Tracheal Stenosis Research Articles

The role of thoracic surgery in the management of complicated acute and post-acute COVID-19 pneumonia (PASC).

COVID-19 is considered a respiratory virosis in its classic form, although it may present with heterogeneous symptoms. Thoracic complications occur in a small percentage of patients. Our objective was to evaluate existing experience with this disease and its thoracic manifestations and to determine the real-world status of care of these patients. This study is a retrospective, single-institution analysis of a group of patients hospitalized with acute and post-acute COVID-19 pneumonia at Thomayer Hospital in Prague in the period from December 2020 to March 2022 and indicated for a thoracic surgical procedure. During the peak of COVID-19 pandemic, a thoracic intervention was performed in 46 admitted patients. Thoracic drainage (due to pneumothorax in 18 cases, fluidothorax in 3 cases, CT-guided lung abscess drainage in 2 cases, and CT-guided pneumatocele drainage in 2 cases) were the most common thoracic surgical procedures. Pleurectomy/decortication surgery was done in 10 cases. Additionally, 12 lung parenchyma-sparing resections were performed, while lobectomy was required in 2 cases. Resection of postintubation tracheal stenosis due to a severe course of COVID-19 pneumonia was indicated in 2 patients. Even mild COVID-19 may cause a considerable morphological a functional alteration of the respiratory system. The most common complications of COVID-19 pneumonia that require a thoracic surgical intervention include pathologies associated with an air leak and accumulation of air (pneumothorax, pneumomediastinum and subcutaneous emphysema). The development of pulmonary necrosis, symptomatic bronchiectasis, pneumatocele, and bullous-fibrotic formations may result in pneumothorax, hemothorax or thoracic empyema in sporadic cases. An early thoracic surgical intervention to treat thoracic complications of COVID-19 pneumonia can improve the survival of COVID-19 patients.

A multicenter observational study assessing the safety, feasibility, and complications of Bonastent in central airway obstruction.

Self-expandable metallic stents (SEMS) are increasingly used in the management of both malignant and nonmalignant airway stenosis. There are multiple stents available in the market; however, the current literature on the efficacy and safety of newly available 3rd generation SEMS (Bonastent) is extremely limited and only has data from single center studies. To report the efficacy and early (<7 days) and late (⩾7 days) complications in patients with central airway obstruction (CAO) treated with Bonastent placement at two institutions. We performed a retrospective analysis of data of consecutive patients who underwent therapeutic bronchoscopy and Bonastent placement at two tertiary care university hospitals between January 2019 and November 2023. Bonastent deployment was performed in the operating room. Stents were deployed using rigid or flexible bronchoscopy under direct visualization with a flexible bronchoscope and in conjunction with fluoroscopic guidance. We then analyzed the effectiveness, short-term, and long-term complications of Bonastent placement. A total of 107 Bonastents® were placed in 96 patients. The most common etiology of CAO was malignancy, 92.7% (n = 89), followed by excessive dynamic airway collapse (EDAC) and post-intubation tracheal stenosis. Seventy-three patients (76%) had improvement in symptoms or imaging within 7 days of stent placement, including successful liberation from mechanical ventilation in a patient with CAO. Early complications occurred in seven patients (two-airway bleeding, two-mucus plugging that improved with airway clearance, two-stent migrations, and one-cough).Late complications occurred in 23 patients (1-stent migration requiring revision bronchoscopy and replacement of airway stent, 11-mucus plugging, 6-granulation tissue, 2-pneumonia, 1-cough, 1-tumor ingrowth/stent fracture, 1-airway emergency due to excessive granulation tissue obstructing the distal end of the stent and had a failed cricothyroidotomy leading to death). Overall, the early complication rate was 7.3% (7/96) and late complication rate was 23.9% (23/96). Our study is the first multicenter study that found a good safety profile with a low complication rate after tracheobronchial Bonastent placement with improvement in symptoms soon after stent placement.

Transcriptional profiling sheds light on the fibrotic aspects of idiopathic subglottic tracheal stenosis.

Idiopathic subglottic stenosis (ISGS) is a rare fibrotic disease of the upper trachea with an unknown pathomechanism. It typically affects adult Caucasian female patients, leading to severe airway constrictions caused by progressive scar formation and inflammation with clinical symptoms of dyspnoea, stridor and potential changes to the voice. Endoscopic treatment frequently leads to recurrence, whereas surgical resection and reconstruction provides excellent long-term functional outcome. This study aimed to identify so far unrecognized pathologic aspects of ISGS using single cell RNA sequencing. Our scRNAseq analysis uncovered the cellular composition of the subglottic scar tissue, including the presence of a pathologic, profibrotic fibroblast subtype and the presence of Schwann cells in a profibrotic state. In addition, a pathology-associated increase of plasma cells was identified. Using extended bioinformatics analyses, we decoded pathology-associated changes of factors of the extracellular matrix. Our data identified ongoing fibrotic processes in ISGS and provide novel insights on the contribution of fibroblasts, Schwann cells and plasma cells to the pathogenesis of ISGS. This knowledge could impact the development of novel approaches for diagnosis and therapy of ISGS.

Human tracheal transplantation: A systematic review of case reports.

Patients with long-segment airway stenosis not amenable to conventional surgery may benefit from tracheal transplantation. However, this procedure has been only anecdotally reported, and its indications, techniques, and outcomes have not been extensively reviewed. We conducted a systematic Literature search to identify all original articles reporting attempts at tracheal transplantation in humans. Of 699 articles found by the initial search, 11 were included in the systematic review, describing 14 cases of tracheal transplantation. Patients underwent transplantation for benign stenosis in nine cases, and for malignancies in five cases. In 12 cases blood supply to the trachea was provided by wrapping the graft in a vascularized recipient's tissue, while in 2 cases the trachea was directly transplanted as a vascularized composite allograft. The transplantation procedure was aborted before orthotopic transplantation in two patients. Among the remaining 12 patients, there was 1 operative mortality, while 4 patients experienced complications. Immunosuppressants drugs were administered to the majority of patients postoperatively, and only one group of authors attempted their withdrawal, in five patients. At the end of follow-up, all 11 patients surviving the operation were alive, but 2 had a recurrent tracheal stenosis requiring an airway appliance for breathing. Human tracheal transplantation is still at an embryonic phase. Studies available in the Literature report different surgical techniques, and information on long-term outcomes is still limited. Future research is needed in order to understand the clinical value of this procedure.

Non-standard long-term tracheal stenting with silicone endoprosthesis for cicatricial stenosis

Endoscopic approach with recanalization and stenting is one of the methods for cicatricial tracheal stenosis. Major complications may occur if service life of stents is not observed. However, there are currently no clear timing for stenting. In world practice, there are no indications on lifelong stenting for cicatricial tracheal stenosis. Restenosis is more common after stent removal and requires repeated stenting or another treatment. In case of prolonged stenting, silicone stent should be periodically replaced with a similar one due to destruction of silicone rubber. As a rule, this maneuver is necessary after 1-3 years. Currently, there is no information about maximum allowable duration of stent without replacement and possible complications. Condition of trachea after prolonged stenting is also unknown. We present long-term (27 years) tracheal stenting with a silicone stent. Stent fragmentation and dislocation throughout this period led to respiratory failure and emergency removal. Tracheal lumen was satisfactory immediately after procedure. However, restenosis appeared after 1.5 months and required endoscopic dilation with discussion of appropriate treatment option. However, the patient refused tracheal resection with anastomosis and underwent repeated stenting with similar stent and favorable immediate result.

Swiss Cheese Trachea: An Unwarranted, Unique Form of Post-intubation Tracheal Stenosis.

How to cite this article: Bajad P, Pahuja S, Agarwal S, Khanna A. Swiss Cheese Trachea: An Unwarranted, Unique Form of Post-intubation Tracheal Stenosis. Indian J Crit Care Med 2024;28(1):84-85.

Successful Extracorporeal Cardiopulmonary Resuscitation in a Case of Severe Tracheal Stenosis after Congenital Heart Surgery

Successful Extracorporeal Cardiopulmonary Resuscitation in a Case of Severe Tracheal Stenosis after Congenital Heart Surgery

Incidence of Tracheal Stenosis in ICU Hospitalized COVID-19 Patients: Results from a Prospective, Observational, Multicenter Study.

Background: Tracheal stenosis represents a fearsome complication that substantially impairs quality of life. The recent SARS-CoV-2 pandemic increased the number of patients requiring invasive ventilation through prolonged intubation or tracheostomy, increasing the risk of tracheal stenosis. Study design and methods: In this prospective, observational, multicenter study performed in Lombardy (Italy), we have exanimated 281 patients who underwent prolonged intubation (more than 7 days) or tracheostomy for severe COVID-19. Patients underwent CT scan and spirometry 2 months after hospital discharge and a subsequent clinical follow-up after an additional 6 months (overall 8 months of follow-up duration) to detect any tracheal lumen reduction above 1%. The last follow-up evaluation was completed on 31 August 2022. Results: In the study period, 24 patients (8.5%, CI 5.6-12.4) developed tracheal stenosis in a median time of 112 days and within a period of 200 days from intubation. Compared to patients without tracheal stenosis, tracheostomy was performed more frequently in patients that developed stenosis (75% vs 54%, p = 0.034). Tracheostomy and alcohol consumption (1 unit of alcohol per day) increased risk of developing tracheal stenosis of 2.6-fold (p = 0.047; IC 0.99-6.8) and 5.4-fold (p = 0.002; CI 1.9-16), respectively. Conclusions: In a large cohort of patients, the incidence of tracheal stenosis increased during pandemic, probably related to the increased use of prolonged intubation. Patients with histories of prolonged intubation should be monitored for at least 200 days from invasive ventilation in order to detect tracheal stenosis at early stage. Alcohol use and tracheostomy are risk factors for developing tracheal stenosis.

Down-regulation of miR-21-5p by pirfenidone to inhibit fibroblast proliferation in the treatment of acquired tracheal stenosis.

Treatment options for acquired tracheal stenosis (ATS) are limited due to a series of pathophysiological changes including inflammation and cell proliferation. Micro ribonucleic acid-21-5p (miR-21-5p) may promote the excessive proliferation of fibroblasts. However, various types of fibrosis can be prevented with pirfenidone (PFD). Currently, the effect of PFD on miR-21-5p and its biological function has not been clarified. In this study, PFD was evaluated as a potential treatment for ATS by inducing fibroblast proliferation in lipopolysaccharide (LPS)-induced fibroblasts by targeting miR-21-5p. For 48 h, 1g/ml LPS was used to generate fibroblasts in vitro, followed by the separation of cells into four groups: control, PFD, mimic, and mimic + PFD. The Cell Counting Kit-8 (CCK-8) technique was adopted to measure the proliferation of fibroblasts. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB) were used to measure the relative expressions of tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), drosophila mothers against decapentaplegic 7 (Smad7) and collagen type I alpha 1(COL1A1) messenger RNA (mRNA) and proteins, respectively. (1) At 0, 24, 48, and 72 h, fibroblast growth was assessed using the CCK-8 method. Compared with the control group, the mimic group showed the highest fibroblast viability, and the PFD group showed the lowest fibroblast viability. However, fibroblast viability increased in the mimic + PFD group but decreased in the mimic one. (2) RT-qPCR and WB showed that the mimic group exhibited a significant up-regulation in the relative expressions of TNF-α, TGF-β1, and COL1A1 mRNA and proteins but a down-regulation in the relative expression of Smad7 mRNA and protein compared with the control one. In the PFD group, the results were the opposite. Nevertheless, the relative expressions of TNF-α, TGF-β1, and COL1A1 mRNA and proteins were increased, whereas that of Smad7 mRNA was decreased in the mimic + PFD group. The change was less in the mimic group. PFD may have a preventive and curative effect on ATS by inhibiting fibroblast proliferation and the fibrotic process and possibly through down-regulating miR-21-5p and up-regulating Smad7 and its mediated fibrotic and inflammatory responses.

Experimental analysis and biaxial biomechanical behaviour of ex-vivo sheep trachea

Besides surgery, there are currently no other established methods for routine treatment of tracheal pathologies such a tracheal stenosis or tracheal and airway tumors. Even with several attempts to repair the infected trachea with artificial and natural prostheses, there is a need for the fundamental understanding of the tissue’s mechanical behaviour. The purpose of this study was to investigate the mechanical behaviour of the tracheal tissue under biaxial tensile loading. Furthermore, the study examines the material properties of the tissue through a study of the model parameters for six constitutive models. Materials and methods: The fourteen (n = 14) specimens of sheep trachea (Vleis Merino) measured to be ∼30 × 20 mm where only the effective area of ∼25 × 16 mm was subjected to engineering strain. In this study, we assume that the tracheal tissue is anisotropic and incom-pressible, therefore we apply and study the material parameters from six different constitutive material models. Results: The results show that the tracheal tissue is twice as stiff along the circumferential direction as it is along the longitudinal direction. It is also observed that the material properties are different (non-homogeneous) along the trachea. Conclusion: The findings of this study will benefit computational models for the study of tracheal diseases or injuries. Furthermore, these findings will assist in the development of regenerative medicine for different tracheal pathologies and in the bioengineering of replacement tissue in cases of damage.

DEVELOPMENT AND EXPERIMENTAL REPLICATION OF THE MODEL OF PARTIAL TRACHEAL STENOSIS IN YOUNG SEXUALLY IMMATURE WHITE RATS

This work is devoted to the development of two models of experimental replication of stenosis in the upper part of the trachea with different degrees of compression of this organ in sexually immature (one-month-old) white Wistar rats. Considering the different degrees of laryngomalacia in newborns, we developed two models: with a lower (20%) and higher (30%) degree of airway obstruction. In the first version of modeling, this was achieved by applying the ligature at the level between 1 and 2, or 2 and 3 cartilaginous semi-rings of the trachea, in the second – by applying it directly to the 2 cartilaginous semi-ring of the trachea. Both models were performed to study the state of the organism in conditions of hypoxic hypoxia in laboratory animals.&#x0D; The developed modeling methods differ from each other not only in the place of application of the compressing ligature, but also in the mechanism of compression development. In the case of applying a ligature to the intercartilaginous ligaments (20% stenosis), soft tissues are compressed and both semi-rings of the trachea are brought together. In the second variant of modeling, the pathophysiological mechanism of stenosis consists not only in the compression of the cartilaginous semi-ring of the trachea, but also in the process of invagination of the dorsal, i.e., elastic part of the trachea into the lumen of this hollow organ. As a result, a more intense variant of tracheal stenosis in experimental animals is achieved. Another important component of the developed models is the possibility at different stages of the experiment to eliminate the compressive effect of the ligature on the trachea and to study the state of various organs and tissues of animals in the early or delayed post-hypoxic periods. This leads to a significant increase in the value or efficiency of conducting this kind of experiments, taking into account the fact that hypoxic and posthypoxic periods can be studied on the same experimental animal. Both exotracheal modeling methods are fundamentally different from the endotracheal variant of experimentally reproducing stenosis. With the latter, pathological structural and functional disorders of the cells of the mucous membrane, the connective apparatus of the trachea and smooth muscle elements, the development of inflammation, and the progression of irreversible changes in the cellular and organ structures of the trachea are observed. In addition, simulation of the specified variant of stenosis requires the use of expensive equipment – a laryngoscope and some other modern technologies. Both variants of exotracheal modeling of tracheal stenosis, proposed by us, are devoid of all these shortcomings. At the same time, they enable to achieve the same degree of stenosis of this organ in animals as with the endotracheal variant.

Congenital High Airway Obstructive Syndrome (CHAOS) Survival of a Newborn with Laryngeal Atresia.

Congenital high airway obstructive syndrome (CHAOS) is a rare congenital anomaly, frequently caused by laryngeal or tracheal atresia, tracheal stenosis, and obstructing laryngeal cysts. This is a congenital malformation, often fatal, with an unknown prevalence. Laryngeal atresia is the most frequent cause. We report a case of an intrauterine diagnosis of CHAOS and ascites in a 17-week fetus delivered at 38 weeks of gestation without other associated malformations. A fetoscopic procedure was performed at 22 weeks of gestation. An attempt was made to perforate the affected area to ensure pulmonary fluid circulation and the ascites' resolution. After birth, a tracheostomy was performed. The patient was mechanically ventilated until 11 months of age, when she was discharged with no cerebral or other complications of immediate postnatal anoxia or episodes of respiratory arrest. A laryngotracheoplasty was performed at 2 years old, but decannulation was not possible due to certain complications. At 5 years old, a new surgical intervention was performed, which allowed decannulation 6 months later.

Voice Restoration after Traumatic Subglottic Tracheal Stenosis.

Tracheal stenosis post intubation is one of the most common complication for which resection and anastomosis is done.Here we present a 21 year male patient who was intubated post organophosphorous poisoning. Diagnosed with tracheal stenosis post intubation and managed with tracheal resection and anastomosis with uneventful recovery.Post intubation tracheal stenosis is one of the serious complications and requires a multidisciplinary team and high volume centre for adequate management. Considering the fact that this case report has tracheal stenosis of grade IV type with resected length of tracheal cartilage of more than 3 cm and trachea- tracheal anastomosis makes this a rare case report.

Robotic Slide Tracheoplasty for Pediatric Tracheal Stenosis in Three-Dimensional Printed and Pig Trachea Models

PurposePediatric long-segment tracheal stenosis often requires operative repair with a slide tracheoplasty performed through median sternotomy. We hypothesized that this operation can be performed through a transcervical approach with use of a single-port robotic system. DescriptionA transcervical single-port robotic slide tracheoplasty was performed in 2 models—a 3-dimensional (3D) printed pediatric tracheal stenosis model and a cadaveric pig trachea model. EvaluationSingle-port robotic slide tracheoplasty was successfully performed in both models. They were large enough that there were minimal issues with limited working space, although mediastinal structures around the trachea were not represented in the models. The advantage of the 3D printed model was the realistic anatomic tracheal stenosis; the advantage of the pig trachea model was the realistic tissue. ConclusionsTranscervical single-port robotic slide tracheoplasty was technically feasible in both our 3D printed and pig trachea models. However, given the limited working space, there are limits to the size of the patient for this technique. Further development is needed before this technique is ready for clinical use.

Radical Surgical Treatment of Idiopathic Tracheal Stenosis. A Clinical Observation

Introduction. Idiopathic cicatricial tracheal stenosis (ICTS) comprises a rare and dangerous disease of unknown etiology. Its morphological substrate consists in the formation of circular fibrotic stenosis, usually at the level of the cricoid cartilage and the first two С-shaped rings of the trachea. The first cases of the disease were described by Brandenburg only in 1972. Progression of the disease is slow, right up to severe respiratory failure and asphyxia. Treatment methods for idiopathic cicatricial tracheal stenosis include both endoscopic and open surgical techniques. However, endoscopic treatment fails to produce the desired effect. Materials and methods. The authors of the present paper performed tracheo-laryngeal resection as a radical method for treating idiopathic tracheal stenosis in a 54-year-old patient against the background of prolonged unsuccessful endoscopic treatment. The follow-up period accounted for 45 days. Examinations in the postoperative period showed complete epithelialization of the anastomosis line without inflammation. Results and discussion. Idiopathic cicatricial tracheal stenosis is considered to be a dangerous disease without significant causes of development. However, it is claimed to be a potentially curable disease, though its treatment is a difficult task. Some authors report satisfactory results of endoscopic treatment of ICTS, but most publications on this issue consider a single tracheo-laryngeal resection with anastomosis as the most optimal method of treatment, thereby correlating with the results of the present study. Conclusion. The present observation characterizes the peculiarity and possibility of radical treatment of ICTS, since the endoscopic method of treatment produces only a temporary effect. Small number of observations and lack of a coherent pathogenetic theory necessitate further research into this problem.

Application of Neck Brace as an Alternative Method of Immobilization after Circular Tracheal Resection. Case Series

Introduction. Cicatricial tracheal stenosis comprises a severe complication of traumatic or prolonged intubation of the trachea. Circular resection of the trachea serves as a radical method of surgical treatment. The distension of the anastamosis can be prevented by immobilization of the neck and head in the thoracic adduction, as a rule, with the Grillo suture technique. This method of fixation creates severe discomfort for the patient, especially when eating. Rare cases involve neurological disorders due to compression of the neurovascular bundles of the neck and spinal cord. Materials and methods. The study enrolled 6 patients diagnosed with cicatricial tracheal stenosis upon admission to the thoracic surgery unit. All patients underwent a circular tracheal resection. Immobilization of the cervical spine was performed using a cervical collar (Schantz collar type). Results. Immobilization was performed within 7–13 days, followed by a control tracheobronchoscopy. No complications related to anastomotic failure and no specific complications when using these orthoses were revealed. Discussion. The postoperative period was reported as uneventful; anastomotic healing proceeded in accordance with the physiological timing indicated by the framework of other studies. The applied orthosis provides immobilization of the cervical spine, preventing from any movement in this area, which is actually similar to the use of the Mulliken-Grillo suture, but has a number of advantages: absence of cosmetic defects, possibility of quick fixation and removal. Significantly, this provides an opportunity to assess the risk of neurochemical damage in patients during preliminary fixation of the head in the hyperflexic position at the preoperative stage. Conclusion. Having such advantages as the absence of cosmetic defects and the possibility of quick removal, this method of neck fixation can be considered as an alternative to the classical fixation method.

Treatment strategy of congenital tracheal stenosis associated with non-vascular ring cardiac malformations

Objective: To examine the treatment strategy of congenital tracheal stenosis associated with non-vascular ring cardiac malformations. Methods: This is a retrospective case series. Clinic data from 24 children with tracheal stenosis who underwent surgical treatment in the Department of Cardiac Surgery, Children's Hospital Affiliated to Shandong University from February 2017 to March 2023 were retrospectively collected. There were 16 males and 8 females, aged (M(IQR)) 6.5 (19.6) months (range: 2.2 to 66.3 months) and weighted 5.95 (4.76) kg (range: 3.2 to 20.0 kg). All patients had obvious respiratory symptoms. Eighteen patients underwent cardiac malformation correction and tracheoplasty at the same time (simultaneous group). Six patients in the staged operation group were treated with cardiac malformation correction in the first stage operation and tracheoplasty in the second stage operation due to missed diagnosis or delayed diagnosis of tracheal stenosis or no condition for tracheoplasty. Slide tracheoplasty was used to correct tracheal stenosis in both groups. The recovery of the children was followed. Wilcoxon sign rank test was used for comparison between the two groups. Results: There was no death during the perioperative period and hospitalization. In the simultaneous group, 1 case with delayed chest closure underwent bedside chest closure after 52 hours, 2 cases were intubated again after operation, and 1 case was implanted with an endotracheal stent. The duration of mechanical ventilation was 40.5 (39.6) hours (range: 19.0 to 438.8 hours). In the staged group, there was 1 case of re-intubation after operation, combined with left vocal cord paralysis and respiratory multidrug-resistant bacterial infection (Acinetobacter baumanii). One patient underwent 3 times of bronchoscopic balloon dilatation of the right middle bronchus, and heart rate returned to normal range. The duration of mechanical ventilation was 19.0 (21.4) hours (range: 17.1 to 96.7 hours). During follow-up, a patient in the simultaneous group was prone to respiratory infection and had good exercise tolerance, 1 patient in the staged group still had sputum stridor in the throat 3 months after the operation, and symptoms improved significantly 6 months after the operation. The other children didn't have obvious respiratory symptoms. Conclusions: The diagnosis of tracheal stenosis may be delayed or missed when tracheal stenosis is complicated by non-vascular ring cardiac malformations. One-stage correction of tracheal stenosis and cardiac malformation can achieve a good outcome.

Successful Dilation and Stenting of Severe Tracheal Stenosis Following Brief Intubation

Tracheal stenosis following brief intubation is a relatively rare but serious problem. However, some degree of airway injury is common following intubation, regardless of the duration. We herein report a rare case of a female patient in her late sixties, who developed severe tracheal stenosis following just a weeklong intubation. The tracheal stenosis was successfully treated via dilation and stenting using a self-expanding metal stent.

Functional and nonfunctional parathyroid carcinoma: two case reports and literature review

Parathyroid carcinoma (PC) is a rare malignant endocrine tumor. It can be divided into functional and non-functional types according to the tumor’s ability to secrete parathyroid hormone. Herein, we present a case each of functional and nonfunctional PC. Case 1: Functional PC. The main clinical symptoms were high parathyroid hormone and hypercalcemia with bone injury and other complications. The mass was large, capsulated, and showed vascular invasion. The tumor was surgically removed, along with a part of the tracheal wall and recurrent laryngeal nerve that were invaded by the tumor. The ipsilateral and isthmus thyroid lobe and central lymph nodes were also removed. Medicines were given to lower blood calcium. The patient died 18 months after surgery because of severe pulmonary infection and tracheal stenosis. Case 2: Non-functional PC. The patient showed no obvious clinical symptoms, but physical examination revealed a thyroid nodule. Despite the small diameter, the mass still invaded the surrounding thyroid lobe, fat, and muscle tissue. Surgery was performed to remove the tumor and ipsilateral thyroid lobe and central lymph nodes. The patient survived without recurrence or metastasis. Thus, we believe that the prognosis of PC negatively correlates with the scope of surgery. Early surgery can improve patient prognosis, and physical examination is conducive to early detection of PC. Herein, we provide a description of the diagnostic workup and the treatment approach and review relevant studies. We summarize the clinicopathological characteristics of PC cases to provide evidence for early diagnosis and therapy, to improve patient prognosis.

Successful One-Lung Ventilation Using Bronchial Blocker in Extremely Severe Tracheal Stenosis

Successful One-Lung Ventilation Using Bronchial Blocker in Extremely Severe Tracheal Stenosis