all about ultrasound and pregnancy and placentae Basic to intermediate level

1. Placentae
Chris Griffin
Consultant Maternal Fetal Medicine
King Edward Memorial Hospital
Perth
Western Australia

2. Development of placenta
• Process of cellular changes
– Cellular Division
– Cellular hypertrophy
– Cellular apoptosis
• Implantation
– Upper part of post wall of
uterine body near midsagital
plan

3. Early Ultrasound Findings
• 5 to 12 weeks Online essay
Vitelline duct at 6weeks+
Yolk sac at 5 weeks
Retro amniotic 11 weeks

4. Placental Lakes

5. Lakes

6. Hydatidiform mole

7. Placenta Praevia
• Risk factors
– Previous CS
• 5% only fundal cf 15% no
CS
• Lower implantaion site
• Multiple pregnancy
• IVF
• Smoking
• Placenta Praevia
– Second trimester TA
• 20% incidence of low lying
• 1 to 2% major incidence
• 50% resolve
– First Trimester TVS
• 6% incidence
• 1% incidence at 15 – 20
weeks
• If placenta overlying
internal os by 1 cm then
100% sensitivity for PP with
85% specificity

8. TVS for placenta praevia

9. Morbidly Adherent Placenta
• Loss of echolucent area between bladder and
uterus
• Bladder line: thinning or interruption of
hyperechoic interface between uterine serosa
and bladder wall
• Placental Lacuna with turbulent high velocity
flow

10. Loss of echolucent area

12. Succenturiate Lobe

13. Two placental masses

14. Use colour flow

15. Succenturiate lobe Vasa Praevia

16. Velamentous cord insertion

17. Mangrove Sign

18. Placenta membranacea
(placenta diffusa):
 all the membranes are covered by functioning villi & placental tissue
forms on all pheripheral chorion. Sonographically the placenta
appears to cover most or the entire uterine wall. Often associated
with placental anomalies such as; accreta, increta, percreta & vasa
previa.

19. Vasa Praevia:
• Complication in which fetal blood vessels cross over or come in
close proximity to the internal os. Associated with velementous cord
insertion or placental morphological anomalies ie. Succinuate or
bilobate
??Failure of rotation of the embryonic pole to the endometrium

20. Placenta teddy bear
• London-based designer Alex Green (2008)
The placenta must first be cured with salt to kill bacteria and remove
water. Green then softens the dried organ with a mixture of eggs and
tannins.
Once he cuts and sews the bears, Green fills them with brown rice.
Most end up to be 5 inches tall.

21. Other placental concerns
?
? ?

22. ?

23. ?

24. Chorionicity

25. Placenta Grannum
Grade 0
Uniform moderate
echogenicity
Smooth chorionic
plate without
indentations

26. 1
• Grade 1
• Mid 2nd trimester –early
3rd trimester (~18-29
wks)
• Subtle indentations of
chorionic plate
• Small, diffuse
calcifications
(hyperechoic) randomly
dispersed in placenta

27. 2
• Grade 2
• Late 3rd trimester (~30
wks to delivery)
• Larger indentations
along chorionic plate
• Larger calcifications in a
“dot-dash”
configuration along the
basilar plate

28. 3
• Grade 3
• 39 wks – post dates
• Complete indentations of
chorionic plate through to the
basilar plate creating
“cotyledons” (portions of
placenta separated by the
indentations)
• More irregular calcifications with
significant shadowing
• May signify placental dysmaturity
which can cause IUGR
• Associated with smoking, chronic
hypertension, SLE, diabetes

29. Unusual stuff
• CVS using uterine
manipulation with TVS
probe