·         Intra-abdominal calcifications-Scattered foci of increased echogenicity in the distribution of the liver, spleen and peritoneal cavity, with or without acoustic shadowing, usually secondary to in utero perforation.

 

·         Meconium peritonitis- This is the most common cause of abdominal calcification; it may be associated with dilated loops of bowel and PH. Cystic fibrosis should be considered.

 

·         Meconium psudocyst- A cystic mass with hyperechoic margins secondary to perforation.

 

 

·         Transplacental infections-Toxoplasmosis, CMV, varicella cause liver calcification.

 

·         Portal vein thrombosis- Portal vein thrombosis may show calcification in the portal vein distribution but portal vein thromboemboli may resemble other causes of hepatic calcifications, i.e. infections.

 

·         Atretic bowel segment- Intramural calcification may occur in an atretic bowel segment.

 

·         Neoplasia-Many abdominal neoplasms, including neuroblastoma, teratoma, hemangioma and hepatoblastoma, are known to calcify in neonates.

 

 

·         Calcified IVC and renal vein thrombus- Uncommon. Combined thrombosis of IVC and renal vein is an uncommon occurrence in the neonate and is extremely rare in utero. Hyperechoic streaks in the distribution of the IVC and renal vein are noted and may shadow. Venous collaterals may be demonstrated by Doppler.

 

·         Urinary ascities-A rare cause of peritoneal calcification in the neonate following bladder or pelvicalyceal rupture secondary to obstruction.

 

 

·         Tissue necrosis- Tissue necrosis is a well known cause of calcification. Ischemic hepatic necrosis as a cause of fetal hepatic calcification has been reported.

 

·         Hyperdense intramural material-Dense structures such as inspissated meconium/meconium ileus and hematomas often cause increased fetal abdominal echogenicity, usually in obstructed bowel.

 

·         Multiple interface- Rhabdomyosarcomas are exceedingly rare tumors that may occur in a neonate. They have multiple reflective interfaces.

 

 

·         Air within the fetus- This is usually secondary to fetal demise. An echo pattern consistent with gas in the large bowel of a live fetus has been reported, presumably secondary to amnionitis.

 

·         Fat-Lipomas, if detected prenatally, may conceivably cause increased

echogenicity.