Congenital Disorder of lung

congenital disorders of lung

1. 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

4. ◦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.

5. Development of lung

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

7. 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

8. 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”

9. 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

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

11. 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.

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

13. Mounier -Kuhn Syndrome

14. 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

15. ◦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.

16. 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

17. 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.

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

19. Development of lung

20. 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.

21. Elective surgical resection is treatment of choice for bronchogenic cyst.

22. Infected bronchogenic cyst

23. PARRENCHYMAL ABNORMALITIES AGENESIS AND HYPOPLASIA OF LUNG PULMONARY SEQUESTRATION

24. 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.

25. 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 .

26. Left Lung Hypoplasia

27. 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

28. 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

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

30. Radiological features

31. 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.

32. Thank You