CHEST Flashcards
CHEST
A 46-year-old American man who has come to the UK on a holiday trip arrives at the AED with worsening shortness of breath. Chest X-ray shows bilateral asymmetrical calcified mediastinal and hilar nodes, and chronic pulmonary histoplasmosis is provisionally diagnosed. The worsening symptoms are attributed to fibrosing mediastinitis. All the following conditions can occur as complications of fibrosing mediastinitis, except
A. SVC syndrome
B. Pulmonary arterial hypertension
C. Pulmonary venous stenosis
D. Tracheal stenosis
E. Aortic stenosis
51. A 70-year-old pensioner
E. Aortic stenosis
Chronic histoplasmosis may lead to two well-described complications: fibrosing mediastinitis and broncholithiasis. Fibrosing mediastinitis is a fibrotic immune response to histoplasma antigens. The abnormal fibrosing process encases and narrows vital mediastinal structures, which can lead to superior vena cava syndrome, precapillary pulmonary arterial hypertension from pulmonary arterial stenosis, post-capillary pulmonary arterial hypertension owing to pulmonary vein stenosis, atelectasis from bronchial obstruction, tracheal stenosis, or dysphagia from oesophageal obstruction. The imaging appearance can mimic infiltrating metastatic disease or lymphoma; however, the presence of mediastinal calcifications often provides a clue to the diagnosis. Broncholithiasis results from erosion of a calcified hilar lymph node into an adjacent bronchus. Affected patients present with chronic cough and haemoptysis and even occasionally with lithoptysis. Typical imaging features include endobronchial calcification with atelectasis of the associated pulmonary segment or lobe.
CHEST
In order of frequency, the most common location of congenital lobar emphysema is as follows:
A. LUL, LLL, RUL
B. LUL, RML, RUL
C. RUL, RML, LLL
D. LUL, RUL, RLL
E. LUL, RML, RLL
(LLL - left lower lobe, LUL left upper lobe, RLL right lower lobe, RML right middle lobe, RUL - right upper lobe)
B. LUL, RML, RUL
Congenital lobar emphysema represents a condition of progressive over-distension of one or multiple pulmonary lobes secondary to deficiency/immaturity of bronchial cartilage, endobronchial obstruction, or extrinsic compression. It is more common in boys.
Preferential involvement is LUL (left upper lobe) > RML (right middle lobe) > RUL (right upper lobe) > two lobes.
Initial chest X ray shows opacification of lobe secondary to delayed clearing of pulmonary fluid; this is followed by progressive features of air trapping, hypertranslucent lung and mediastinal shift.
CHEST
Which of the following is false regarding bronchopulmonary sequestration?
** Intralobar -- Extralobar**
A. Pleural involvement: Visceral pleura – Own pleura
B. Venous drainage: Pulmonary veins – Systemic veins
C. Associated anomalies: Less common – More common
D. Symptomatic: First 6 months – Adulthood
E. Arterial supply: Aorta – Aorta
**D. Symptomatic First 6 months Adulthood **
Bronchopulmonary sequestration
Intralobar - - - - Extralobar
Prevalence: 75% - - - - 25%
Pleural involvement: Visceral pleura - - - - Own pleura
Venous drainage: Pulmonary veins - - - - Systemic veins
Associated anomalies: Less common (15%) - - - - More common (50%)
Symptomatic: Adulthood - - - - First 6 months
Arterial supply: Thoracic aorta - - - -Thoracic aorta
Aetiology: Acquired - - - - Developmental
CHEST
The following are diagnosed prenatally on ultrasound examination or MRI, except
A. Pulmonary interstitial emphysema
B. Bronchial atresia
C. Pulmonary sequestration
D. Congenital pulmonary airway obstruction
E. Congenital diaphragmatic hernia
A. Pulmonary’ interstitial emphysema
MRFs excellent tissue contrast resolution allows easy differentiation between organs, allowing prenatal diagnosis of congenital diaphragmatic hernia. MRI is also useful in the evaluation of foetal lung maturation through volume and signal intensity.
Congenital cystic adenomatoid malformation (CCAM) is the most commonly diagnosed lung malformation. In CCAM, abnormal branching of the immature bronchioles and lack of normal alveolar development results in a solid/cystic intrapulmonary mass.
Most pulmonary sequestrations detected prenatally are extralobar, with an anomalous vein that drains into the systemic circulation. On T2-weighted images, they are seen as well-defined hyperintense masses with or without hypointense septa. Intralobar sequestration may be difficult to differentiate from CCAM.
MRI is also useful for evaluating other pulmonary and thoracic anomalies. Bronchogenic cysts are identified as hyperintense lesions on T2-wcightcd sequences; they are usually single lesions, located in the lung or mediastinum. Oesophageal duplication cysts are also identified as hyperintense mediastinal lesions. Congenital lobar emphysema can be difficult to distinguish from intralobar sequestration and from CCAM.
Pulmonary interstitial emphysema refers to the abnormal location of air within the pulmonary interstitium, resulting from rupture of over-distended alveoli following barotrauma in infants who have surfactant deficiency lung disease.
