Anhydramnios
Anhydramnios is a term where there is a complete or near-complete lack of amniotic fluid (sometimes referred to as "liquor volume").
On this page:
Pathology
Anhydramnios can result in a number of situations:
- fetal renal tract anomalies
- Potter syndrome (bilateral renal agenesis): most common
- large ureterocoele: if capable of causing bilateral renal tract obstruction 6
- posterior urethral valves: with severe/complete obstruction 1
- preterm premature rupture of membranes (PPROM)
- placental insufficiency 4
- silent uterine rupture 4
- nimesulide therapy (single report only 5)
- chemotherapeutic agents administered during pregnancy
- trastuzumab/paclitaxel 3
Radiographic features
Antenatal ultrasound
Typically shows a complete absence of amniotic fluid around the fetus. Color Doppler interrogation may be of value in selected cases when loops of cord around the fetus mimic amniotic fluid 2. However demonstration of vascularity within the same can help differentiate the loops from amniotic fluid. Visualization of fetal structures can sometimes be very difficult due to the absence of amniotic fluid.
Complications
- fetal akinesia deformation sequence with the development of pulmonary hypoplasia if anhydramnios has been present for a long period
See also
Related Radiopaedia articles
Ultrasound - obstetric
- ultrasound (introduction)
- obstetric ultrasound
- first trimester and early pregnancy
- ectopic pregnancy
- multiple gestations
- subchorionic hematoma
- failed early pregnancy
-
second trimester
- fetal biometry
- fetal morphology assessment
- fetal echocardiography views
- non-visualization of the fetal stomach
-
soft markers
- nuchal fold thickness
- ventriculomegaly
- absent nasal bone
- choroid plexus cysts
- enlarged cisterna magna
- shortened fetal long bones
- echogenic intracardiac focus (EIF)
- echogenic fetal bowel
- aberrant right subclavian artery
- fetal pyelectasis / fetal renal pelvic dilatation
- single umbilical artery
- sandal gap toes
- amnioreduction
- Doppler ultrasound
- nuchal translucency
- 11-13 weeks antenatal scan
- chorionic villus sampling (CVS) and amniocentesis
- placenta
- other