This document discusses congenital disorders of the lung across different embryological stages. It covers formation of the conducting airways from 3-16 weeks and alveolar development from 16-36 weeks. Specific disorders are then discussed in more detail, including tracheal atresia, tracheomalacia, bronchogenic cyst, congenital lobar emphysema, and pulmonary sequestration. Imaging and clinical features of each condition are provided.

1. CONGENITAL
DISORDERS OF
LUNG

2. 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

3. Embryonal stage

4. 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

5. TRACHEAL ATRESIA
• Very rare, associated with maternal polyhydramnious.
• C/F : Immediate and acute with severe distress, absence of cry, inability to
intubate.
• Types:

6. Tracheal stenosis
• Rare, usually acquired is more common.
• Complete tracheal cartilage rings.
• Focal ( 50 % ) usually lower third , genaralised ( 30 % ) ,
funnel shaped ( 20 % ).
• Clinical features: Variable
• Search for other anomalies of lung.
• IMAGING: Radiographs: High voltage.
CT : Dynamic changes in airway.
MRI: Relationship with Vessels

7. images

8. Tracheomalacia
• Malacia= Softening.
• Softening due to abnormality of cartilage and myoelastic elements.
• Associated with relapsing polychondritis, chondromalacia, MPS like hurlers and
hunter syndromes, Mounier-kuhn syndrome, TOF, vascular ring.
• Clinical features: Similar to asthma like wheeze, cough, dyspnea. Expiratory
wheeze increasing with cry and disappears on rest.

9. • Imaging:
Fluoroscopy
Dynamic CT
Bronchoscopy

10. Tracheal Bronchus
• First described by Sandifort in 1785 as a right upper bronchus originating
from trachea.
• Variety of bronchial anomalies arising from trachea or main bronchus
directed towards upper lobe territory.
• Two types : Displaced
Supernumerary : Tracheal diverticula.
Apical accessory lungs or tracheal lobes.
• When the entire upper lobe bronchus is displaced on trachea, it is also
called as “pig bronchus”.
• Clinical features: Asymptomatic, persistent upper lobar pneumonia,
atelectasis or air trapping.

12. TRACHEO-OESOPHAGEAL FISTULA
• Associated with oesophageal atresia.
• Polyhydramnious prenatally, postnatally the diagnosis is usually
made in the neonate, as they experience feeding difficulties and
respiratory compromise due to repeated aspiration and failure to
pass nasogastric tube.
• Around 50 % are associated with congenital anomalies: CVS
anomallies, VATER/VACTERL, chromosomal anomalies, GI
anomalies.

13. TRACHEO ESOPHAGEL FISTULA

14. Bronchial atresia
• Focal obliteration of a proximal segmental or subsegmental bronchus that
lacks communication with the central airways. The development of distal
structures is normal.
• The alveoli supplied by these bronchi are ventilated by collateral pathways
through intraalveolar pores of the Kohn, bronchoalveolar channels of
Lambert, interbronchiolar channels and show features of air-trapping,
resulting in a region of hyperinflation around the dilated bronchi.
• Usually asymptomatic. May simulate a mass/ solitary pulmonary nodule or less
frequently as congenital lobar emphysema.
• Chest Radiograph: Bronchocele, seen as rounded, branching opacities
radiating from the hilum. The distal lung is emphysematous and produces an
area of hyperlucency around the affected bronchi. In newborns, the affected
segment may be seen as a fluid-filled mass.
• CT is an excellent modality for excluding the presence of a hilar mass and
precisely determining delineation and location of lesions. In doubtful cases,
multiplanar reformation helps distinguish mucoid impaction from nodular
lesions.

16. BRONCHOPULMONARY FOREGUT
MALFORMATIONS
1. Foregut abnormalities
Bronchogenic cyst
Esophageal/Neuroentericcyst
Tracheoesophageal fistula
2. Airway abnormalities
Tracheal Atresia
Bronchial Atresia
Tracheal Bronchus
3. Parenchymal abnormalities
Pulmonary Agenesis/Hypoplasia
CLE
Pulmonary sequestration
CPAM

17. Bronchogenic cyst
• Represent around 50 % of the foregut malformations and are the most
common primary cysts of the mediastinum.
• Bronchogenic cysts occur along the differentiating pathway of the trachea
and bronchial tree, and are thought to represent abnormal budding of
foregut tissue.
• They are lined by columnar ciliated epithelium, and their walls often
contain cartilage and bronchial mucous glands. It is unusual for them to
have a patent connection with the airway, but when present, such a
communication may promote infection.
• Location: 1. Mediastinal : Most common.
Site: Para tracheal, carinal (M.C) , hilar.
2. Intrapulmonary: Medial third of the lung.
3. Lower neck ( V.Rare).

18. • Two-thirds of the patients are symptomatic; symptoms are due to the size
and position of the cyst. Symptoms are most frequently caused by
compression of the trachea or bronchi. However, most bronchogenic
cysts in children are found incidentally when imaging is performed for
other reasons.
• In infants and children, the chest radiograph is diagnostic for
bronchogenic cysts in three out of four cases. The cysts are filled with
serous or mucous fluid, so usually appear as water-density mass lesions in
chest radiographs.
• CT: Locating an intrathoracic cyst, defining its extent, relation to key
structures, and characterizing the intrinsic density. The cysts show no
contrast enhancement, but when they become infected they may show
wall enhancement.
• MRI: T1- Variable, T2- hyper intense.

20. Congenital cystic adenomatoid malformation
• Also called as congenital pulmonary airway malformation.
• Hamartomatous proliferation of the terminal bronchioles at the expense
of alveolar development between the 7th and 10th weeks of embryonic
life, contain both cystic and solid tissue.
• Three types:
• TYPE 1: Most commmon ( 50 %)
Cysts of variable sizes with one dominant cyst( > 2 cm).
5 % aasocited with congenital anomalies.
Excellent prognosis.
TYPE 2: 41%
Small uniform cysts ( 1cm)
50 % associated with congenital anomalies.

21. • TYPE 3: Least common type.
Micro cysts and appears solid.
Usually involves one lobe.
Poor prognosis.

23. PULMONARY SEQUESTRATION
• Pulmonary sequestration is defined as an aberrant lung tissue mass
that has no normal connection with the bronchial tree or with the
pulmonary arteries.
• The arterial blood supply arises from the systemic arteries, usually
the thoracic or abdominal aorta.

24. CHARACTERSTIC INTRALOBAR EXTRALOBAR
Incidence More common ( 75 %) Less common( 25 %)
Gender predisposition Equal Men 4: 1
Pleural investment Shares visceral pleura of
parent lobe
Separate visceral pleura
Location Posterior basal segments
(Approx. 60% on left)
Above, below or within
diaphragm
(Approx. 90% on left)
Venous Drainage Pulmonary venous Systemic venous (azygos,
IVC, portal)
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.

27. SCIMITAR SYNDROME
• Scimitar syndrome (SYN: pulmonary venolobar syndrome or hypogenetic
lung syndrome)is characterised by a hypoplastic lung that is drained by an
anomalous vein into the systemic venous system.
• It is essentially a combination of pulmonary hypoplasia and PAPVR. It
almost exclusively occurs on the right side.
• Haemodynamically, there is an acyanotic left to right shunt. The
anomalous vein usually drains into IVC- M.C, right atrium, portal vein.
• The lung is frequently perfused by the aorta, but the bronchial tree is still
connected and thus the lung is not sequestered.
• Associated anomalies: CHD, diaphragmatic anomalies, vertebral
anomalies, GU anomalies.
• Three forms are described: Infantile, adult form, associated with
anomalies.

30. PULMONARY UNDERDEVELOPMENT
• 3 GROUPS : AGENESIS: Absent bronchi, lung.
APLASIA: Rudimentary bronchus without lung tissue.
HYPOPLASIA: Reduction in lung tissue.
• The abnormality is usually unilateral, and there is no side or gender
predominance). More than 50% of children with pulmonary agenesis
have associated congenital anomalies.
• HYPOPLASIA: It is characterized by the presence of both bronchi and
alveoli in an underdeveloped lobe, and it is caused by factors directly or
indirectly compromising the thoracic space available for lung growth,
such as a congenital diaphragmatic hernia, extralobar sequestration,
agenesis of the diaphragm, large pleural effusion, and Jeune syndrome
(asphyxiating thoracic dystrophy), a rare entity in which a small and rigid
thoracic cage produces a decrease in lung volume.
• The extrathoracic causes include oligohydramnios (Potter syndrome) .
Other causes include decreased pulmonary vascular perfusion (tetralogy
of Fallot, unilateral absence of the pulmonary artery).

32. CONGENITAL LOBAR OVERINFLATION
( ? EMPHYSEMA)
• Characterized by progressive overdistention of a lobe, sometimes
two lobes. It is thought to result from a ball-valve mechanism at the
bronchial level.
• The most commonly affected lobe is the left upper lobe, followed
by the middle lobe.
• In around 50 % of patients areas of malacia or stenosis of the
bronchial cartilage were found and these are considered the most
likely explanations.
• Myers described three clinical types. Infancy (type I), in older
children (type II), or is an incidental finding in asymptomatic
patients (type III). Types II and III are rare.
• Respiratory distress is the most common symptom at presentation.