Ultrasound Anomalies Flashcards
What are some uses of prenatal US?
- viability
- GA
- multiple gestations (chorionicity, amnionicity)
- fetal anatomy and eval for abnormalities
- fetal growth
- identify high risk OB situations (placenta previa, dilated cervix)
- guide invasive procedures
- fetal echo
- dopplers evaluate blood flow
What is 2D US best for? 3D? 4D?
- 2D for internal structures
- 3D for surface
- 4D for movement
What the the benefits of US?
- noninvasive
- usually painless
- no ionizing radiation
- preferred image modality for dx and monitoring of pregnancy
- provides real-time imaging
- guide invasive procedures
- diagnose many severe anomalies and some minor anomalies
- good screening tool for chromosome conditions
- visualizes movement and live function in body
- allows for prenatal decision-making, prep, and planning
- possibly improve QOL for affected fetus
- no known risk
How often should US be used?
As Low As Reasonably Achievable (ALARA)
What are some limitations of US?
- AF needed for optimal visualization
- US waves don’t pass through air and need gel
- difficult penetrating bone
- maternal acoustics
- anxiety
- might provide undesired info
- cannot rule out all birth defects
- dx accuracy can be variable
- sometimes interp is subjective
What factors determine sensitivity of US?
- sonographer experience
- equipment
- GA
- maternal body habitus
- uterus position
- contents of uterus (fibroids)
- threshold for calling a marker
- a priori risk of abnormality
- RFR/low-risk pop vs. high-risk pop
- race/ethnicity
Define malformation
poor formation of tissue (cleft lip, CHD)
Define deformation
unusual forces on normal tissue (arthrogryposis)
Define disruption
breakdown of normal tissue (amniotic bands)
Define dysplasia
abnormal organization of cells in tissue
Define anomaly
marked deviation from normal, structural change, congenital defect
Define soft marker
abnormal findings that increase the chance of a chromosome abnormality but are not birth defects, commonly normal variations in development
True or False: soft markers have direct significance on the fetus itself
False
True or False: most markers are seen in fetuses w/o chromosome conditions
True
Give 5 examples of anomalies
- CHD
- duodenal atresia
- cystic hygroma
- spina bifida
- cleft lip/palate
