IMAGING OF CONGENITAL MALFORMATION OF THE LUNG

1. CONGENITAL
DISORDERS OF LUNG

2. INTRODUCTION
 Congenital lung abnormalities include a wide
spectrum of conditions and are an important cause of
morbidity and mortality in infants and children.
 Congenital lung abnormalities are being detected
more frequently at routine high-resolution prenatal
ultrasonography.
 Recognizing the antenatal and postnatal imaging
features of these abnormalities is necessary for
optimal prenatal counseling and appropriate peri- and
postnatal management.

3. EMBRYOLOGY
STAGE PERIOD EVENTS
Embryonal 3-5 wks Formation upto lobar bronchi.
Pseudoglandular 5-16 wks All bronchioles of conducting system
develop. Formation of columnar/cuboidal
epithelium.
Canalicular 16-24 wks Differentiation of epithelium, distal acinar
development.
Saccular 24-36 wks Alveoli and terminal sacs continue to
develop.
Alveolar >36 wks Maturation

4. Embryonal stage

5. Laryngeal/tracheal Pulmonary underde
Stenosis,TOF, Tracheomalacia
Pulmonary sequ. CCAM
Bronchogenic cyst. AV Malformation CLO
EMBRYONAL PSEUDO CANALICULAR SACCULAR ALVEOLAR
 GLANDULAR

 0 3 5 16 24 36

6. CLASSIFICATION
 The most commonly encountered anomalies can be
classified into three broad categories:
bronchopulmonary (lung bud)
anomalies
vascular anomalies combined lung and vascular
anomalies
lung agenesis-hypoplasia complex
(pulmonary underdevelopment),
congenital pulmonary
airway malformations (CPAMs),
CLO, bronchial
atresia, and bronchogenic cysts
absence of the main pulmonary
artery, anomalous origin of the left
pulmonary
artery or pulmonary sling,
anomalous pulmonary
venous drainage, and pulmonary
arteriovenous
malformations
scimitar syndrome and
bronchopulmonary sequestration
Vascular abnormalities may accompany bronchopulmonary abnormalities in some cases:
for example, pulmonary vascular abnormalities with pulmonary hypoplasia or agenesis, or
a systemic arterial supply to a small cyst CPAM (“hybrid” lesion)

7.  At imaging evaluation of any fetal chest mass, it is
important to note the presence of hydrops, the presence
or absence of a systemic arterial supply, mass effect on
the mediastinum, and other associated organ system
anomalies.

8. Normal Anatomy of the Fetal Thorax
 At US, the fetal lungs normally appear
homogeneous and are slightly more
echogenic than the liver.
 The echogenicity of the lung increases as
gestation advances.
 The presence of cysts or focal increased
echogenicity of the lung parenchyma
indicates a mass.
 On the four-chamber view, the heart occupies
25%–30% of the thoracic volume and is
positioned in the left anterior quadrant, just to
the left of the midline.
 The axis of the heart is determined relative to
the interventricular septum, which makes an
angle of 45° with the midline.
 Cardiomediastinal shift may often be the
first clue to the presence of a unilateral
chest mass or diaphragmatic hernia.

10. Normal Anatomy of the Fetal Thorax
 At MR imaging, the trachea, bronchi,
and lungs demonstrate high T2
signal intensity relative to the chest
wall muscles since they contain a
significant amount of fluid.
 As the lungs mature, there is
increasing production of alveolar
fluid, thereby increasing the signal
intensity of the lungs relative to the
liver

12. Pulmonary Underdevelopment
 Pulmonary underdevelopment has been classified
into three categories:

13.  More than 50% of affected fetuses have other abnormalities
involving the cardiovascular (patent ductus arteriosus, patent
foramen ovale), gastrointestinal (tracheoesophageal fistula,
imperforate anus), genitourinary, or skeletal (limb anomalies,
vertebral segmentation anomalies) system.

14. Pulmonary aplasia
 Imaging findings in pulmonary aplasia
and agenesis are similar, except for the
presence of a short blind ending
bronchus in aplasia.
 Postnatal radiography demonstrates
diffuse opacification of the involved
hemithorax with ipsilateral mediastinal
shift and computed tomography (CT)
helps confirm the absence of the lung
parenchyma, bronchus, and pulmonary
artery on the involved side.

16. Pulmonary hypoplasia
 A thoracic circumference below the 5th percentile for
gestational age indicates pulmonary hypoplasia.
 Other parameters indicating pulmonary hypoplasia are a
chest-trunk length ratio under 0.32 and a femur length–
abdominal circumference ratio under 0.16.
 Can be primary or secondary. Primary pulmonary hypoplasia,
in which a cause cannot be elucidated, is much less common
than secondary hypoplasia.
 The majority of cases of pulmonary hypoplasia are secondary
to a process limiting the thoracic space for lung development,
which can be either intrathoracic or extrathoracic.

18. INTRATHORACIS CAUSES EXTRATHORACIC CAUSES
COMMON: congenital diaphragmatic
hernia, which is left sided in 75%–90%
of cases, right sided in 10%, and
bilateral in 5%. Left-sided congenital
diaphragmatic hernia is relatively easier
to detect due to the presence of an
identifiable fluid-filled stomach in the
thorax
OTHER LESS COMMON: CPAM,
bronchopulmonary sequestration, a
cardiac or mediastinal mass, lymphatic
malformation, and agenesis of the
diaphragm.
COMMON: extrathoracic cause is
severe oligohydramnios, occurring
secondary to either (a) fetal
genitourinary anomalies such as renal
agenesis cystic renal dysplasia, and
urinary tract obstruction; or (b)
prolonged rupture of membranes.
OTHER LESS COMMON: skeletal
dysplasias, such as thanatophoric
dysplasia or Jeune syndrome, in which
a small and rigid thoracic cage causes
pulmonary hypoplasia

19.  In right-sided congenital diaphragmatic hernia, the liver
herniates into the chest, which may be difficult to detect
due to the solid echotexture of the liver. The herniated
liver can be confused with a mass originating in the lung
 Color Doppler imaging may be helpful in identifying the
portal and hepatic veins.
Pulmonary hypoplasia

20. Pulmonary hypoplasia

21. Pulmonary hypoplasia

22.  MR imaging provides greater soft-tissueontrast, which is
useful in assessing the size of the hernia and the location of
other abdominal viscera.
 MR imaging has been shown to be more sensitive than US in
detecting liver herniation.
 Meconium-filled large bowel is hyperintense on T1-weighted
images and hypointense on T2- weighted images; therefore,
intrathoracic herniation of the large bowel can easily be
detected at MR imaging
Pulmonary hypoplasia

28. Scimitar syndrome
• Unique form of lobar agenesis or aplasia
• Common feature hypoplasia or aplasia of
one or more lobes of the right lung.
• The hemithorax is small, with obscuration of
the heart border and a retrosternal soft-
tissue density
• Anomalous vein has the appearance of a
Turkish scimitar, which normally drains to
the IVC
• The right pulmonary artery may be absent
• Systemic vessel arising from the lower
thoracic or upper abdominal aorta supplying
the right lower lobe.

33. Pulmonary Sequestration
 Pulmonary sequestration is the second most common lung
lesion (after CPAM) detected antenatally.
 It is characterized by a portion of lung that does not connect
to the tracheobronchial tree and has a systemic arterial
supply, usually from the thoracic or abdominal aorta.
 Occasionally, the systemic arterial supply originates from the
celiac or splenic artery or from the intercostal, subclavian, or
even coronary arteries
Recurrent lower lobe pneumonia that does not clear with
antibiotic therapy may be the clue to the diagnosis

34.  Two types of sequestration have been described:
intralobar and extralobar.

35. CHARACTERSTIC INTRALOBAR EXTRALOBAR
Incidence More common ( 75 %) Less common( 25 %)
Gender predisposition Equal Men 4: 1
Laterality Left > right Left > right
Pleural investment Shares visceral pleura of parent lobe Separate visceral pleura
Bronchial Communication Yes No
Location
Posterior basal segments
(Approx. 60% on left)
Above, below or within diaphragm
(Approx. 90% on left)
Arterial supply Systemic Systemic; rare pulmonary
Venous Drainage Pulmonary venous Systemic venous (azygos, IVC, portal)
Associated anomalies Rare >50%
Presentation
Early adulthood with a history of
pulmonary infection, chronic cough,
or asthma.
Asymptomatic mass (15%)
Mostly present during first 6 months of life
due to respiratory or feeding problems
Radiographic Features
Homogeneous consolidation with
irregular margins or uniformly dense
mass with smooth or lobulated
contours.
Single well defined, homogeneous,
triangular shaped opacity in the lower
thorax. May present else where in the
thoracic cavity.

36.  Prenatal US, extralobar pulmonary sequestration is seen as a
homogeneous hyperechoic mass in a paraspinal location,
most often the left lower thorax.
 The feeding artery originating from the descending aorta may
be seen at color Doppler US.
 Prenatal MR imaging shows a solid, well-defined, uniformly
hyperintense mass on T2-weighted images, and the feeding
artery may be identified
 Postnatal CT depicts the feeding artery and may demonstrate
abnormal venous drainage.
 On postnatal radiographs, these lesions are seen as soft-
tissue masses with a smooth or lobulated contour, generally
in the lung bases
Pulmonary Sequestration

40.  CT of intralobar sequestration may show a homogeneous
soft-tissue mass, cysts containing air or fluid, focal
emphysema, or a hypervascular focus of lung parenchyma.
Pulmonary Sequestration

43. CASES

44. Newborn with respiratory distress.
White left lung with diffuse interstitial opacity and
hyperexpansion of the right lung. The trachea is deviated
to the left, as is the cardiac silhouette, suggesting collapse
of the left lung with mediastinal shift toward it.
CT chest with contrast axial images lung and mediastinal
window confirms left lung agenesis with ipsilateral
deviation of the heart and hyperinflation of the right lung.
There is a subtle left bronchial remnant. Absence of the
left pulmonary artery. Moreover, between the X-ray and
this examination, the patient had a sternotomy for
correction of TAPVR. However, in this examination, the
pulmonary veins still drain into the right atrium.

45. CT with intravenous contrast shows complete collapse of
the superior segment of the right lower lobe. A
prominent artery arises from thoracic aorta at the level of
T7 supplying this segment and it is drained by a large vein
into the right pulmonary vein.
Chest X-ray frontal projection show an ill-defined opacity
in the right lower zone, adjacent to the right cardiac
border, without silhouetting it, suggesting to be locate in
the left lower lobe.
20 month old boy with persisting abnormality on CXR.

46. 2 months old boy with cyanosis of extremities.

47. Chest Scanogram show right sided large homogenous opacity associated with decrease lung volume of
right side with contralateral mediastinal shifting.
In coronal images CT with contrast of chest show a soft tissue mass in base of right lung that is supported
by single artery arising form abdominal aorta.
Another finding is also seen the right pulmonary vein in drained to portal circulation
3D reconstruction confirm the systemic supply of the sequestration and aberrant communication of
Schimoler
Another anomalies was also seen including left sided SVC, ASD, and aberrant RSCA
Scimitar syndrome with extra-lobar sequestration

48. s