congenital disorders of lung

1. Congenital Disorders of
Lung
Dr. Rikin Hasnani

2. • Development of lung
• Tracheobronchial abnormalities
• Parrenchymal abnormalities

3. Development
The respiratory system is an outgrowth of the ventral wall
of the foregut.
• The epithelium of the larynx, trachea, bronchi, and
alveoli originates in the endoderm.
• The cartilaginous, muscular, and connective tissue
components arise in the mesoderm.
• In the fourth week of development, the
tracheoesophageal septum separates the trachea from
the foregut, into the lung bud anteriorly and the
esophagus posteriorly.
• Contact between the two is maintained through the
larynx, which is formed by tissue of the fourth and
sixth pharyngeal arches

5. • ◦The lung bud develops into two main
bronchi: the right forms three secondary
bronchi and three lobes; the left forms two
secondary bronchi and two lobes.

6. Development of lung

7. TRACHEOBRONCHIAL ABNORMALITIES
• ◦TRACHEAL AGENESIS
• ◦TRACHEAL STENOSIS
• ◦TRACHEOMALACIA
• ◦TRACHEO-OESOPHAGEAL FISTULA
• ◦BRONCHIAL ATRESIA

8. Tracheal Agenesis
• Tracheal agenesis is a rare and in most cases lethal
anomaly. It may be suspected because of lack of
audible crying, and is often diagnosed right after birth
with water soluble contrast medium injected into the
oesophagus.
• Type 1: Absent upper trachea, & lower trachea
connecting to the oesophagus.
• Type2: Common bronchus connecting right and left
main bronchi to the oesophagus with absent trachea.
• Type 3: Right and left main bronchi arising
independently from the oesophagus

10. Tracheal Stenosis
• It is narrowing of Trachea.
• It is diffuse in 30% cases the parsmembranacea
being absent so that the trachea is encircled by
napkin ring cartilage.
• Segmental stenosis is more common and occurs
in equal frequency in upper middle and lower
trachea.
• In 20% of cases the stenosis is carrot or funnel
like and is associated with “Sling Left Artery
Syndrome”

12. Tracheomalacia
• Tracheomalacia is excessive weakness and collapsibility
of the tracheal wall as a result of abnormally soft or
pliable cartilage
• Primary: by congenital immaturity of the tracheal
cartilage.
• Secondary: previously normal cartilage undergoes
degeneration.
• Congenital (primary): Vascular ring, Tracheo-
Oesophageal Fistulas
• Acquired : prolonged Intubation , relapsing
polychondritis

13. • Patient presents in childhood with expiratory
airflow obstruction and apnoeic episodes.
• In severe cases aortopexy and various
trachealsplinting procedures may be
necessary.

15. Tracheobronchomegaly
• AKA Mounier-Kuhn Syndrome
• This is characterized by unusual width of the
trachea and main bronchi
• It is diagnose when diameter of trachea , right
main bronchus or left main bronchus size
greater than 3.0 cm; 2.4cm ; 2.3 cm
respectively.

16. • It is often complicated by recurrent LRTI and
Bronchiectasis due to ineffectiveness of
cough.
• Cough has loud booming quality.

17. Mounier-Kuhn Syndrome

18. Tracheo-oesophageal Fistula
•Type A: Corresponds to pure esophageal atresia without
fistula.
•Type B: is esophageal atresia with fistula between the
proximal pouch and the trachea.
•Type C: is esophageal atresia and fistula from the
trachea or the main bronchus to the distal esophageal
segment. (most common)
•Type D: is esophageal atresia with both proximal and
distal fistulas
•Type E: is tracheoesophageal fistula without atresia

20. • ◦In types A and B, there is complete absence of
gas in the stomach and intestinal tract;
• ◦In types C and D, the gastrointestinal tract
usually appears distended with air.
• ◦Three-dimensional CT and virtual bronchoscopy
allow accurate location of the site of fistula and
can show the length of gap between the proximal
and distal esophageal pouches.

21. Bronchial Atresia
• It probably arises as a result of a developmental
interruption of normal bronchial continuity in
which length of a bronchus becomes sealed off
from the larger proximal airways .
• Usually apicoposterior segmental bronchus of left
upper lobe is affected.
• The sealed off bronchus becomes distended by
bronchial secretions , resulting in the formation
of a cystic space or mucocele

22. • Majority of patients are asymptomatic and the
diagnosis of bronchial atresia is an accidental
finding.
• Chest radiograph shows the mucocele as a
coin lesion and part of the lung distal to it
appears hyperlucent as a result of collateral
air trapping.

24. Bronchogenic Cyst
• It arises as a result of abnormal budding of
tracheobronchial tree during the course of its
development between 26th day and 16th week
of intrauterine life therafter developing
seperately to produce a cystic structure.
• They may be central or peripheral.

25. Development of lung

26. • This patients are mostly asymptomatic
• When symptoms do occur, they result either
from mass affect on adjacent structure or due
to infection.
• X ray shows a well circumscribed , rounded,
homogenous opacity either in mediastenum
close to a major airway or in the lung
periphery, if a fistulous tract is present an air
fluid level may be seen.

27. • Elective surgical resection is treatment of
choice for bronchogenic cyst.

28. Infected bronchogenic cyst

29. PARRENCHYMAL ABNORMALITIES
• AGENESIS AND HYPOPLASIA OF LUNG
• PULMONARY SEQUESTRATION

30. AGENESIS AND HYPOPLASIA OF LUNG
• Agenesis means complete absence and
hypoplasia means underdevelopment of lung.
• Complete bilateral agenesis –incompatible with
life.
• Unilateral agensis is more common on left side.
• Cause is unknown, however condition that
decreases intrathorasic space, especially
congenital diaphragmatic hernia may cause
unilateral lung agenesis.

31. • Bilateral pulmonary hypoplasia is associated
with the presence of oligohydramnios caused
by renal tract anomalies or amniotic leak
syndrome.
• PROM and maternal use of ACE inhibitors are
other causes of pulmonary hypoplasia.

32. Left Lung Hypoplasia

33. Lung Sequesterations
• It is characterized by formation of an island of
abnormal unventilated lung tissue that has no
normal communication with the bronchial
system and derives its blood supply from
systemic , rather than pulmonary circulation.
• This are of two types
• 1) intralobar
• 2) extralobar

34. Feature Intralobar Extralobar
Frequency More common Less common
Male:female 1:1 4:1
Most commmon site Within Posterior basal
segment
Between lower lobe and
diaphragm
Side of thorax 60% left sided 90% left sided
Arterial supply 70% thorasic aorta 45% thorasiv aorta
Venous drainage Usually pulmonary vein Often systemic vein
Diagnosed in neonates Rarely Commonly
Other cong. defects Uncommon Frequent

35. Clinical features
• Extralobar are frequently diagnosed in 1st year
of life.
• Intralobar may present with LRTI, recurrent
pneumonic episode or massive hemoptysis.
• Extralobar sequestraaions are less liable to
infections

36. Radiological features

37. Treatment
• Symptomatic pulmonary sequestration should
be resected
• Any infection should be treated with
appropriate antibiotics.
• Intralobar sequestrations requires segmental
resection or lobectomy.
• Extralobar sequestrations may be resected
without disturbing normal lung.