Tracheal Bifurcation Research Articles

Nonintubated Robotic-assisted Thoracic Surgery for Tracheal/Airway Resection and Reconstruction: Technique Description and Preliminary Results.

Objective:We aim to report a novel surgical technique that RATS combined with nonintubated spontaneous ventilation to perform tracheal/airway surgery.Summary of Background Data:Our team has demonstrated video-assisted transthoracic surgery can be used for thoracic tracheal diseases with satisfactory outcomes. Our team has also demonstrated that tracheal/airway resection and reconstruction under spontaneous ventilation can improve the anastomosis and operating time. Recently, RATS emerged as an available alternative minimally invasive approach for lung cancer, with lower perioperative mortality and conversion rate to open.Methods:Five patients fulfilling the criteria for nonintubated approach underwent RATS tracheal/airway surgery. Patient 1 has a tumor in the thoracic trachea; patient 2 had involving secondary carina; patient 3 had involving trachea carina, and patient 4 had involving left main bronchus. Patient 5 had involving mid-tracheal.Results:All patients had an uneventful procedure. The total operative time ranged from 5 hours 5 minutes to 9 hours 55 minutes. The postoperative hospital stays ranged from 4 days to 14 days. Fiber-optic bronchoscopy performed 1 month after the procedure showed good anastomotic healing with no stricture.Conclusion:This is the first report on RATS use in tracheal/airway surgery, in combination with nonintubation spontaneous ventilation. In selected patients, this novel combined approach is feasible and safe. A patient can potentially benefit from the combined advantages of both techniques. More cases and longer-term data are required to establish its role in tracheal/airway surgery.

Customized self-expanding bare metal Y stents in the treatment of malignant carinal stenosis: a retrospective analysis.

Self-expanding Y metal stent insertion is a safe and effective palliative method for malignant lesions involving the lower trachea, tracheal carina, and the main-stem bronchi. However, the length and degree of airway stenosis in different patients tend to vary, which leads to a call for a customized Y stent that could achieve a better treatment effect. This retrospective analysis included patients who received customized self-expanding bare metallic Y stents for malignant carinal stenosis at Beijing Tiantan Hospital, Capital Medical University between January 2007 and June 2020. CT scans and initial bronchoscopy were performed to provide reliable data for stent selection and size customization. Data on technical success, clinical success, and follow-up were analyzed. A total of 36 patients (26 males and 10 females; median age, 61 years; age range, 30-83 years) were enrolled. Technical success was 97.2% (35/36), while clinical success was 97.2% (35/36). There was no procedure-related mortality. Out of 35 patients, 4 (11.4%) had stent-associated complications that did not affect the procedure of stent insertion. Re-stenosis of the stent due to tumor progression was the main mid- and long-term stent-related complication (65% and 57.1%, respectively), followed by stent fractures (5% and 14.3%, respectively). The current study described the design and insertion of customized self-expanding bare metal Y-stents and demonstrated the feasibility of their use for maintaining tracheal and main-stem bronchus patency in malignant carinal stenosis. This approach could be used as a bridging method before commencing adjuvant therapy and final palliative therapy for the relief of symptoms.

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.

Histological study of the thin membranous dense connective tissue around the middle and lower thoracic esophagus, caudal to the bifurcation of the trachea.

We previously reported on the thin membranous dense connective tissue around the esophagus in the upper mediastinum. This time, we histologically investigated the existence of similar structures in the middle and lower mediastinum, caudal to the bifurcation of the trachea. Semi-sequential transverse sections of the mediastinum were obtained from two cadavers. Hematoxylin and eosin staining and Elastica van Gieson staining were performed. In the middle mediastinum, the "visceral sheath" could not be observed completely around the esophagus. In the lower mediastinum, the thin membranous dense connective tissue was observed beneath the pericardium on the ventral side of the esophagus. On the dorsal side of the esophagus, two thin membranous dense connective tissues were similarly observed in two cadavers. One existed between the dorsal side of the esophagus and the three vessels (i.e., the descending aorta, the azygos vein and the thoracic duct) and was integrated with the thin membranous dense connective tissue of the ventral side of the esophagus at the bilateral side of the esophagus. This integrated dense connective tissue reached the left subpleural region and the adventitia of the aorta on the left side and the peripleural and pulmonary hilum on the right side. The other thin membranous dense connective tissue, which represents the "vascular sheath", was observed between the descending aorta and the thoracic duct. These two thin membranous dense connective tissues, which are considered to represent the visceral sheath and vascular sheath, are thought to be available as optimal dissecting layers for radical esophagectomy.

Spatial and temporal distribution and predictive value of chest CT scoring in patients with COVID-19

Objective: To explore a modified CT scoring system, its feasibility for disease severity evaluation and its predictive value in coronavirus disease 2019 (COVID-19) patients. Methods: This study was a multi-center retrospective cohort study. Patients confirmed with COVID-19 were recruited in three medical centers located in Beijing, Wuhan and Nanchang from January 27, 2020 to March 8, 2020. Demographics, clinical data, and CT images were collected. CT were analyzed by two emergency physicians of more than ten years' work experience independently through a modified scoring system. Final score was determined by average score from the two reviewers if consensus was not reached. The lung was divided into 6 zones (upper, middle, and lower on both sides) by the level of trachea carina and the level of lower pulmonary veins. The target lesion types included ground-glass opacity (GGO), consolidation, overall lung involvement, and crazy-paving pattern. Bronchiectasis, cavity, pleural effusion, etc., were not included in CT reading and analysis because of low incidence. The reviewers evaluated the extent of the targeted patterns (GGO, consolidation) and overall affected lung parenchyma for each zone, using Likert scale, ranging from 0-4 (0=absent; 1=1%-25%; 2=26%-50%; 3=51%-75%; 4=76%-100%). Thus, GGO score, consolidation score, and overall lung involvement score were sum of 6 zones ranging from 0-24. For crazy-paving pattern, it was only coded as absent or present (0 or 1) for each zone and therefore ranging from 0-6. Results: A total of 197 patients from 3 medical centers and 522 CT scans entered final analysis. The median age of the patients was 64 years, and 54.8% were male. There were 76(38.8%) patients had hypertension and 30(15.3%) patients had diabetes mellitus. There were 75 of the patients classified as moderate cases, as well as 95 severe cases and 27 critical cases. As initial symptom, dry cough occurred in 170 patients, 134 patients had fever, and 125 patients had dyspnea. Reparatory rate, oxygen saturation, lymphocyte count and CURB 65 score on admission day varied among patients with different disease severity scale. There were 50 of the patients suffered from deterioration during hospital stay. The median time consumed for each CT by clinicians was 86.5 seconds. Cronbach's alpha for GGO, consolidation, crazy-paving pattern, and overall lung involvement between two clinicians were 0.809, 0.712, 0.678, and 0.906, respectively, showing good or excellent inter-rater correlation. There were 193 (98.0%) patients had GGO, 147 (74.6%) had consolidation, and 126(64.0%) had crazy-paving pattern throughout clinical course. Bilateral lung involvement was observed in 183(92.9%) patients. Median time of interval for CT scan in our study was 7 days so that the whole clinical course was divided into stages by week for further analysis. From the second week on, the CT scores of various types of lesions in severe or critically patients were higher than those of moderate cases. After the fifth week, the course of disease entered the recovery period. The CT score of the upper lung zones was lower than that of other zones in moderate and severe cases. Similar distribution was not observed in critical patients. For moderate cases, the ground glass opacity score at the second week had predictive value for the escalation of the severity classification during hospitalization. The area under the receiver operating characteristic curve was 0.849, the best cut-off value was 5 points, with sensitivity of 84.2% and specificity of 75.0%. Conclusions: It is feasible for clinicians to use the modified semi-quantitative CT scoring system to evaluate patients with COVID-19. Severe/critical patients had higher scores for ground glass opacity, consolidation, crazy-paving pattern, and overall lung involvement than moderate cases. The ground glass opacity score in the second week had an optimal predictive value for escalation of disease severity during hospitalization in moderate patients on admission. The frequency of CT scan should be reduced after entering the recovery stage.

КОМПРЕССИЯ ЛЕВОГО ГЛАВНОГО БРОНХА ПРИ ТУБЕРКУЛЕЗНОМ ПОРАЖЕНИИ МЕДИАСТИНАЛЬНЫХ ЛИМФАТИЧЕСКИХ УЗЛОВ У РЕБЕНКА ТРЕХ МЕСЯЦЕВ

The article presents a case of successful surgical treatment of a 3-month-old child with a rare pathology – tuberculosis lesion of the intrathoracic lymph nodes causing compression of the left main bronchus. The child was admitted with signs of respiratory failure. An X-ray examination revealed signs of emphysema of the left lung. According to the data of contrast CT, a volumetric hypodensive formation was detected, which slightly accumulated contrast, with a capsule up to 0,3 cm thick, located in the area of the tracheal bifurcation, causing compression of the left main bronchus, esophagus, pulmonary bifurcation. During tracheobronchoscopy, a narrowing of the main bronchus to 1 mm was found immediately after bifurcation of the trachea. During the operation, a formation with a diameter of up to 2 cm was removed. According to the results of a morphological study, the formation is regarded as tuberculous granulomatous inflammation of the lymph node. The rarity of the pathology causes difficulties in diagnosis and treatment.

Echocardiographic Evaluation of the Thoracic Aorta: Tips and Pitfalls.

By convention, the ascending aorta is measured by echo from leading edge to leading edge. “Leading edge” connotes the edge of the aortic wall that is closest to the probe (at the top of the inverted “V” of the ultrasound image). By transthoracic echo (TTE), the leading edges are the outer anterior wall and inner posterior wall. By transesophageal echo (TEE), the leading edges are the outer posterior wall and inner anterior wall. Aortic measurements should be taken (by convention) in diastole (when the aorta is moving least). Simple TTE is 70 to 85% sensitive in diagnosing ascending aortic dissection. TEE sensitivity approaches 100%, though the tracheal carina imposes a blind spot on TEE, impeding visualization of distal ascending aorta and proximal aortic arch. While computed tomography angiography may be superior for defining full anatomic extent of aortic dissection, echocardiography is superior in assessing functional consequences such as mechanism and severity of aortic regurgitation, evidence of myocardial ischemia when complicated by coronary dissection, or evidence of tamponade physiology when pericardial effusion is present. Reverberation artifact can mimic a dissection flap. A true flap moves independently of the outer aortic wall which can be confirmed by M-mode. Color flow respects a true flap but does not respect a reverberation artifact. Assessment for bicuspid aortic valve (BAV) morphology should be done in systole, not diastole. In diastole, when the valve is closed, the raphé can make a bicuspid valve appear trileaflet. Doming in the parasternal long axis (PLAX) view and an eccentric closure line on PLAX M-mode should also raise suspicion for BAV.

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.

The Use of CT Imaging Technology in Peripherally Inserted Central Catheter

Objective: The objective is to explore the application of computed X-ray tomography (CT) imaging technology in peripherally inserted central catheter (PICC), and to propose a more effective method for PICC catheterization. Method: In this study, 69 subjects are divided into the observation group (X-ray and CT) and the control group (X-ray). The guiding effect of CT images on PICC tube placement in complex cases is compared. In this study, CT localization of the superior vena cava–caval-atrial junction (CAJ) is used as the gold standard. The position relationship of carina-CAJ and carina-PICC catheter tip is measured and analyzed by CT image and chest radiography (CXR) image, providing scientific basis for PICC tip imaging. Results: After this study, the tip of the catheter should be 1/3 of the middle and lower part of the superior vena cava, about 3 cm above the junction of the right atrium and the superior vena cava, and in the upper part of the diaphragm of the inferior vena cava, so that it cannot enter the right ventricle or the right atrium. The best position of the tip of the catheter is near the junction of the superior vena cava and the right atrium. The average vertical distance between the tracheal carina and CAJ is 4.79 cm. Conclusion: CT and X-ray examination can effectively determine the location of the tip of PICC catheter in cancer chemotherapy patients, but the clarity of X-ray examination is missing. It is suggested to adopt CT examination, and further adopt and promote it.

New Technique for Intrathoracic Implantation of Extraluminal Spiral Prostheses in the Trachea

Background: Extraluminal surgical procedures for intrathoracic tracheal collapse in dogs are not routinely performed. The patients are normally treated with different drugs or by intraluminal stents. However, in more severe cases, drug treatment does not always have good outcomes, and intraluminal prostheses can be correlated to several postoperative problems. In order to obtain better results, we aimed to develop a surgical technique for implantation of a new extraluminal helical prosthesis in the thoracic segment of the trachea through cervical access, associated with pneumatic mediastinoscopy for certification of the technique and minimization of possible complications.Materials, Methods &amp; Results: Seven canine corpses (CCs) from non-traumatic death, weighing between 2 and 7 kg, were used. A ventral cervical approach to the trachea was associated with blunt mediastinal dissection. Trans cervical pneumatic mediastinoscopy was used for evaluation of the dissection and location of the implant. These were compared with the necropsy findings by the exact Wilcoxon two-sample test, with P &lt; 0.05. The results of necropsy and mediastinoscopy did not present significant differences at P &lt; 0.05. During the examinations, the presence of some mediastinal visceral lesions caused by the prosthesis, the integrity of the mediastinum and possible lesions to RLN and blood vessels (BV) were analyzed. We also investigated the location of the distal part of the prosthesis in the thoracic segment of the trachea and its dissection. To evaluate the technique, statistical comparison was made between mediastinoscopy and necropsy findings. The data were compared by the Wilcoxon test at 5% probability. The tracheas of all CCs were efficiently dissected, but in some cases problems that can happen during the procedure were noticed. This was checked by mediastinoscopy and confirmed by necropsy. The median of the scores was 1 (good dissection and visualization), with variance of zero for mediastinoscopy and 0.14 for necropsy. In the mediastinoscopy of one CC, the prosthesis crossed the tracheal bifurcation, involving the posterior vessels of this region, which was confirmed by necropsy. However, the dissection showed no vascular lesions. The integrity of the mediastinum was assessed only by mediastinoscopy. There was no impairment caused by any of the procedures performed. This resulted in a median score of 1 (integrity) with zero variance. When the positioning of the prosthesis was evaluated in relation to the tracheal bifurcation, identical values were obtained by both methods. The median score was 1, with variance of 0.62. No statistical differences were found between the two evaluation methods for the analyzed variables. This demonstrates the strong potential of the proposed evaluation techniques.Discussion: Our results show that the execution of the technique is possible, but some complications may occur. Mediastinoscopy as an evaluation procedure can pose some complications, these considerations are important, but by using technique proposed in this study, these factors are minimized due to the ease of technical implantation of the extraluminal tracheal stent, without the need for several instruments competing in the inflated mediastinal space. We concluded that the technique is viable and a safe method with minimal invasion for investigation and treatment of mediastinal diseases, presenting low impairment of the paratracheal structures, and that mediastinoscopy can be used as a transoperative evaluation method to minimize complications.

Проведение бронхоскопа через искусственные дыхательные пути

The experience of 811 bronchoscopies (100%) was analysed in patients on artificial lung ventilation. The position of the intubation tube in the trachea during the procedure was assessed. In 78 cases (9,618%) there was an incorrect position of the intubation tube requiring correction. In 35 cases (4,316%), the intubation tube was displaced to the right main bronchus and as result, the left lung was not ventilated. In the remaining cases, various ways of the incorrect position of the intubation tube above the tracheal bifurcation carina were noted. As a recommendation, endoscopic criteria of the correct position of the intubation tube are suggested. For timely diagnostics and correction of such disturbances, it is recommended to perform obligatory bronchoscopic monitoring.

ARTERIAL AND VENOUS VASCULARIZATION OF THE LUNG IN AMERICAN MINK (NEOVISON VISON)

This paper presents a comprehensive anatomic overview of normal pulmonary vascularization in an American mink (Neovison vison), with emphasis on venous and arterial peculiarities as regards its course and potential disruptions. The study is designed as macro-morphological and vascular network analysis of lungs of fifteen minks of different age and gender. Dissection is conducted along with injection corrosion method in order to clearly visualize the vascular topology, bronchial tree, arterial and venous trees, and their interconnections. The specimens exhibit consistence in the arterial branching pattern with negligible range of alterations. It was noticed that upon leaving the right ventricle of heart, pulmonary trunk divides ventrally from the site of tracheal bifurcation. The divisions were identified as left and right pulmonary arteries, which then ramified in the left and right lung, respectively. Left a. pulmonalis further divides into two major branches ramus lobi cranialis and ramus lobi caudalis, while the right a. pulmonalis gives five major branches for lobes in the right lung. Total of five pulmonary veins leave pulmonary lobes and enter left atrium of the heart. Mink has a distinct niche in biomedical research, proving as a suitable model to enhance the understandings of the various diseases. Gained insights are valuable as reference values for examination of the vasculature in other Mustelidae species, recognition of potential deviations and vascular remodeling due to respiratory diseases.

Predictive value of chest CT scoring in COVID-19 patients in Wuhan, China: A retrospective cohort study

BackgroundComputed tomography (CT) findings of COVID-19 patients were demonstrated by cases series and descriptive studies, but quantitative analysis performed by clinical doctors and studies on its predictive value were rarely seen. The aim of the study is to analyze CT score in COVID-19 patients and explore its predictive value. Materials and methodsWe conducted a retrospective cohort study among confirmed COVID -19 patients with available CT images between February 8, 2020 and March 7, 2020. The lung was divided into six zones by the level of tracheal carina and the level of inferior pulmonary vein bilaterally on CT. Ground-glass opacity (GGO), consolidation, crazy-paving pattern and overall lung involvement were rated by Likert scale of 0–4 or binary as 0 or 1. Global severity score for each targeted pattern was calculated as total score of six zones. ResultsThere were 53 patients and 137 CT scans included in the study. There were 18(34%) of the patients classified as moderate cases while 35(66%) patients were severe/critical cases. Severe/critical patients had higher CT scores in several types of abnormalities than moderate patients from the second week to the fourth week post symptom onset. Overall lung involvement score in the second week demonstrated predictive value for severity with a sensitivity of 81.0% and specificity of 69.2%. ConclusionsOur modified semi-quantitative CT scoring system for COVID-19 patients demonstrated feasibility. Overall lung involvement score on the second week had predictive value for clinical severity and could be indicator for further treatment.

Anatomy of the right upper lobe revisited and clinical considerations in Chinese population.

ObjectiveThe anatomy of the tracheobronchial tree differs among not only various races but also individual ethnic groups. Different lengths of the right mainstem bronchus (RMSB) had been described in previous publications. Since the differences in the anatomy of the RMSB and right upper lobe bronchus (RUB) may have clinical relevance when selecting devices, specifically, the right-side double lumen tube (R-DLT) for lung isolation, we revisited the anatomy of the right upper lobe in a large scale Chinese population.MethodsIn this retrospective cohort study, we reviewed 2093 consecutive adult patients undergoing thoracic computed tomography (CT) scans from data base in our hospital. Demographic characteristics were collected. The lengths, internal diameters, and angles of the RMSB and RUB were measured using reconstructive CT images. The correlations between the demographic variables and the RMSB length and diameters were also analyzed.ResultsThe incidence of the aberrant RUB originated equal or above the tracheal carina was 8.1‰. 52.3% of the patients had a length of RMSB less than 23 mm, and the incidence of RMSB length <23 mm in women was significantly higher than that in men (63.5% vs. 42.8%, p = 0.000). The right bronchial length (RBL) was less than 10 mm in 21% of cases (17.8% in men and 24.8% in women, respectively, p = 0.000). Both the RMSB lengths and diameters had poor correlations with the heights in either male or female patients.ConclusionA much higher incidence of a shortened RMSB potentially make placement of a R-DLT more difficult in Chinese population. Both the lengths and diameters of the RMSB cannot be predicted by the height. Preoperative thoracic CT scan for each patient helps optimizing the selection of a lung isolation device, and the importance of an evaluation of the CT scans preoperatively by the anesthesiologists should be emphasized.

Total Lung-sparing Surgery for Tracheobronchial Low-grade Malignancies

Total lung-sparing tracheobronchial sleeve resections are a step forward in the treatment of low-grade bronchial tumors in which minimal resection margins are required to achieve complete control of the disease. This study retrospectively collected data on patients who underwent total lung-sparing procedures for low-grade tracheobronchial tumors at 2 thoracic surgical centers from January 1984 to October2019. The study included 98 patients, 46 -female (47%) and 52 -male (53%), with a median age of 39 years (range, 7 to 70 years). Thirty-four patients underwent operative endoscopy before surgery (32 had laser treatment, and 2 had endobronchial stenting). The surgical resections were as follows: 9 (9%), tracheal carina; 18 (18%), second carina; 31 (32%), left main bronchi; 25 (26%), right main bronchi; and 15 (15%), intermediate bronchus. The median length of the resected bronchus was 2.2 cm. The median postoperative in-hospital stay was 8 days, and no perioperative mortality was observed. Postoperative complications were recorded in 26-patients (27%). The final histologic classification was as follows: 37 typical carcinoids (38%); 10 atypical carcinoids (10%); 29 adenoid cystic carcinomas (30%); 15 mucoepidermoid carcinomas (15%); 6 inflammatory myofibroblastic tumors (6%); and 1 glomic tumor (1%). Twenty-two patients had positive resection margins and underwent adjuvant radiotherapy. Three patients with adenoid cystic carcinoma had recurrences (1 local and 2 systemic). After a median follow-up time of 54.5 months (range, 4 to 360 months), the overall actuarial 5-year survival was 97%. Total lung-sparing tracheobronchial sleeve resection for low-grade malignant disease requires advanced surgical skills, but the hospital morbidity and mortality are very low. This technique is adequate and safe for highly selected patients with low-grade endobronchial malignant diseases, and its use should be encouraged in experienced centers.

Tracheal development after left pulmonary artery reimplantation: an individual study

Pulmonary artery sling (PA sling) often presents as a life-threatening condition requiring urgent surgical correction. We reported 32 cases of PA sling in children who were followed up postoperatively in the past 6 years. All patients with PA slings who were admitted to the hospital from January 2012 to December 2017 and underwent surgery were retrospectively analyzed. The mean age of the 32 patients at repair was 16.97 months (range, 15 days to 128 months). Six patients required ventilator assistance for respiratory failure. All children underwent left pulmonary artery (LPA) reimplantation (n = 32), and 3 patients needed reimplantation slide tracheoplasty (n = 3) due to ventilation weaning failure. Four patients died, 27 patients survived until discharge, and 18 patients were followed up. Pulmonary computed tomography imaging and echocardiography were performed in 18 patients who were followed up. After LPA reimplantation, the tracheal carina area was significantly enlarged compared to that preoperation (p = 0.0002). In this follow-up cohort study, 75% of the patients who underwent LPA reimplantation survived until discharge. The survivors had subsequently well-developed pulmonary arteries and tracheas.

A NOVEL TREATMENT APPROACH FOR A RARE TRACHEAL TUMOR

SESSION TITLE: Fellows Procedures Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: The differential diagnosis for tracheal tumors is broad and often requires direct endobronchial evaluation for management. Neoplastic tumors account for 10% of tracheal masses. Herein, we describe a rare adult tracheal tumor that was successfully treated bronchoscopically. CASE PRESENTATION: A 48 year-old non-smoking female with childhood asthma presented to pulmonary clinic with a chronic cough for 4 months despite multiple courses of antibiotics and steroid bursts for suspected bronchitis. Due to persistent symptoms, she ultimately underwent a computed tomography scan of the chest which revealed a 0.9x0.6x0.5 cm polypoid-like density at the tracheal carina. Initial endobronchial biopsies showed inflammatory cells without evidence of malignancy. Due to concern for sampling artifact, she underwent a flexible/rigid bronchoscopy with tumor excision by snare electrocautery, argon plasma coagulation, and cryotherapy. Pathologic examination revealed an inflammatory myofibroblastic tumor (IMT) without an ALK rearrangement. A tumor board recommended curative tracheal resection versus surveillance bronchoscopy and imaging. The patient opted for surveillance as her symptoms had resolved. She has had annual bronchoscopies without any evidence of recurrence, and she remains asymptomatic. DISCUSSION: IMTs are slow growing quasi-neoplastic lesions that mostly affect children under 16 years old and are rarely reported in adults, accounting for 0.04-0.07% of all lung neoplasms. Most commonly affecting the lungs, these tumors can also involve a multitude of different organs. The etiology remains unknown although it is theorized to arise from an inflammatory process like a prior infection, trauma or surgery. However, the ALK rearrangement, which has been noted in 50% of IMTs, suggests a possible neoplastic origin. Classic pathologic features include myxoid spindle myofibroblasts with abundant inflammatory cells of plasma cells, lymphocytes, and eosinophils. Up to 80% of patients are asymptomatic but few may present with symptoms suggestive of, and commonly mistaken for, asthma. IMT treatment typically requires surgical resection via thorascoscopy or thoractomy. Chemotherapy, ALK directed therapies, and/or steroids have been used in nonsurgical cases. Few case reports have described effective bronchoscopic resection. A case series of 7 patients reported successful resection with one recurrence. Unfortunately, due to the tumor’s rarity, no robust studies exist for evaluating bronchoscopic treatment. A bronchoscopic approach offers a minimally invasive and potentially curative option but requires regular follow up for recurrence. CONCLUSIONS: IMTs are rare adult tracheal tumors, and treatment often entails surgical tracheal resection, which carries significant peri-operative risks with prolonged recovery. This case of IMT was successfully treated by bronchoscopic resection with curative effect. Reference #1: Jain S, Chopra P, Agarwal A, et al. Inflammatory myofibroblastic tumor of trachea. J Bronchol Intervent Pulmonol 2013;20:80-83. Reference #2: Oztuna F, Pehlivanlar M, Abul Y, et al. Adult inflammatory myofibroblastic tumor of the trachea: case report and literature review. Respir Care 2013;58:e72-6. DISCLOSURES: Speaker/Speaker's Bureau relationship with Boehringer-Ingelheim Pharmaceuticals Please note: $5001 - $20000 Added 04/07/2020 by Jaime Betancourt, source=Web Response, value=Honoraria Speaker/Speaker's Bureau relationship with Vapotherm, Inc Please note: $5001 - $20000 Added 04/07/2020 by Jaime Betancourt, source=Web Response, value=Honoraria No relevant relationships by Tao He, source=Web Response No relevant relationships by Leeyen Hsu, source=Web Response No relevant relationships by Scott Oh, source=Web Response

THE HIDDEN PARATHYROID: A RARE CASE OF ECTOPIC TRACHEOBRONCHIAL PARA-AORTIC PARATHYROID ADENOMA

SESSION TITLE: Medical Student/Resident Disorders of the Mediastinum Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Ectopic parathyroid glands arise due to abnormal embryological migration and are found in 1-3% of the population. They are mostly located in the anterior mediastinum near the thymus. It is difficult to identify the ectopic site even with advanced imaging modalities. We present a diagnostically challenging case of parathyroid adenoma in an unusual site. CASE PRESENTATION: A 77-year-old male with no significant medical history presented with abdominal discomfort and was noted to have hypercalcemia of 16mg/dl. The patient reported that he was in his usual state of health until a few months ago, when he developed abdominal pain, nausea, with occasional episodes of forgetfulness. On presentation, his vital signs were stable. Labs revealed hypercalcemia, ionized calcium 2.05 mmol/L, parathyroid hormone(PTH) 664pg/ml, normal thyroid-stimulating hormone, phosphorus 2mg/dl, and 25 hydroxyvitamin D 26ng/dl. After initial stabilization, he underwent neck ultrasonography(US) that was negative. Sestamibi scan revealed a soft tissue density abutting the posterior aspect of the thyroid. Subsequent computerized tomography(CT) scan of the neck revealed a 3mm lesion in the right intrathyroidal area suspicious for adenoma and the patient underwent right thyroidectomy with neck exploration. However, the exploration did not reveal an adenoma and the patient continued to have hypercalcemia. He had a repeat sestamibi scan and CT scan that demonstrated an arterial enhancing 1 cm nodule in the left paratracheal region close to the tracheobronchial angle, near the aortic arch. The patient underwent an endobronchial ultrasound with biopsy confirming the parathyroid adenoma and subsequently underwent a video-assisted thoracoscopic surgery(VATS) resection of ectopic parathyroid, with the resolution of hypercalcemia. DISCUSSION: Ectopic parathyroid glands are commonly found in the visceral compartment of the mediastinum, aortopulmonary window, or close to the right pulmonary artery near the tracheal bifurcation which makes the diagnosis challenging (1). Symptomatic mediastinal adenomas are rare accounting for 1% of operations for hyperparathyroidism. As the ectopic adenomas can be in varied locations, radiological assistance is pivotal for diagnosis, but sometimes imaging modalities also fail to identify the lesion. Accurate preoperative localization is the key to managing the disease. Sestamibi scan and neck US are first-line imaging modalities. Anterior mediastinal tumors are managed through a transcervical approach, and tumors at unusual sites might need VATS, sternotomy, or thoracotomy (2). CONCLUSIONS: It is vital to recognize ectopic parathyroid adenoma as a cause of hyperparathyroidism to prevent unnecessary interventions that increases the health care costs, and morbidity. In cases of persistent hypercalcemia due to hyperparathyroidism, ectopic hyperparathyroidism should be considered. Reference #1: Cupisti K, Dotzenrath C, Simon D, Roher HD, Goretzki PE. Therapy of suspected intrathoracic parathyroid adenomas. Experiences using open transthoracic approach and video-assisted thoracoscopic surgery. Langenbecks Arch Surg. 2002;386(7):488-93. Reference #2: Medrano C, Hazelrigg SR, Landreneau RJ, Boley TM, Shawgo T, Grasch A. Thoracoscopic resection of ectopic parathyroid glands. Ann Thorac Surg. 2000;69(1):221-3. DISCLOSURES: No relevant relationships by Dimitrios Drekolias, source=Web Response No relevant relationships by Naga Vaishnavi Gadela, source=Web Response No relevant relationships by Karthik Gonuguntla, source=Web Response No relevant relationships by Kamran Manzoor, source=Web Response No relevant relationships by Nikola Perosevic, source=Web Response No relevant relationships by MIlica Perosevic, source=Web Response

Evidence of early increased sialylation of airway mucins and defective mucociliary clearance in CFTR-deficient piglets

BackgroundBacterial colonization in cystic fibrosis (CF) lungs has been directly associated to the loss of CFTR function, and/or secondarily linked to repetitive cycles of chronic inflammation/infection. We hypothesized that altered molecular properties of mucins could contribute to this process. MethodsNewborn CFTR+/+ and CFTR−/− were sacrificed before and 6 h after inoculation with luminescent Pseudomonas aeruginosa into the tracheal carina. Tracheal mucosa and the bronchoalveolar lavage (BAL) fluid were collected to determine the level of mucin O-glycosylation, bacteria binding to mucins and the airways transcriptome. Disturbances in mucociliary transport were determined by ex-vivo imaging of luminescent Pseudomonas aeruginosa. ResultsWe provide evidence of an increased sialylation of CF airway mucins and impaired mucociliary transport that occur before the onset of inflammation. Hypersialylation of mucins was reproduced on tracheal explants from non CF animals treated with GlyH101, an inhibitor of CFTR channel activity, indicating a causal relationship between the absence of CFTR expression and the sialylation of mucins. This increased sialylation was correlated to an increased adherence of P. aeruginosa to mucins. In vivo infection of newborn CF piglets by live luminescent P. aeruginosa demonstrated an impairment of mucociliary transport of this bacterium, with no evidence of pre-existing inflammation. ConclusionsOur results document for the first time in a well-defined CF animal model modifications that affect the O-glycan chains of mucins. These alterations precede infection and inflammation of airway tissues, and provide a favorable context for microbial development in CF lung that hallmarks this disease.

LandmarkNet: a 2D digital radiograph landmark estimator for registration

BackgroundRadiation therapy requires precision to target and escalate the doses to affected regions while reducing the adjacent normal tissue exposed to high radiotherapy doses. Image guidance has become the start of the art in the treating process. Registering the digital radiographs megavoltage x ray (MV-DRs) and the kilovoltage digital reconstructed radiographs (KV-DRRs) is difficult because of the poor quality of MV-DRs. We simplify the problem by registering between landmarks instead of entire image information, thence we propose a model to estimate the landmark accurately.MethodsAfter doctors’ analysis, it is proved that it is effective to register through several physiological features such as spinous process, tracheal bifurcation, Louis angle. We propose the LandmarkNet, a novel keypoint estimation architecture, can automatically detect keypoints in blurred medical images. The method applies the idea of Feature Pyramid Network (FPN) twice to merge the cross-scale and cross-layer features for feature extraction and landmark estimation successively. Intermediate supervision is used at the end of the first FPN to ensure that the underlying parameters are updated normally. The network finally produces heatmap to display the approximate location of landmarks and we obtain accurate position estimation after non-maximum suppression (NMS) processing.ResultsOur method could obtain accurate landmark estimation in the dataset provided by several cancer hospitals and labeled by ourselves. The standard percentage of correct keypoints (PCK) within 8 pixels of estimation for the spinous process, tracheal bifurcation and Louis angle is 81.24%, 98.95% and 85.61% respectively. For the above three landmarks, the mean deviation between the predicted location of each landmark and corresponding ground truth is 2.38, 0.98 and 2.64 pixels respectively.ConclusionLandmark estimation based on LandmarkNet has high accuracy for different kinds of landmarks. Our model estimates the location of tracheal bifurcation especially accurately because of its obvious features. For the spinous process, our model performs well in quantity estimation as well as in position estimation. The wide application of our method assists doctors in image-guided radiotherapy (IGRT) and provides the possibility of precise treatment in the true sense.