Learning objectives
The respiratory system develops from the ventral wall of the foregut endoderm and mesoderm during 3th and 4th gestation weeks and continues its development during intrauterus life.
Defects in any step of this embryological formation results in congenital anomalies,
such as: bronchial atresia,
tracheal agenesis,
tracheoesophageal fistula,
anomalous bronchi,
congenital high airway obstruction sequence (CHAOS) and tracheal membrane
This education exhibit aims to:
1. Discuss and illustrate the embryology and congenital anomalies related to the respiratory diverticulum,
including rare and fatal cases.
2. Review iatrogenic...
Background
The respiratory diverticulum (lung bud) appears as an outgrowth from the ventral wall of the foregut when the embryo has approximately 4 weeks.
Respiratory diverticulum is of endodermal origin,
and it forms the epithelium lining of the larynx,
trachea,
and bronchi,
as well as that of the lungs.
The cartilaginous,
muscular,
and connective tissue components of the trachea and lungs are derived from the splanchnic mesoderm surrounding the foregut.
Initially,
the lung bud is in open communication with the foregut.
When the diverticulum expands caudally,...
Findings and procedure details
Case 1
Newborn preterm (35 weeks and 1 day) with severe respiratory distress,
cyanosis and absence of audible crying at birth.
Attempt to perform intubation and tracheostomy without success.
Emergential bronchoscopy was performed and a membrane blocking the opening in the trachea was found.
FIGURES 1 to 5
Case 2
Patient with fever,
cough and vomiting for two days.
Chest radiograph were performed incidentally showing a tracheal bronchus.
FIGURE 6
Case 3
Pregnant woman diagnosed with pre-eclampsia following high-risk pregnancy due to fetal malformation.
FIGURES...
Conclusion
Respiratory diverticulum passes through many steps during its embryological formation.
Defects in each step can result in congenital anomalies,
such as bronchial atresia,
tracheal agenesis,
tracheoesophageal fistula,
anomalous bronchi,
congenital high airway obstruction sequence (CHAOS) and tracheal membrane.
Although imaging findings are typical,
radiologists must improve skills in detecting this pathologies helping multidisciplinary team in planning management and best prognosis.
References
Mong A,
Johnson AM,
Kramer SS,
Coleman BG,
Hedrick HL,
Kreiger P,
et al.
Congenital high airway obstruction syndrome: MR/US findings,
effect on management,
and outcome
Sanford E,
Saadai P,
Lee H,
Slavotinek A.
Congenital high airway obstruction sequence (CHAOS): a new case and a review of phenotypic features.Am J Med Genet A.2012;158A:3126–36
Heidinger BH,
Occhipinti M,
Eisenberg RL,
Bankier AA.
(2015).Imaging of Large Airways Disorders.AJR Am J Roentgenol,205: 41-56
Charline Bertholdt,
Estelle Perdriolle-Galet,
Pascale Bach-Segura,
and Olivier Morel,
“Tracheal Agenesis: A Challenging Prenatal Diagnosis—Contribution...