Diffuse abnormalities of the trachea and main bronchi

Building and validating an artificial intelligence model to identify tracheobronchopathia osteochondroplastica by using bronchoscopic images

BACKGROUND

Given the rarity of tracheobronchopathia osteochondroplastica (TO), many young doctors in primary hospitals are unable to identify TO based on bronchoscopy findings.

OBJECTIVES

To build an artificial intelligence (AI) model for differentiating TO from other multinodular airway diseases by using bronchoscopic images.

DESIGN

We designed the study by comparing the imaging data of patients undergoing bronchoscopy from January 2010 to October 2022 by using EfficientNet. Bronchoscopic images of 21 patients with TO at Anhui Chest Hospital from October 2019 to October 2022 were collected for external validation.

METHODS

Bronchoscopic images of patients with multinodular airway lesions (including TO, amyloidosis, tumors, and inflammation) and without airway lesions in the First Affiliated Hospital of Guangzhou Medical University were collected. The images were randomized (4:1) into training and validation groups based on different diseases and utilized for deep learning by convolutional neural networks (CNNs).

RESULTS

We enrolled 201 patients with multinodular airway disease (38, 15, 75, and 73 patients with TO, amyloidosis, tumors, and inflammation, respectively) and 213 without any airway lesions. To find multinodular lesion images for deep learning, we utilized 2183 bronchoscopic images of multinodular lesions (including TO, amyloidosis, tumor, and inflammation) and compared them with images without any airway lesions (1733). The accuracy of multinodular lesion identification was 98.9%. Further, the accuracy of TO detection based on the bronchoscopic images of multinodular lesions was 89.2%. Regarding external validation (using images from 21 patients with TO), all patients could be diagnosed with TO; the accuracy was 89.8%.

CONCLUSION

We built an AI model that could differentiate TO from other multinodular airway diseases (mainly amyloidosis, tumors, and inflammation) by using bronchoscopic images. The model could help young physicians identify this rare airway disease.

Airway management for a patient with tracheobronchomegaly undergoing lobectomy: a case report

BACKGROUND

Tracheobronchomegaly (TBM) is a rare disorder mainly characterized by dilatation and malacia of the trachea and major bronchi with diverticularization. This will be a great challenge for airway management, especially in thoracic surgery requiring one-lung ventilation. Using a laryngeal mask airway and a modified double-lumen Foley catheter (DFC) as a "blocker" may achieve one-lung ventilation. This is the first report introducing this method in a patient with TBM.

CASE PRESENTATION

We present a 64-year-old man with TBM receiving left lower lobectomy. Preoperative chest computed tomography demonstrated a prominent tracheobronchial dilation and deformation with multiple diverticularization. The most commonly used double-lumen tube or bronchial blocker could not match the distorted airways. After general anesthesia induction, a 4# laryngeal mask was inserted, through which the modified DFC was positioned in the left main bronchus with the guidance of a fiberoptic bronchoscope. The DFC balloon was inflated with 10 ml air and lung isolation was achieved without any significant air leak during one-lung or two-lung ventilation. However, the collapse of the non-dependent lung was delayed and finally achieved by low-pressure artificial pneumothorax. The surgery was successful and the patient was extubated soon after the surgery.

CONCLUSIONS

Using a laryngeal mask airway with a modified double-lumen Foley catheter acted as a bronchial blocker could be an alternative method to achieve lung isolation.

A rare case of rapidly progressive Tracheobronchopathia Osteochondroplastica

Tracheobronchopathia Osteochondroplastica (TO) is a rare benign disorder that is seldom progressive. Here, we report a case diagnosed with TO in our hospital. Bronchoscopy revealed multiple cartilaginous and ossifying nodules that are diagnostic for TO. Nodules protruding into the airways were observed as widespread and extended by the repeat bronchoscopy after 2 months of the diagnosis. TO was confirmed with the histopathology of the biopsies from nodules. Then he was referred to an interventional pulmonologist for laser ablation.

A rare case of isolated laryngotracheal amyloidosis with airway narrowing and vocal fold involvement

Primary amyloidosis is a rare condition with 6-10 cases in a million, with focal involvement representing 9%-15% of those cases [1,2]. Isolated tracheobronchial amyloidosis is extremely rare and when present, can result in focal or diffuse thickening of the glottis, trachea and bronchi, leading to hoarseness, shortness of breath, and dysphonia. Computed tomography (CT) usually shows circumferential thickening of trachea and bronchi with or without calcifications and associated airway narrowing of affected segments. MRI demonstrates intermediate to low signal on T1, low signal on T2 and variable heterogeneous enhancement. Multiple conditions can result in thickening of the airway including but not limited to inflammatory, infectious, and neoplastic etiologies. Biopsy with histologic correlation provides a definitive diagnosis. Biopsied tissue demonstrates characteristic apple-green birefringence with Congo red stain. There is no cure for amyloidosis and the prognosis is quite variable depending on the extent of airway involvement. Current treatments are aimed at alleviating symptoms and include bronchoscopic debridement, laser therapy, and balloon dilation with adjuvant radiation therapy. Here, we present a rare case of a 47-year-old male with isolated laryngotracheal amyloidosis with marked airway narrowing and vocal fold involvement.

Tracheobronchitis in patients with diffuse wall thickening: Three case reports

We herein report the cases of three patients with chest symptoms or fever and diffuse wall thickening of the trachea and main bronchi on chest CT. They were diagnosed with various causes of inflammations of the trachea and main bronchi using bronchial or tracheal biopsy specimens and flexible bronchoscopy.

Coronavirus Disease 2019-Induced Tracheomegaly: A Case Report

Tracheomegaly is a medical condition where the tracheal diameter is greater than the upper limits of normal. Tracheomegaly can be classified as primary or secondary. Primary tracheomegaly is usually congenital. Secondary tracheomegaly can be due to multiple causes, including connective tissue disease, infections, autoimmune diseases like sarcoidosis, and prolonged mechanical ventilation. Here, we describe the first reported case of tracheomegaly secondary to coronavirus disease 2019 (COVID-19) pneumonia and COVID-induced interstitial lung disease (ILD). While many cases of tracheomegaly are asymptomatic, patients can have symptoms like cough, dyspnea, hemoptysis, or even respiratory failure. Tracheomegaly is associated with a higher risk of recurrent lower respiratory tract infections, chronic cough, bronchiectasis, and tracheobronchomalacia. Early recognition of COVID-19-induced tracheomegaly can help initial early management and reduce the incidence of infections.

CT features in amyloidosis of the respiratory system - Comprehensive analysis in a tertiary referral center cohort

PURPOSE

Amyloidosis of the respiratory system is rare and challenging since imaging findings have several more prevalent alternative diagnoses. We analyze and quantify chest CT findings in a large tertiary referral center patient cohort with confirmed amyloidosis of the respiratory system.

METHODS

67 patients with histology-proven amyloidosis of the respiratory system and with available chest CT scans were retrospectively enrolled (years 2002-2018): 41 patients with local pulmonary parenchymal, 20 with local tracheobronchial, and 6 with systemic amyloidosis. CT was scored for findings like mass lesions, nodules, cysts, lymphadenopathy, calcifications and pleural, interstitial and tracheobronchial manifestations. Clinical data and imaging findings' frequencies among patients with local pulmonary parenchymal and tracheobronchial amyloidosis were compared.

RESULTS

Patients with local pulmonary parenchymal amyloidosis were older (67 vs. 56 years; P = 0.013) and less frequently symptomatic for cough (24% vs. 70%; P = 0.018) and bronchopulmonal infections (7% vs. 55%; P < 0.001) than patients with tracheobronchial amyloidosis. Local pulmonary parenchymal amyloidosis showed higher frequency of mass-like lesions (41% vs. 0%; P = 0.002) and nodules (95% vs. 20%; P < 0.001, with 10 or more nodules in 56% vs. 0%; P < 0.001 and predominantly pleura-associated in 32% vs. 0%; P = 0.02). Tracheobronchial amyloidosis leads to wall thickening of the bronchi (100% vs. 5%; P < 0.001) and the trachea (70% vs. 2%; P < 0.001). Systemic amyloidosis went along with a predominant alveolar septal pattern in 4 out of 6 patients.

CONCLUSION

Patients with local pulmonary parenchymal amyloidosis differ significantly from patients with tracheobronchial amyloidosis regarding clinical data and CT findings' frequencies. Being familiar with radiological manifestations of all three respiratory amyloidosis distribution patterns is essential to accelerate the diagnosis.

Tracheobronchopathia Osteochondroplastica: Five Cases Report and Literature Review

Tracheobronchopathia osteochondroplastica (TO) is a rare disease. Here, we report 5 TO cases treated at our hospital. Bronchoscopy showed typical multiple firm and glossy nodules in all the 5 cases. Conservative treatment effectively alleviated the symptoms. Tracheobronchopathia osteochondroplastica is a manageable disease. Awareness in clinicians is critical to avoid unnecessary treatment in patients with TO.

Difficult intubation in an asymptomatic patient with tracheobronchopathia osteochondroplastica

Tracheobronchopathia osteochondroplastica (TO) is a rare, benign, slowly progressive disease of unknown aetiology. It is characterized by numerous sessile, cartilaginous, or osseous submucosal nodules distributed throughout the anterolateral walls of the trachea and projecting into the laryngotracheobronchial lumen. The diagnosis is usually incidental with distinct bronchoscopic or computed tomography (CT) scan findings. We have identified a case of asymptomatic TO through fibreoptic bronchoscopy and biopsy after having a difficult intubation for elective prostate surgery.

Non-neoplastic pathology at the crossroads between neck imaging and cardiothoracic imaging

The thoracic inlet is located at the crossroads between imaging of the neck and chest. It represents an important anatomic landmark, serving as the central conducting pathway for many vital structures extending from the neck into the chest and vice versa. Many important body systems are located within this region, including the enteric, respiratory, vascular, lymphatic, neurologic, and endocrine systems. A detailed examination of this region is essential when reviewing neck and thoracic imaging. This article will discuss the normal anatomic boundaries of the thoracic inlet and present an image-rich systematic discussion of the non-neoplastic pathology that can occur in this region. The neoplastic pathology of the thoracic inlet will be covered in a companion article.

Tracheobronchopathia osteochondroplastica

Tracheobronchopathia osteochondroplastica is a rare benign disease, of unknown cause, characterized by numerous sessile, cartilaginous, or bony submucosal nodules distributed throughout the anterolateral walls, projecting into the laryngotracheobronchial lumen. In general, tracheobronchopathia osteochondroplastica is diagnosed incidentally during bronchoscopy or autopsy and is not associated with a specific disease. We report the case of a male patient who was diagnosed with tracheobronchopathia osteochondroplastica via bronchoscopy and biopsy.

Multidimensional evaluation of tracheobronchial disease in adults

The large airways can be affected by a wide spectrum of acquired benign and malignant diseases. These lesions may present as focal or diffuse processes and with narrowing or widening of the airway. Some of these may be asymptomatic for quite some time and may be incidentally detected on imaging, while others may be symptomatic, causing airway compromise. There may be a characteristic radiograph and computed tomography (CT) appearance, suggesting a narrow differential. When the imaging findings are not definitive, tissue may be obtained for pathological analysis. It behooves the radiologist to be familiar with the pathologic findings that correlate with the radiographic or CT appearance of the most frequently seen large airway lesions. In this way, we may improve our diagnostic accuracy. This paper will present the imaging findings of the most prevalent tracheobronchial lesions along with any associated pathology. Teaching Points • The large airways can be affected by many acquired benign and malignant diseases.• Large airway lesions may present as focal or diffuse processes, with narrowing or widening.• There may or may not be characteristic imaging appearance of large airway disease.• If imaging findings are not definitive, tissue may be obtained for pathological analysis.

Helical computed tomography scanning of the larynx and upper trachea in rabbits

Background

Computed tomography (CT) is used to evaluate the human tracheobronchial tree because of its unsurpassed ability to visualize the airway and surrounding structures. To establish an ideal animal model for studying subglottic stenosis, we assessed the size and morphology of the normal rabbit’s laryngotracheal airway by helical CT. We measured luminal dimensions at the levels of the arytenoid and cricoid cartilages and the first, third, and eighth tracheal rings. At all levels, the axial slices were used to calculate the maximum anteroposterior (AP) dimension, transverse dimension, and cross-sectional areas. We measured the tracheal length from the cricoid to the third and eighth tracheal rings on sagittal reformation. We assessed the hyoid, thyroid, cricoid, arytenoid, and tracheal rings for the presence of calcific or soft tissue densities. We also addressed the presence or absence of pre-epiglottic and paraglottic fat.

Results

The mean AP tracheal dimension ± standard deviation (SD) was 8.6 ± 0.5 mm at the arytenoid level, 8.2 ± 0.7 mm at the cricoid level, and 7.7 ± 0.2 mm at the first tracheal ring level. The transverse tracheal dimension ±SD was 5.3 ± 0.1 mm at the arytenoid level, 5.5 ± 0.5 mm at the cricoid level, and 6.1 ± 0.6 mm at the first tracheal ring level. The mean tracheal area ±SD was 35.7 ± 2.2 mm² at the arytenoid level, 35.8 ± 5.1 mm² at the cricoid level, and 39.2 ± 4.3 mm² at the first tracheal ring level. The tracheal length ±SD was 10.7 ± 2.3 mm from the cricoid to the third tracheal ring and 19.1 ± 1.14 mm to the eighth tracheal ring. There was complete calcification of the hyoid in all rabbits. Only two rabbits showed complete thyroid, arytenoid, or tracheal ring calcification. The remaining airway components were otherwise either uncalcified or partially calcified. The uvula, epiglottis, aryepiglottic fold, vallecula, piriform sinus, true/false vocal cords, and pre-epiglottic/paraglottic fat were not seen in any rabbit.

Conclusions

Helical CT investigation provides good, highly definitive anatomic details of the larynx and trachea in rabbits. Such results may be used in further evaluation of the normal airway and in cases of subglottic stenosis.

Imaging of Large Airways Disorders

OBJECTIVE

Recent technical advances, including the routine use of CT thin sections and techniques such as 2D minimum-intensity-projection and 3D volume images, have increased our ability to detect large airways diseases. Furthermore, dedicated CT protocols allow the evaluation of dynamic airway dysfunction.

CONCLUSION

With diseases of the large airways more commonly seen in daily practice, it is important that radiologists be familiar with the appearances, differential diagnosis, and clinical implications of these entities.

Tracheobronchopathia osteochondroplastica: a review of the literature

BACKGROUND

Tracheobronchopathia osteochondroplastica (TBPOCP) is an uncommon benign condition affecting the lumen of tracheobronchial tree and characterized by abnormal chondrification and ossification. TBPOCP is more frequent than it has been reported, as it can be asymptomatic or present with non-specific respiratory symptoms.

AIMS

In this article, we provide a review of the English literature on the condition and discuss its clinical features, general principles, diagnostic approaches and current treatment recommendations for TBPOCP.

METHODS

We searched for all papers indexed in Science Citation Index and Science Citation Index - Expanded by using Thomson Reuters Web of Knowledge Web of Science software.

RESULTS

We reviewed a total of 72 scientific publications.

CONCLUSION

In order to highlight, diagnosis, treatment and treatment outcomes of TBPOCP, further review articles and large case series about this orphan disease are needed.

An interesting case of relapsing polychondritis in a young girl

Relapsing polychondritis is an acute, recurrent and progressive inflammation and degeneration of cartilage and connective tissue including that within the tracheobronchial tree affecting men and women equally and usually in the middle age. Serious airway manifestations occur in at least half of these patients. We present to you an interesting case report of a 20-year-old female who presented with exertional breathlessness. Imaging revealed diffuse calcification of pinna and tracheobronchial tree. Based on the characteristic clinical features and imaging studies a diagnosis of relapsing polychondritis was attained.

The relationships between tracheal index and lung volume parameters in mild-to-moderate COPD

BACKGROUND

Although elongated morphological changes in the trachea are known to be related to lung function in chronic obstructive pulmonary disease (COPD), whether the tracheal morphological changes are associated with airflow limitations or overinflation of the lung in the early stages of COPD has not yet been determined. Thus, our aim was to investigate the association of tracheal index (TI) with lung function parameters, including lung volume parameters, in COPD patients with mild-to-moderate airflow limitations.

MATERIALS AND METHODS

A retrospective study was conducted in 193 COPD patients with GOLD grades 1-2 (post-bronchodilator forced expiratory volume in 1s [FEV1] ≥ 50% predicted with FEV1/forced vital capacity ratio ≤ 70%; age range, 40-81) and 193 age- and gender-matched subjects with normal lung function as a control group (age range, 40-82). Two independent observers measured TI at three anatomical levels on chest radiographs and CT scans.

RESULTS

Compared with the control group, TI was reduced significantly and "saber-sheath trachea" was observed more frequently in COPD patients. Patients with GOLD grade 2 disease had a lower TI than those with GOLD grade 1. TI had apparent inverse correlations with total lung capacity, functional residual capacity, and residual volume, regardless of the anatomical level of the trachea. Even after adjustments for covariates, this association persisted.

CONCLUSIONS

TI is reduced even in mild-to-moderate COPD patients, and TI measured on chest CT shows significant inverse relationships with all lung volume parameters assessed, suggesting that tracheal morphology may change during the early stages of COPD.

3-D printouts of the tracheobronchial tree generated from CT images as an aid to management in a case of tracheobronchial chondromalacia caused by relapsing polychondritis

This report concerns a 67 year old male patient with known advanced relapsing polychondritis complicated by tracheobronchial chondromalacia who is increasingly symptomatic and therapeutic options such as tracheostomy and stenting procedures are being considered. The DICOM files from the patient's dynamic chest CT in its inspiratory and expiratory phases were used to generate stereolithography (STL) files and hence print out 3-D models of the patient's trachea and central airways. The 4 full-sized models allowed better understanding of the extent and location of any stenosis or malacic change and should aid any planned future stenting procedures. The future possibility of using the models as scaffolding to generate a new cartilaginous upper airway using regenerative medical techniques is also discussed.

Tracheobronchopathia osteochondroplastica--a rare or an overlooked entity?

Tracheobronchopathia osteochondroplastica is an idiopathic non-malignant disease of large airways featured by submucosal cartilaginous to osseous nodules overlying the cartilaginous rings, which may be focal or diffuse. Clinical presentation varies from asymptomatic to symptoms like breathlessness, recurrent chest infections, cough and hemoptysis. Due to the lack of awareness of this disease, it remains an under recognized entity. We are describing the computed tomography and bronchoscopic findings of two recently diagnosed cases at our institute. The purpose of this report is to familiarize radiologists with imaging appearance of this condition, with the goal of increasing clinical suspicion of this uncommon condition.

Multidetector-row Computed Tomography of Diffuse Tracheal Disease: Pictorial Review

Diffuse tracheal diseases are uncommon and may mimic asthma or other forms of chronic obstructive lung disease. Bronchoscopy is usually definitive in establishing a diagnosis and assessing the severity of diffuse tracheal disease. However, advances in multidetector-row computed tomography (MDCT) technology allow for rapid acquisition time and generation of high-quality multiplanar reconstructions and virtual bronchoscopic images, making MDCT evaluation of suspected or known tracheal disease the noninvasive examination of choice. The MDCT findings of the various diseases that diffusely affect the trachea may be highly suggestive of 1 particular disease or narrow the differential diagnosis to a few possibilities. Moreover, MDCT imaging of the chest can help identify associated lung disease or complications of diffuse tracheal disease such as pneumonia or atelectasis. This pictorial review illustrates the MDCT appearances of the more common diffuse tracheal diseases.

Case report: Mounier-Kuhn syndrome

Tracheobronchomegaly or Mounier-Kuhn syndrome is a rare disorder characterized by marked dilatation of the trachea and main bronchi, bronchiectasis, and recurrent respiratory tract infections. The etiology of this disorder is uncertain and the clinical presentation is variable. The diagnosis is usually made on the basis of the characteristic CT scan findings. We report a case in a 21-year-old man presenting with recurrent lower respiratory tract infections.

A case of tracheal varices: an unusual but important cause of mural nodules in the trachea

Tracheal varices (TV) are uncommon but can be an important source of massive or recurrent haemoptysis. We present a case of TV in a 32-year-old patient with a history of Glenn-Fontan surgery, for congenital tricuspid atresia, and portal hypertension owing to cardiac cirrhosis. We discuss TV presenting as tracheal nodules in the presence of extensive mediastinal collateral circulation.

Multimodality bronchoscopic [corrected] imaging of tracheopathica osteochondroplastica

Results of a commercial optical coherence tomography system used as part of a multimodality diagnostic bronchoscopy platform are presented for a 61-year-old patient with central airway obstruction from tracheopathica osteochondroplastica. Comparison to results of white-light bronchoscopy, histology, and endobronchial ultrasound examination are accompanied by a discussion of resolution, penetration depth, contrast, and field of view of these imaging modalities. White-light bronchoscopy revealed irregularly shaped, firm submucosal nodules along cartilaginous structures of the anterior and lateral walls of the trachea, sparing the muscular posterior membrane. Endobronchial ultrasound showed a hyperechoic density of 0.4 cm thickness. optical coherence tomography (OCT) was performed using a commercially available, compact time-domain OCT system (Niris System, Imalux Corp., Cleveland, Ohio) with a magnetically actuating probe (two-dimensional, front imaging, and inside actuation). Images showed epithelium, upper submucosa, and osseous submucosal nodule layers corresponding with histopathology. To our knowledge, this is the first time these commercially available systems are used as part of a multimodality bronchoscopy platform to study diagnostic imaging of a benign disease causing central airway obstruction. Further studies are needed to optimize these systems for pulmonary applications and to determine how new-generation imaging modalities will be integrated into a multimodality bronchoscopy platform.

Relapsing polychondritis and airway involvement

OBJECTIVE

To assess the prevalence and characteristics of airway involvement in relapsing polychondritis (RP).

METHODS

Retrospective chart review and data analysis of RP patients seen in the Rheumatology Clinic and the Complex Airway Center at Beth Israel Deaconess Medical Center from January 2004 through February 2008.

RESULTS

RP was diagnosed in 145 patients. Thirty-one patients had airway involvement, a prevalence of 21%. Twenty-two patients were women (70%), and they were between 11 and 61 years of age (median age, 42 years) at the time of first symptoms. Airway symptoms were the first manifestation of disease in 17 patients (54%). Dyspnea was the most common symptom in 20 patients (64%), followed by cough, stridor, and hoarseness. Airway problems included the following: subglottic stenosis (n = 8; 26%); focal and diffuse malacia (n = 15; 48%); and focal stenosis in different areas of the bronchial tree in the rest of the patients. Twelve patients (40%) required and underwent intervention including balloon dilatation, stent placement, tracheotomy, or a combination of the above with good success. The majority of patients experienced improvement in airway symptoms after intervention. One patient died during the follow-up period from the progression of airway disease. The rest of the patients continue to undergo periodic evaluation and intervention.

CONCLUSION

In this largest cohort described in the English language literature, we found symptomatic airway involvement in RP to be common and at times severe. The nature of airway problems is diverse, with tracheomalacia being the most common. Airway intervention is frequently required and in experienced hands results in symptom improvement.

Neurofibromatosis type 1 with tracheobronchial neurofibromas: case report with emphasis on tomographic findings

A 65-year-old man with neurofibromatosis type 1 (NF-1) presented with a 3-month history of dyspnea and cough. The chest spiral computed tomography scan showed multiple neurofibromas in the larynx and tracheobronchial tree. Bronchoscopy was performed and the biopsy confirmed the diagnosis of benign neurofibroma. The upper airway involvement in NF-1 is rare, and the diagnosis on the basis of the clinical manifestation may be difficult. The clinical manifestations of patients with tracheobronchial neurofibromas are mostly related to airway obstruction, presenting with cough, wheezing, and dyspnea. Our case illustrates the value of spiral computed tomography imaging in providing an excellent anatomic definition of this rare manifestation of NF.

Alterações difusas da traquéia: aspectos na tomografia computadorizada

O objetivo deste ensaio pictórico foi apresentar as principais alterações tomográficas observadas em doenças que acometem a traquéia de forma difusa. As doenças estudadas foram amiloidose, traqueobroncopatia osteocondroplástica, traqueobroncomegalia, papilomatose laringo-traqueo-brônquica, linfoma, neurofibromatose, policondrite recidivante, granulomatose de Wegener, tuberculose, paracoccidioidomicose e traqueobroncomalácia. O principal aspecto observado na tomografia computadorizada foi o espessamento das paredes traqueais, com ou sem nodulações, calcificações parietais ou comprometimento da parede posterior. Embora a tomografia computadorizada permita a detecção e a caracterização das doenças das vias aéreas centrais, e a correlação com os dados clínicos reduza as possibilidades diagnósticas, a broncoscopia com biópsia continua sendo o procedimento mais importante no diagnóstico das lesões difusas da traquéia.

[Volume CT: recent advances in acquired abnormalities of the trachea]

OBJECTIVES

To show the recent improvements in CT imaging of the trachea due to the introduction of multidetector computed tomography (MDCT).

MATERIAL AND METHODS

MDCT technology, which was introduced in the early 00's, allows acquiring the entire airways within few seconds while using low dose parameters thanks to the natural high contrast of the airways.

RESULTS

Volume acquisition with isotropic voxels offers an excellent anatomical resolution in all directions, improving the quality of multiplanar reformations and 3D reconstructions, including virtual bronchoscopy. Therefore, the ability of CT for detecting and localizing tracheal abnormalities are improved, which is useful for planning endoscopy or open surgery, or assess their results. Dynamic acquisition during expiration is the last refinement permitted by MDCT, which is of value to detect tracheomalacia.

CONCLUSIONS

MDCT is a non-invasive technique to image the trachea. Its applications are numerous, such as depiction of anatomical or functional abnormalities, evaluation of local extent of the disease, planning and assessing open surgery or interventional endoscopy.

Relapsing Polychondritis: Prevalence of Expiratory CT Airway Abnormalities

PURPOSE

To retrospectively determine the prevalence of expiratory computed tomographic (CT) abnormalities, including malacia and air trapping, in patients with relapsing polychondritis and to retrospectively determine the frequency with which expiratory abnormalities are accompanied by inspiratory abnormalities on CT scans.

MATERIALS AND METHODS

Institutional review board approval was obtained, and informed consent was not required for this retrospective HIPAA-compliant study. A computerized hospital information system was used to identify all patients with clinically diagnosed or biopsy-proved relapsing polychondritis who were referred for CT airway imaging during a 17-month period. The study cohort comprised 18 patients (15 women, three men; mean age, 47 years; age range, 20-71 years). Multidetector helical CT was performed in all patients by using a standard protocol, which included end-inspiratory and dynamic expiratory volumetric imaging. Two observers who were blinded to the original scan interpretations simultaneously reviewed CT scans. Findings were recorded in consensus. Dynamic expiratory CT scans were assessed for malacia that involved the trachea and main bronchi (reduction in cross-sectional area of more than 50%) and for air trapping (failure of lung parenchyma to increase in attenuation during expiration). Air trapping was visually classified according to pattern and extent (lobular, segmental, lobar, or whole lung). Inspiratory CT scans were evaluated for tracheal and bronchial stenosis (>25% luminal diameter narrowing compared with a corresponding uninvolved segment), wall thickening (>2 mm), and calcification.

RESULTS

Expiratory CT abnormalities were present in 17 (94%) of 18 patients and included malacia in 13 patients (72%) and air trapping in 17 patients (94%). Inspiratory CT abnormalities were found in eight (47%) of 17 patients who had expiratory CT abnormalities. Calcification of the airway walls was present in seven (39%) of 18 patients. All patients who had inspiratory CT abnormalities demonstrated expiratory CT abnormalities.

CONCLUSION

Expiratory CT abnormalities were present in the majority of patients with relapsing polychondritis who were referred for airway imaging, yet only half of these patients demonstrated abnormalities on routine inspiratory CT scans. Thus, dynamic expiratory CT should be a standard component of imaging assessment in patients with relapsing polychondritis.

Tracheobronchopathia osteoplastica: cause of difficult tracheal intubation

Tracheobronchopathia osteochondroplastica is a rare benign disorder affecting the trachea and the bronchi. We report a case presenting as difficulty during tracheal intubation. Chest roentgenogram revealed nothing before surgery. Findings on computed tomographic imaging scans show calcified nodular densities protruding into the tracheal lumen, with an abnormally irregular tracheal morphology and decreased lateral diameter. The fiber optic bronchoscopy, which was unable to pass more than 4 to 5 cm, showed enormous prominent protrusion with significant narrowing of the tracheal lumen. The diagnosis was confirmed by virtual bronchoscopy, which showed a tracheal narrowing with a beaded appearance and an irregular border that extended into the trachea and main bronchi.

Síndrome de Mounier-Kühn

A síndrome de Mounier-Kühn, ou traqueobroncomegalia congênita, é uma entidade clínica rara caracterizada pela dilatação anormal de traquéia e brônquios principais. O diagnóstico geralmente pode ser realizado através da mensuração do diâmetro traqueal. Os autores apresentam o caso de um homem de 40 anos com pneumonia refratária ao tratamento, no qual a traqueobroncomegalia foi confirmada através de tomografia computadorizada.

Relapsing polychondritis affecting the lower respiratory tract

OBJECTIVE

The purpose of this study was to describe the CT findings of lower respiratory tract involvement by relapsing polychondritis.

CONCLUSION

The most common CT manifestations were increased attenuation and smooth thickening of airway walls. Tracheal or bronchial stenosis was less common. Airway collapse and lobar air trapping were seen in half of patients examined with expiratory CT.

Fibrosing Mediastinitis

Fibrosing mediastinitis is a rare benign disorder caused by proliferation of acellular collagen and fibrous tissue within the mediastinum. Although many cases are idiopathic, many (and perhaps most) cases in the United States are thought to be caused by an abnormal immunologic response to Histoplasma capsulatum infection. Affected patients are typically young and present with signs and symptoms of obstruction or compression of the superior vena cava, pulmonary veins or arteries, central airways, or esophagus. There may be two types of fibrosing mediastinitis: focal and diffuse. The focal type usually manifests on computed tomographic (CT) or magnetic resonance (MR) images as a localized, calcified mass in the paratracheal or subcarinal regions of the mediastinum or in the pulmonary hila. The diffuse type manifests on CT or MR images as a diffusely infiltrating, often noncalcified mass that affects multiple mediastinal compartments. CT and MR imaging play a vital role in the diagnosis and management of fibrosing mediastinitis.