kongenitales lobäres Emphysem

Congenital lobar overinflation (CLO), previously called congenital lobar emphysema, is a congenital lung abnormality that results in progressive overinflation of one or more lobes of a neonate's lung.

On imaging, it classically presents on chest radiographs as a hyperlucent lung segment with overinflation and contralateral mediastinal shift.

Epidemiology

Congenital lobar overinflation is more common in males (M: F = 3:1).

Clinical presentation

Patients typically present with respiratory distress, most commonly in the neonatal period, and usually within the first six months of life .

Pathology

In congenital lobar overinflation, a lobe (or more) becomes distended and may or may not have an overabundance of alveoli. There are many presumed mechanisms for progressive overdistension of a lobe, including obstruction, cartilage deficiency, dysplasia, and immaturity . Most cases are idiopathic.

Associations

Congenital lobar overinflation may be associated with an aberrant left pulmonary artery and also with congenital heart defects:

• ventricular septal defect (VSD)
• patent ductus arteriosus (PDA)
• tetralogy of Fallot

Radiographic features

Interestingly, there is a pronounced predilection for certain lobes:

• left upper lobe: most common, 40-45%
• right middle lobe: 30%
• right upper lobe: 20%
• involving more than a single lobe: 5%
• much rarer in the lower lobes

Therefore, although the left upper lobe is most commonly affected, the right hemithorax is more commonly affected than the left .

Plain radiograph

Immediate postpartum period

The affected lobe tends to appear opaque and homogeneous because of fetal lung fluid or it may show a diffuse reticular pattern that represents distended lymphatic channels filled with fetal lung fluid.

Later findings

• appears as an area of hyperlucency in the lung with oligemia (i.e. paucity of vessels)
• mass effect with mediastinal shift and hemidiaphragmatic depression
• lateral decubitus film with the patient lying on the affected side will show little or no change in lung volume
• lateral film may show posterior displacement of the heart

CT

CT is usually performed to confirm the diagnosis, evaluate the mediastinal vascular structures, and to rule out other abnormalities.

• shows above features in greater detail
• attenuation of vascular structures in affected lobe
• may also show compressive atelectasis of adjacent lobes

Treatment and prognosis

Mildly symptomatic patients are usually followed up. Surgical resection or lobectomy is considered in severe cases .

Differential diagnosis

General imaging differential considerations include:

• bronchial atresia: the parenchyma distal to the atretic segment can have air trapping
• congenital pulmonary airway malformation (CPAM)
• pulmonary arterial hypoplasia
• pulmonary hypoplasia
• Swyer-James syndrome
• filamin A mutation

See also

• differential for unilateral transradiant hemithorax

Siehe auch:

• einseitige Transparenzminderung Thorax
• einseitig vermehrte Transparenz Thorax
• Aspiration
• Lungenhypoplasie
• Bronchialatresie
• congenital cystic adenomatoid malformation (CCAM) / congenital pulmonary airway malformation (CPAM)

und weiter:

• Lungenemphysem
• kongenitale pulmonale Atemwegsmalformation (CPAM)
• interstitielles Lungenemphysem
• Emphysemtypen
• PIE
• echogenic fetal lung lesions
• zystische Lungenläsionen bei Kindern
• cytic lung lesions - paediatric
• Emphysem
• kindliche Lungenläsionen
• Lungenfehlbildung
• Acute Respiratory Distress Syndrome neonatal