The identification of echogenic or dilated bowel on fetal ultrasonography may be an early indication of cystic fibrosis (CF) or trisomy.
Slotnick and Abuhamad developed a classification for bowel echogenicity based on how the bowel image changed with gain reduction as compared to bone in the iliac crest.
Disappearance After Gain Reduction |
Ultrasonographic Findings |
Grade |
no increase in sonodensity |
normal fetal bowel |
0 |
sonodense, with image lost before bone in the iliac crest |
slight hyperechogenicity |
1 |
sonodense, similar to bone in the iliac crest |
moderate hyperechogenicity |
2 |
sonodense with image lost after bone in iliac crest |
marked hyperechogenicity |
3 |
Grade |
Risk of CF or Trisomy |
0 |
very low |
1 |
very low |
2 |
low |
3 |
low to moderate (5 to 45%) |
The dilation of small bowel loops may indicate bowel obstruction due to a meconium plug or other cause.
The workup of hyperechogenic and/or dilated small bowel loops may include:
(1) a careful ultrasonographic examination for other abnormalities
(2) consider performing cytogenetics and testing for cystic fibrosis on the fetus
(3) consider testing the parents for cystic fibrosis
Specialty: Obstetrics & Gynecology, Pedatrics
ICD-10: ,