoptosis

Epithelia grow and shape into functional structures during organogenesis. Although most of the focus on organogenesis has been drawn to the building of biological structures, the disassembly of pre-existing structures is also an important event to reach a functional adult organ. Examples of disassembly processes include the regression of the Müllerian or Wolffian ducts during gonad development and mammary gland involution during the post-lactational period in adult females. To date, it is unclear how organ disassembly is controlled at the cellular level. Here, we follow the Drosophila larval trachea through metamorphosis and show that its disassembly is a hormone-driven and precisely orchestrated process. It occurs in two phases: first, remodeling of the apical extracellular matrix (aECM), mediated by matrix metalloproteases and independent of the actomyosin cytoskeleton, results in a progressive shortening of the entire trachea and a nuclear-to-cytoplasmic relocalization of the Hippo effector Yorkie (Yki). Second, a decreased transcription of the Yki target, Diap1, in the posterior metameres and the activation of caspases result in the apoptotic loss of the posterior half of the trachea while the anterior half escapes cell death. Thus, our work unravels a mechanism by which hormone-driven ECM remodeling controls sequential tissue shortening and apoptotic cell removal through the transcriptional activity of Yki, leading to organ disassembly during animal development.

Construction of a detachable artificial trachea model for three age groups for use in an endotracheal suctioning training environment simulator.

Tracheal suctioning is an important procedure to maintain airway patency by removing secretions. Today, suctioning operators include not only medical staff, but also family caregivers. The use of a simulation system has been noted to be the most effective way to learn the tracheal suctioning technique for operators. While the size of the trachea varies across different age groups, the artificial trachea model in the simulation system has only one fixed model. Thus, this study aimed to construct multiple removable trachea models according to different age groups. We enrolled 20 patients who had previously received proton beam therapy in our institution and acquired the treatment planning computed tomography (CT) image data. To construct the artificial trachea model for three age groups (children, adolescents and young adults, and adults), we analyzed the three-dimensional coordinates of the entire trachea, tracheal carina, and the end of the main bronchus. We also analyzed the diameter of the trachea and main bronchus. Finally, we evaluated the accuracy of the model by analyzing the difference between the constructed model and actual measurements. The trachea model was 8 cm long for children and 12 cm for adolescents and young adults, and for adults. The angle between the trachea and bed was about 20 degrees, regardless of age. The mean model accuracy was less than 0.4 cm. We constructed detachable artificial trachea models for three age groups for implementation in the endotracheal suctioning training environment simulator (ESTE-SIM) based on the treatment planning CT image. Our constructed artificial trachea models will be able to provide a simulation environment for various age groups in the ESTE-SIM.

Clinical course of tracheobronchopathia osteochondroplastica.

BackgroundTracheobronchopathia osteochondroplastica (TPO) is characterized by the presence of diffuse cartilaginous or bony submucosal nodules that lead to airway lumen narrowing. So far, there was no study in South Korea analysing a large number of TPO patients. We aimed to elucidate its treatment strategy and clinical course by analysing the characteristics of TPO patients.MethodsIn this retrospective study, we reviewed the clinical data of 40 patients diagnosed with TPO by bronchoscopy between October 1997 and April 2019 at a single referral hospital.ResultsOf the 40 patients, 26 (65.0%) were male and the median age was 63.0 years. The most common symptom was cough (n=12, 30%). Pulmonary function test (PFT) revealed an obstructive pattern in 10 (25.7%) patients. Chest computed tomography (CT) scan showed 23 (62.6%) patients with diffuse narrowing and calcified nodules. In bronchoscopy, the entire trachea was found to be involved in 30 (75.0%) patients and airway narrowing was identified in 6 (15.0%) patients. Endobronchial biopsies were obtained from 15 patients and the most common findings included typical cartilaginous and bony tissues (n=14, 93.3%). Since most patients were asymptomatic or had mild symptoms, they did not undergo any specific treatment. Of the 19 symptomatic patients, 2 (5.0%) patients received laser therapy for treating tracheal stenosis.ConclusionsTPO is a slowly progressing disease and is well managed with conservative therapies. Although TPO shows a distinctive pattern by bronchoscopy, it follows a benign clinical course.

Use of computational fluid dynamics to compare upper airway pressures and airflow resistance in brachycephalic, mesocephalic, and dolichocephalic dogs

Brachycephalic dog breeds are prone to breathing difficulties because of their upper airway anatomy. Several surgical techniques exist to correct anatomical pathologies and common surgical approaches aim to correct functional abnormalities in the nares and/or the soft palate. However, further research is needed to improve clinical outcomes. This study evaluated air pressure and airflow resistance in the upper airways and trachea in nine sedated, sternally recumbent dogs of different skull types (dolichocephalic, n=3; mesocephalic, n=3; brachycephalic, n=3). CT images were acquired from the nostrils to the caudal border of the lungs and geometrical reconstruction of the upper airway and trachea was performed. Analysis of computational fluid dynamics was performed using inspiratory flow adapted to bodyweight for each dog. Flow (L/min) and pressure (cmH2O) were computed for the entire upper airway and trachea. Resistance (cmH2O/L/min) was calculated using pressure differences between the nose, larynx, and trachea. In this pilot study, statistical comparisons were not performed.Pressure maps, airflow, and resistance were similar in dolichocephalic and mesocephalic breeds. Median pressure difference (3.76cmH2O) and resistance (0.154cmH2O/L/min) between the nose and larynx were numerically higher in brachycephalic dogs than in other breeds (0.45cmH2O and 0.016cmH2O/L/min, respectively). Median pressure difference (0.205cmH2O) and resistance (0.009cmH2O/L/min) between the larynx and trachea was numerically similar in all dogs, except for the English bulldog. The methodology used in this preliminary study to quantify airflow characteristics such as pressure and resistance could improve the understanding of brachycephalic obstruction airway syndrome.

Use of laryngeal mask after repeated endotracheal intubation failure in a patient with tracheobronchopathia osteochondroplastica: case report

We report a case of difficult endotracheal intubation in a patient with tracheobronchopathia osteochondroplastica. A 65-year-old man was scheduled to undergo ulnar nerve decompression and ganglion excisional biopsy under general anesthesia. During induction of general anesthesia, an endotracheal tube could not be advanced through the vocal cords due to resistance. A large number of nodules were identified below the vocal cords using a Glidescope® video-laryngoscopy, and fiberoptic bronchoscopy revealed irregular nodules on the surface of the entire trachea and the main bronchus below the vocal cords. Use of a small endotracheal tube was attempted and failed. a laryngeal mask airway (LMA Supreme ™) rather than further intubation was successfully used to maintain the airway.

Morphometric characterisation of human tracheas: focus on cartilaginous ring variation

PurposeDetails regarding tracheal anatomy are currently lacking, with existing literature focussing mainly on the cricoid-tracheal region or the carina. External gross anatomy and internal morphology throughout the entire trachea is important for normal physiological functioning and various clinical applications such as designs for tracheal implants or endotracheal devices.ObjectiveTo determine quantitative and qualitative characteristics of gross tracheal and individual tracheal ring anatomy.Method10 tracheas were harvested from formaldehyde-fixed cadavers. Tracheal length, height and inter-ring distance were measured from complete tracheas. Individual rings were excised and the following measurements were taken at three points on the ring: thickness, width, and antero-posterior (A-P) length.ResultsThe average tracheal length was 10.38 ± 0.85 cm with a mean of 19 ± 3 rings per trachea. The average width and A-P diameter of tracheal lumens were 17.31 ± 2.57 and 17.27 ± 2.56 mm, with a width-AP ratio of 1.00 (‘C’ shaped ring). The A-P diameter shows a trend of narrowing slightly from the upper 1/3 to the lower 1/3 of the trachea. While majority of tracheal rings consisted of the expected ‘C’ shape, more than 41% of the 147 counted rings consisted of abnormally shaped rings which were further analysed.ConclusionThis study provides further details regarding tracheal anatomy which will be useful for implant design. Of interest for anatomists, is the marked variability in tracheal ring morphology which could be further characterised in larger studies.

The Association of Mounier-Kuhn Syndrome and Pulmonary Aspergillomas: A Case Report

A 60-year-old woman was admitted to our hospital with dyspnea, a cough and hemoptysis. She had a history of long-term treatment of asthma and recurrent lower respiratory tract infections. She had been hospitalized twice in the previous 3 years to treat non-massive hemoptysis caused by cystic bronchiectasis, but without pulmonary aspergillomas. Chest computed tomography (CT) revealed tracheobronchomegaly involving the entire trachea and main bronchi. The transverse and sagittal diameters of the trachea were 36.5 and 29.9 mm, respectively. Diverticula were evident in the posterolateral proximal tracheal wall and cystic bronchiectasis with pulmonary aspergillomas was detected in both lower lung lobes (Figure 1). Fiberoptic bronchoscopy revealed a dilated trachea, diverticula in the posterolateral region of the proximal tracheal wall, and enlargement of both main bronchi. The cartilage rings of the trachea and main bronchi were notably prominent. Mucosal atrophy of both the trachea and bronchi was also evident (Figure 2). Pathological examination of bronchial lavage specimens revealed septate hyphae typical of Aspergillus spp.; the septae branched at a 45° angle. In the absence of any secondary cause of the tracheobronchial dilation, we diagnosed Mounier–Kuhn syndrome (MKS) with tracheal diverticula and pulmonary aspergillomas. Oral itraconazole and tranexamic acid were started. Although we advised surgery to counter the probably life-threatening massive hemoptysis, the patient refused. She recovered rapidly from the hemoptysis, which did not recur. The patient continues on oral itraconazole and has been followed without complications for two months.

Severe tracheal and bronchial collapse in adults with type II mucopolysaccharidosis.

BackgroundMucopolysaccharidosis type II (MPSII) patients frequently suffer from dyspnoea caused by restrictive airway disease due to skeletal abnormalities as well as glycosaminoglycans (GAG) accumulation at different levels of the airway, including the trachea. In this study we describe the extent of the tracheal and bronchial narrowing, the changes in airway diameter during respiration and the effects of these obstructions on respiratory function in adult MPSII patients.MethodsFive adult MPSII patients (mean age 40 years) were included. Pulmonary function tests and in- and expiratory chest CT scans were obtained. Cross-sectional areas of trachea and main bronchi were measured at end-inspiration and -expiration and percentage collapse was calculated.ResultsThere was diffuse narrowing of the entire intra-thoracic trachea and main bronchi and severe expiratory collapse of the trachea in all patients. At 1 cm above the aortic arch the median % collapse of the trachea was 68 (range 60 to 77 %), at the level of the aortic arch 64 (range 21–93 %), for the main bronchi this was 58 (range 26–66 %) on the left and 44 (range 9–76 %) on the right side. The pulmonary function tests showed that this airway collapse results in obstructive airway disease in all patients, which was severe (forced expiratory volume <50 % of predicted) in four out of five patients.ConclusionIn adult MPS II patients, central airways diameters are strikingly reduced and upon expiration there is extensive collapse of the trachea and main bronchi. This central airways obstruction explains the severe respiratory symptoms in MPSII patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s13023-016-0425-z) contains supplementary material, which is available to authorized users.

Vocal Hoarseness and a Subglottic Mass

We report a patient with tracheopathia osteoplastica (TPO), a rare or perhaps underrecognized disorder, detected in approximately 1 in every 2000 to 5000 patients who undergo bronchoscopy. TPO is marked by proliferation of bony and cartilaginous spurs leading to airway stenosis. Multiple submucosal cartilaginous and osseous nodules can develop in the respiratory tract and may involve the entire trachea and mainstem bronchi. Symptoms may range from a completely silent condition to life-threatening respiratory failure and diagnosis is made based on radiological and bronchoscopic findings. Although the etiology has not been established, TPO can be familial and is sometimes associated with chronic inflammation, such as seen with rheumatic diseases. This case highlights the need for understanding TPO so that it can be differentiated from potentially serious conditions such as necrotizing granulomatous diseases, invasive infections, and cancer.

Use of nitinol self-expandable stents in 26 dogs with tracheal collapse

A study was designed to describe a novel approach to the treatment of tracheal collapse (TC) in dogs using self-expandable nitinol stents. Medical records were reviewed retrospectively for 26 client owned dogs in which nitinol stents were deployed. The entire length of trachea was supported independently of the extent of TC. Two overlapping stents were used instead of one in cases where one stent was not spanning the entire trachea adequately. The diameter of the cranial radiolucent portion of trachea, just behind the cricoid cartilage, was measured as a specific landmark to select the appropriate size of the stent. Two self-expandable nitinol stents were inserted in 9 of 26 dogs; the trachea in the rest of the cases was supported with only one stent. A follow up tracheoscopy was performed in 10 of 26 cases with recurrent clinical signs. Secondary tracheal stenosis in these cases was caused by stent fracture, granuloma or excessive stent shortening. Additional stents were placed successfully to expand the stenotic lumen. A support of the entire trachea may decrease risk of nitinol fracture at the end of the implant. Long term clinical improvement (25 of 26 dogs, 96 %) is comparable with the results of other studies.

RETRACTED: Airway Transplantation

No definitive solution has been discovered for replacing long segments or the entire trachea in humans. Most of this challenge stems from the specific function and mechanics that are almost impossible to replicate except in the setting of an allotransplantation, which requires lifelong immunosuppressive medication. Recently, tissue engineering provided significant evidence concerning the next promising therapeutic alternative for tracheal replacement. Underlying mechanism and pathways of cell-surface interactions, cell migration, and differentiation are essential to understand the complexity of tracheal tissue regeneration. Tracheal replacement remains challenging but initial steps toward an ideal therapeutic concept have been made.

A preliminary study of computer assisted evaluation of congenital tracheal stenosis: A new tool for surgical decision-making

ObjectiveCongenital tracheal stenosis is a rare but severe condition with tracheal narrowing. There is no absolute correlation between luminal diameter and prognosis, and therapeutic decisions are difficult for intermediate cases. The aim of this study was to develop a dynamic model of the ventilatory consequences of congenital tracheal stenosis using computational fluid dynamics. MethodsIn 8 children with congenital tracheal stenosis and 1 healthy child, 3-dimensional geometries of the trachea were constructed with computed tomography images and specialized software (ITK-SNAP). Airflow simulations were performed for each geometry using 2 physiologic inhalation flow rates under steady and laminar flow conditions. Flow velocity, static and total airway pressure, and pressure drop across the entire trachea were determined. ResultsIn the patients with congenital tracheal stenosis, the pressure drop from the tracheal inlet to outlet, at flow rate 3L/min, ranged from 14 to 430Pa; the pressure drop at flow rate 7.3L/min ranged from 60 to 1825Pa. The pressure drop enabled a classification based on the severity of stenosis. The classification based on pressure drop was retrospectively consistent with the classification based on clinical data from the patients. ConclusionsSimulations with computational fluid dynamics may provide an objective method to evaluate the severity of the symptoms in patients with congenital tracheal stenosis and may help guide treatment.

Severe tracheobronchial stenosis and cervical vertebral subluxation in X-linked recessive chondrodysplasia punctata

Radiologic manifestations of X-linked chondrodysplasia punctata (CDPX1) typically include chondrodysplasia, epiphyseal stippling, punctate calcification of cartilage, distal phalangeal hypoplasia, and nasal/midface hypoplasia. We present an infant with CDPX1 demonstrating calcification and stenosis of the entire trachea and mainstem bronchi, as well as possible anterior C1 subluxation due to progression of congenital vertebral dysplasia.

Congenital tracheal stenosis and an anomalous origin of the right upper lobe bronchus

In October, 2006, a 29-year-old woman visited our hospital because of severe dyspnoea. She had a history of recurrent respiratory infections. On admission, mild wheezing was noted at rest, and on exercise she developed a noticeable stridor. Serum C-reactive protein was slightly increased. Initially, she was treated for asthma with oxygen and nebulised salbutamol and dexamethasone. A highresolution CT scan of the chest the following day showed striking narrowing of the entire trachea with a 7 mm anteroposterior diameter. A three-dimensional image reconstructed from the CT scan showed generalised hypoplasia of the trachea and an anomalous origin of the right upper lobe bronchus with a narrow opening (fi gure). Final diagnosis was congenital tracheal stenosis with viral respiratory infection. She was successfully treated and was discharged in November, 2006. Although very rare, congenital tracheal stenosis should be considered as a diff erential diagnosis of intractable adult asthma. Lancet 2008; 371: 1526

A case of retropharyngeal Lipoma

Lipomas are one of the most common benign mesenchymal tumors in the body. Usually asymptomatic, they rarely warrant treatment unless they attain enormous size causing cosmetic deformity or pressure effects. Head and neck region is an uncommon site, retropharyngeal space being one of the rarest. Lipomas in this region can produce pressure symptoms demanding surgical excision.This is a case report of retropharyngeal lipoma, extending from skull base to the clavicle. Though tumor was present for 20 yrs it exhibited rapid growth over a period of 2-3 yrs causing respiratory obstruction, dysphagia & dysphonia. Clinically the entire laryngopharynx, trachea and carotid sheath were pushed anteriorly. On imaging, it showed classical features of a lipomatous mass. Patient underwent complete excision which presented a surgical challenge to surgeon and the anaesthetist from intubation to extubation.