Normal Thorax
What structures are evaluated in the fetal thorax?
Lungs, Heart, and diaphragm
What is pulmonary hypoplasia?
Reduction in lung volume resulting in small, inadequately developed lungs.
Which abdominal wall defect is covered by a membrane?
Omphalocele
What is the “double bubble” sign diagnostic for?
Duodenal atresia
If the stomach is not visualized at the start of a scan, what should the sonographer do?
Reassess later during the exam before assuming abnormality
How does fetal lung echogenicity change as gestation progresses?
Eary gestation = less echogenic than liver
Late gestation = similar echogenicity to liver
Another name for pleural effusion is?
Hydrothorax
Which defect is usually located to the right of the umbilical cord insertion and lacks a covering?
Gastroschisis
Which condition results from abnormal deviation of the tracheoesophageal septum?
Esophageal atresia
What extra feature should be evaluated when diaphragmatic hernia is suspected?
Cardiac orientation and stomach location
What is the normal chest to abdominal circumference ratio?
What vascular feature helps identify bronchopulmonary sequestration?
A feeder artery arising from the descending thoracic aorta
Omphalocele is often associated with which chromosomal anomalies?
Trisomy 13 & 18.
Which condition is linked to megacolon due to missing nerve innervation?
Hirschsprung’s disease
How does the echogenicity of the small bowel compare to the colon?
Small bowel is more echogenic than colon
Thoracic mass (CPAM, BPS) or diaphragmatic hernia
Which type of CCAM has the best prognosis?
Type I (dominant cyst)
A sonographer identifies abdominal contents herniating through the diaphragm with the stomach in normal position. Which specific defect should be suspected?
Morgagni hernia (anterior/medial defect)
Polyhydramnios is seen with duodenal atresia. Explain the physiologic reason why
Amniotic fluid cannot pass beyond the obstruction in the duodenum, preventing normal swallowing/absorption, leading to fluid accumulation
A fetus presents with bowel loops floating freely in amniotic fluid, polyhydramnios, and elevated maternal serum AFP. What is your diagnosis?
Gastroschisis; bowel is free-floating with no covering membrane, usually right of the umbilical cord insertion.
A normal chest/ abdominal circumference ratio is 0.94:1. If the ratio is significantly below this, what pathology is most suspected?
Pulmonary hypoplasia
Sonographically, how can extralobar bronchopulmonary sequestration be differentiated from intralobar sequestration?
Extralobar has its own pleural sac and is strongly associated with hydrops; intralobar lies within the normal pleural sac
A fetus presents with omphalocele, ectopia cordis, and an anterior diaphragmatic defect. What syndrome is this, and what additional associated anomalies are expected?
Pentalogy of Cantrell; also includes lower sternum defect and diaphragmatic pericardium defect (often limb-reduction anomalies too)
A fetus has echogenic bowel, polyhydramnios, and absent stomach bubble. Which anomaly should be suspected, and how might a tracheoesophageal fistula alter the findings?
Esophageal atresia; a distal TE fistula may allow some fluid to reach the stomach, so the stomach may appear intermittently filled
A fetus presents with an abdominal wall defect, polyhydramnios, and suspected cardiac anomaly. The defect appears covered by a membrane. What diagnosis is most likely, and what additional sonographic evaluations should be performed?
Omphalocele; evaluate for associated anomalies (especially cardiac defects, Trisomy 13 & 18, and syndromes such as Beckwith-Wiedemann)