normal pattern of tracheal branching in pigs, consists of an accessory bronchus to all or a portion of the right upper lobe that arises from the lateral tracheal wall within 2cm of tracheal carina
tracheal bronchus or bronchus suis
tracheal bronchus most often supplies what lung segment
right upper lobe
characterized by atresia of a segmental or subsegmental bronchus with a normal distal airway
bronchial atresia
caused by congenital or acquired abnormalities of the elastic membrane or cartilaginous rings of the trachea
focal tracheal dilatation
aka paratracheal air cysts, which may be congenital or acquired
tracheoceles
tracheoceles occur almost exclusively in the______ trachea because the pressure gradient from the extrathoracic trachea to the atmosphere with the Valsalva maneuver favors their formation in this region
cervical
circular lucencies along the right posterolateral trachea at the thoracic inlet in CT may represent
tracheoceles
most common cause of extrinsic mass effect on the trachea is a
tortuous or dilated aortic arch or brachiocephalic artery
Presents as a typical hourglass deformity of trachea on frontal radiography
Tracheal stenosis
Patients with extrathoracic tracheomalacia, most often at the site of a prior tracheostomy, demonstrate tracheal narrowing on inspiration or expiration?
Inspiration
Patients with intrathoracic tracheomalacia usually from prior endotracheal intubation, have tracheal narrowing on inspiration or expiration?
Expiration
This entity can produce a necrotizing granulomatous inflammation of the tracheal and central bronchi, leading to focal cervical narrowing, or in advanced disease, narrowing of the entire length of trachea. Its diagnosis is made by radiographic demonstration of tracheal narrowing in association with upper airway and renal involvment and characteristic findings on biopsy
Granulomatosis with polyangitis
Endotracheal and endobronchial tb are usually associated with
Cavitary tb
tracheal scleroma is a chronic granulomatous disorder caused by infection with
Klebsiella rhinoscleromatis
diffuse tracheal narrowing may be seen with what tracheal conditions
saber-shealth trachea, amyloidosis, tracheobronchopathia, osteochondroplastica, relapsing polychondritis, GPA or tracheal scleroma
can cause diffuse tracheal narrowing but is mostly seen in the cervical trachea
GPA or tracheal scleroma
rare condition in which there is incomplete septation of the cartilage rings, producing a long segment tracheal narrowing or “napkin ring” trachea
congenital tracheal stenosis
congenital tracheal stenosis is often associated with other congenital cardiovascular anomalies in particular,
anomalous origin of left PA from right PA (PA sling)
a fixed deformity of the intrathoracic trachea in which the coronal diameter is diminished to less than 2/3 of the sagittal diameter
saber-sheath trachea
saber sheath trachea commonly affects
older men with COPD
causes mass-like circumferential deposits that irregularly narrow the tracheal lumen seen in CT. It is characterized by deposition of a fibrillar protein polysaccharide complex in various organs
amyloidosis
rare disorder characterized by the presence of multiple submucosal osseous and cartilaginous deposits within the trachea abd central bronchi or elderly men. the lesions arise as enchondromas from the tracheal and bronchial cartilage, and then project internally to produce nodular submucosal deposits that irregularly narrow the tracheal tumen and have a characteristic appearance and feel on bronchoscopy
tracheobronchopathia osteochondroplastica
helpful feature in tracheobronchopathia osteochondroplastica that distinguishes this from tracheobronchial amyloid
calcified plaques that can be seen involving the anterior and lateral walls of trachea, with sparing of membranous posterior walls of the trachea which lacks cartilage
common associated finding in saber-sheath trachea
upper lobe emphysema
systemic autoimmune disorder that commonly affects the cartilage of the earlobes, nose, larynx, tracheobronchial tree, joints and large elastic arteries
relapsing polychondritis
early in the disease, tracheal wall inflammation associated with cartilage destruction leads to an abnormally compliant and dilated trachea. Later in the disease, fibrosis leads to diffuse fixed narrowing of trachal lumen
relapsing polychondritis
diagnosis is made by noting recurrent inflammation at two or more cartilaginous sites, most commonly the pinnae of the ear (producing cauliflower ears) and the bridge of the nose (producing saddle nose deformity)
relapsing polychondritis
congenital disorder of the elastic and smooth muscle components of the tracheal wall
tracheobronchomegaly (Mounier-Kuhn syndrome)
tracheobronchomegaly is associated with
ehler-danlos syndrome
In tracheobronchomegaly, trachea and central bronchi meaures
Greater than 3.0 and 2.5 cm respectively in coronal diameter
Congenital or acquired defect of tracheal cartilage causing soft ess of tracheal cartilage rings and a tendency for airway collapse
Tracheobronchomalacia
Congenital disorders most often associated with tracheobronchomalacia
Relapsing polychondritis, ehler danlos syndrome, mucopolysaccharidosis
May result from prolonged intubation, prior tracheostomy and extrinsic tracheal compression by mediastinal masses and vascular anomalies
Tracheobronchomegaly
Excessive airway collapse of trachea on expiration, seen best on dynamic expiratory CT using low dose CT acquisition performed during forced expiratory maneuver are imaging features of
Tracheobronchomegaly
A reduction in the cross-sectional area of the trachea exceeding 50% on the expiratory CT, particularly if there is a crescentic “frown-like” configuration to the trachea in cross section should suggest what diagnosis
Tracheobronchomegaly
“Lunate”-shaped trachea, in which the coronal diameter of the trachea exceeds the sagittal diameter on axial CT obtained at normal inspiration
Tracheobronchomegaly
Tracheal and bronchial fractures generally involve what part of bronchial tree
Proximal main bronchi (80%) or distal trachea (15%) within 2cm from the carina
Most common form of tracheal and bronchial injury
Horizontal laceration or transection parallel to the tracheo bronchial cartilage
Presence of calcified material within the tracheobronchial tree, develops from the erosion of a calcified peribronchial lymph node into the bronchial lumen
Broncholithiasis
Broncholiths may occlude the airway and lead to
Bronchiectasis, obstructive atelectasis or pneumonia
Diseases known collectively as COPD include
Asthma, chronic bronchitis, bronchiectasis and emphysema
Common pathophysiology in COPD
Obstruction to expiratory airflow
Airway disorder charcterized by rapid onset of bronchial narrowing with spontaneous resolution or improvement as a result of therapy
Asthma
Radiographic findings in uncomplicated asthma are primarily the result of
Diffuse airway narrowing
Results from excessive production of IgE following exposure to antigenic stimuli, resulting in bronchial smooth muscle contraction, bronchial wall inflammation, excessive mucus production
Asthma
Hyperinflation producing increased lung volume, flattening or inversion of the diaphragm, attenuation of the peripheral vascular markings and prominence of retrosternal airspace is the result of
Expiratory air trapping
Bronchial wall inflammation and thickening appear radiographically as
Peribronchial cuffing and tram tracking
Defined as the excess production and expectoration of sputum that occurs on most days for atleast 3 consecutive months in at leasr 2 consecutive years
Chronic bronchitis
Commonly affected lobes in chronic bronchitis
Lower lobe bronchi
Abnormal permanent dilatation of bronchi
Bronchiectasis
3 morphologic groups of bronchiectasis
Cylindrical, varicose, cystic (saccular)
Type of bronchiectais Characterized by mild diffuse dilatation of the bronchi
Cylindrical
Cystic bronchial dilatation interrupted by focal areas of narrowing, an appearance that has been likened to a string of pearls
Varicose bronchiectasis
Appears as clusters of bronchi with marked localized saccular dilatation
Cystic bronchiectasis
Characteristic appearance of multiple peripheral thin-walled cysts, with or without air-fluid levels that tend to cluster together in the distribution of a bronchovascular bundle is seen in
Ctstic bronchiectasis
Bronchiectatic changes are usually central or peripheral?
Peripheral
Central bronchiectasis is seen only in
Allergic bronchopulmonary aspergillosis, cystic fibrosis, bronchial atresia, acquired central bronchial obstruction
Triad of kartagener syndrome
Sinusitis, situs inversus, bronchiectasis
Post infectious bronchiectasis results from severe childhood pneumonia, usually from what organisms or viruses
Adenovirus, measles, pertussis
Allergic bronchopulmonary aspergillosis represents a hypersensitivity reaction to aspergillus antigens and is characterized clinically by
Asthma, blood eosinophilia, bronchiectasis, with mucus plugging and circulating antibodies to aspergillus antigen
Term used to describe the effect of severe pulmonary fibrosis on the peripheral airways
Traction bronchiectasis
Traction bronchiectasis occurs commonly in what lobes
Upper lobes
Defined as an abnormal, permanent enlargement of the airspaces distal to the terminal bronchiole, accompanied by destruction of alveolar walls and without obvious fibrosis
Emphysema
Most common emphysema and is characterized by airspace distension in the central portion of the lobule, with sparing of the more distal portions of the lobule
Centrilobular emphysema
Centrilobular emphysema affects what lobe
Upper lobes more than the lower lobes
Results in uniform distention of the airspaces throughout the substance of the lobule, from the central respiratory bronchioles to the peripheral alveolar sacs and alveoli
Panlobular emphysema
Panlobular emphysema has predilection to what lobe
Lower lobes
Seen as selective distention of peripheral airspaces adjacent to interlobular septa, with sparing of the centrilobular region. It is most often seen in the immediate subpleural regions of upper lobes
Paraseptal emphysema
Type of emphysema that may coalesce to form apical bullae; rupture of these bullae into the pleural space may give rise to spontaneous pneumothoraces
Paraseptal emphysema
Refers to destruction of lung tissue associated with fibrosis that bears no consistent relationship to a given portion of the lobules
Paracicatricial or irregular emphysema
Form of emphysema that is most often seen in association with old granulomatous inflammation
Paracicatricial or irregular emphysema
Deficiency of serum protein alpha 1 antitrypsin (alpha 1 antiprotease inhibitor) and the development of what form of emphysema is well established
Panlobular emphysema
Functional hallmarks of emphysema
Decreased airflow and diffusing capacity
Most important plain radiographic finding and reflects the loss of lung elastic recoil
Hyperinflation
In emphysema, loss of pulmonary capillary bed; associated chronic hypoxemia causes increased pulmonary vascular resistance manifests as
Enlarged central PAs; right heart enlargement (centrilobular)
In emphysema, presence of increased peripheral vascular markings (centrilobular) is due to
Small airways disease, increased pulmonary vascularity
treatment for emphysema
lung volume reduction surgery
this surgical procedure specifically benefits those with mostly upper lobe emphysema and low exercise capacity prior to surgery
lung volume reduction surgery
alterantive treatment for patients with emphysema, particularly younger patients with alpha 1 antitrypsin deficiency is
single or double lung transplantation
thin walled cystic spaces that exceed 1 cm in diameter and are found within the lung parenchyma
bullae
most often represent confluent areas of emphysematous lung and may be seen as part of generalized emphysema
bullae
rare cause of lung cysts or bullae is ____, which is an autosomal dominant disorder characterized by skin fibrofolliculomas, malignant renal tumors, and thin-walled lung cysts, the latter predisposing to spontaneous pneumothorax
Birt-Hogg-Dube syndrome
an accelerated form of paraseptal emphysema seen in young adult men; can also be associated with primary bullous disease
vanishing lung syndrome
non-cartilage bearing bronchioles with a luminal diamter of <2 mm
small airways disease
direct signs of small airway disease include
centrilobular nodules, centrilobular tree-in-bud opacities
indirect CT signs of small airways disease include
proximal bronchial dilatation, hyperlucent regions due to expiratory air trapping
pneumocystic jiroveci produce what opacities
geographic ground-glass opacification
refers to an inflammation of the small airways
bronchiolitis
infectious bronchiolitis in children are due to
RSV or adenovirus
form of bronchiolitis which reflecs a form of diffuse lymphoid hyperplasia of peribronchiolar lymphoid follicles of unclear clinical significance seen in patients with RA or sjogren syndrome
follicular bronchiolitis
aka bronchiolitis obliterans, is a subacute disease characterized pathologically by a mononuclear cell inflammatory process within the walls of respiratory bronchiles that leads to the formation of granulation tissue which plugs small airways
constrictive bronchiolitis
because postinfectious bronchiolitis obliterans affects the lungs asymmetrically and usually occyrs during a period of lung growth and development, the affected lung is typically small and hyperlucent and the ipsilateral PA is hypoplastic. These findings describe what syndrome
Swyer-James syndrome
rare form of constrictive bronchiolitis which is seen in middle-aged women who demonstrate severe airflow limitation and CT findings of air trapping with bronchial thickening and dilatation in association with one or multiple small nodules representing neuroendocrine cell tumorlets or inf the nodules are > 5 mm diameter, carcinoid tumors
diffuse idiopathic pulmonary neuroendocrine cell hyperplasia
