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Case No. 03 - Answer


Congenital high airway obstruction syndrome (CHAOS) with hydrops fetalis

  • Rare abnormality with poor prognosis in which upper airway is congenitally obstructed  with most common cause is laryngeal atresia.

  • Due to obstruction, entrapment of fluid occurs in trachea and lungs leading to hyperinflation of lung and flattening of domes of diaphragm.

  • Heart gets compressed leading to elevated intrathoracic pressure and ascites, placentomegaly and hydrops fetalis.

  • Causes:  Intrinsic: Laryngeal atresia, laryngeal web, tracheal atresia, subglottic stenosis, tracheal agenesis, laryngeal web, tracheal web


      Extrinsic: Cystic hygroma and teratoma ( neck mass causing compression)


Clues to diagnosis

  • Enlarged echogenic lungs on USG

  • Very bright T2W signal of the lungs on MRI

  • Diaphragmatic flattening and inversion ( small arrows)

  • Dilated anechoic fluid filled trachea ( block arrow)( hyperintense on MRI)

  • Cause of obstruction may be detected ( subglottic stenosis in index patient)



      EXIT procedure ( Ex-utero intrapartum procedure)

  • Perinatal operation on placental support in which only the head of the fetus is delivered followed by laryngoscopic  examination and tracheostomy

Correct Answer Submitted by:

  1. R Praveen Kesav

  2. Nikhil Gupta

  3. Arjunlokesh

  4. Richa Yadav

  5. Pranav K Santhalia

  6. Soumya Ranjan Malla

  7. Neha Mohan

  8. Prabhat Bhagat

  9. Atula Jain

  10. Neha Dohare

  11. Apurva Surana

  12. Anuradha Dawani

  13. Preetham Patavardhan

  14. Taruna Yadav

  15. Mayoukh Sarkar

  16. Narasimman Murugan

  17. Anupama Ramachandran

  18. Dipin Sudhakaran

  19. Ankit Sangwan