KEY FACTS Terminology • Vasa previa (VP): Umbilical (fetal) vessels under membranes < 2 cm from internal os Imaging • 90% associated with low-lying placenta • Can occur in 2…

KEY FACTS Terminology • Anomalous twin [twin reversed arterial perfusion (TRAP) twin] perfused by deoxygenated blood from pump twin • Blood enters fetus via umbilical artery (UA) ○ Reversed perfusion…

KEY FACTS Terminology • Extension of placental tissue beyond endometrial lining • Described as morbidly adherent placenta (MAP), placental adhesive disorder, and abnormally invasive placenta • Pathology subtypes of placenta…

KEY FACTS Terminology • Monosomy X is preferred term • Definition: Complete or partial deficiency of X chromosome Imaging • Cystic hygroma (CH) is hallmark finding ○ Large back of…

KEY FACTS Terminology • Synonym: Mermaid syndrome • Definition: Lower extremity fusion + other skeletal, gastrointestinal, and genitourinary abnormalities Imaging • Fused lower extremities (variable amount of fusion) ○ Severe…

KEY FACTS Imaging • Multiple causes; can be isolated or syndromic • Autosomal recessive polycystic kidney disease is single gene disorder ○ Large, diffusely hyperechoic kidneys most common ○ May…

KEY FACTS Terminology • Succenturiate lobe (SL): 1 or more accessory placental lobes connected by submembranous fetal vessels Imaging • 2 or more separate placentas ○ Color Doppler shows connecting…

KEY FACTS Terminology • Placenta detachment ○ Most often partial and can see hematoma • Categorized by location of abruption Imaging • Marginal abruption (most common) ○ Hemorrhage from edge…

KEY FACTS Terminology • Clubfoot (talipes equinovarus) ○ Foot is turned in at ankle (varus) ○ Foot is pointed (equina) • Rocker-bottom foot (congenital vertical talus) ○ Back of foot…

KEY FACTS Terminology • Fetal fusion of variable degree • Nomenclature ○ Site of fusion + suffix “pagus” – Omphalopagus : Abdomen fused from xiphoid to umbilicus, heart not involved…