Anal Atresia
KEY FACTS Imaging • Inability to demonstrate normal anal dimple or target sign • Normal appearance ○ Axial: Hyperechoic mucosa within hypoechoic muscular ring ○ Coronal: Hyperechoic mucosal stripe between…
ULTRASONOGRAPHY
Obstructive Renal Dysplasia
KEY FACTS Terminology • Definition: Genitourinary tract obstruction (at any level) causing renal parenchymal destruction Imaging • Progression: Urinary tract dilation (UTD) → ↑ renal echogenicity → small peripheral cortical…
Bilateral Renal Agenesis
KEY FACTS Terminology • Failure of kidneys to form Imaging • No kidneys in renal fossa or anywhere else in fetus • Adrenal glands are present and large, can mimic…
Choledochal Cyst
KEY FACTS Terminology • 5 types, but cystic dilation of common bile duct (CBD) is most common type seen in utero Imaging • Upper abdominal cyst associated with liver ○…
Multicystic Dysplastic Kidney
KEY FACTS Terminology • Multicystic dysplastic kidney (MCDK): Renal cystic dysplasia Imaging • Multiple noncommunicating cysts in kidney ○ Intervening renal tissue is sparse and abnormal ○ Large kidney size…
Genitourinary Tract
Embryology and Anatomy Kidney Formation • Kidney development undergoes a complicated series of formation and regression of primitive renal structures • Final kidney is formed from interaction of the ureteric…
Meconium Peritonitis, Pseudocyst
KEY FACTS Terminology • Chemical peritonitis due to intrauterine bowel perforation Imaging • Intraperitoneal calcifications in 85% ○ May be only finding if early perforation has healed • Implants on…
Duplicated Collecting System
KEY FACTS Terminology • Duplicated kidney with separate upper and lower pole collecting systems • Complete or partial duplication: Most in utero are complete Imaging • 2 separate ureters drain…
Duodenal Atresia
KEY FACTS Terminology • Lack of normal duodenal canalization leading to partial (web/stenosis) or complete obstruction (atresia) Imaging • Double bubble : Fluid-filled stomach and duodenum • Persistent fluid in…
Prune-Belly Syndrome
KEY FACTS Terminology • Disorder characterized by 3 principle components ○ Dramatic collecting system dilatation ○ Deficiency of abdominal musculature ○ Cryptorchidism (undescended testes) Imaging • Gross dilatation of bladder,…
