1. Dr.Omneya Elmakhzangy
Special Fetal Care Unit
Ain Shams University
3D DOPPLER ULTRASOUND
IN OBSTETRICS

2. A HISTORICAL BACKGROUND
 In the past decade the use of 3D
ultrasonography moved from an
advertising toy highlighting the
baby's face to a new powerful tool in
perinatal diagnosis.

3. WHY DO WE USE 3D ACQUISITION
RATHER THAN 2D?
 The use of color and power Doppler in the
early 1990's has improved perinatal
diagnosis of complex C.V.S malformations
over the grey scale ultrasound.
 The draw back in using 2D color or power
Doppler is that they generally allow the
visualization of vessels running in a
straight course or lying on the same 2D
plane.

4.  In most cases the examiner has to
mentally reconstruct a spatial image
of the vessels examined.
 In recent years 3D Doppler has
helped in the reconstruction of the
vessels of interest and thus improves
the understanding of the spatial
appearance of the Vascular tree.
 The images acquired were close to X-
ray or MR angiography.

5. 3D POWER OR 3D COLOR DOPPLER
WHAT TO CHOSE?
 3D power Doppler offers a more sensitive
detection of the blood flow regardless to
its direction giving a unified color
mapping .
 The draw back in Power Doppler
compared to color Doppler is that it's
more susceptible to interference and
noise in addition to being unable to detect
different directions of flow within the
region of interest.

6. 3D Power Doppler

7. 3D COLOR DOPPLER

8. TECHNICAL BACKGROUND
 Two main aspects have to be taken in
consideration when acquiring a volume
image :
1- Volume Data Acquisition.
2-Image rendering .

9. VOLUME DATA ACQUISITION
There are two ways to achieve :
1- Static 3D mode which is a series of still
images.
2- A 4D mode which can be either by a
real time 3D scanning or an offline 4D
which is one of the recent advents in
the software that allows spatial and
temporal image correlation known as
"STIC".

10. IMAGE RENDERING
 It is the process of creating a 3D visual
presentation of parameters of interest.
 The main principle behind this is
"planar geometric projection" i.e a 2D
image to represent the 3D data the third
dimension impression is acquired
through online rotation of the image
along X , Y and Z axis

11.  The exam can show the vessel of interest
alone "Inversion mode" or along with the
gray scale image in what's called the
"Glass body rendering mode".

12. ARE WE LOOKING AT A VESSEL
OR AT A SPECIFIC ORGAN
VASCULARITY?
If a specific vessel is targeted we simply
apply 3D power or Color Doppler on the
vessel of interest but if an organ or a
structure as a whole is targeted we use a
software technology known as VOCAL
(virtual organ computer aided analysis).

13. OBTAINING THE IMAGE STEP
BY STEP
 1-Choose the 3D/4D probe to use for your
scan
 2- From the submenu of the 3D/4D probe
choose the application most appropriate
according to your case e.g gestational age
1st, 2nd and 3rd trimsteric scanning.
 3- Perform a usual real time 2D scan to
visualize and locate your organ or region
of interest .

15.  4- Press on the power or color Doppler button
to acquire a blood flow mapping.
 5- Adjust the box that's going show up on
your screen to include your area of interest
only.
 6- Press on 3D button and keep your hands
steady to acquire the volume.
 7- Once volume is acquired save it on your
machine to process it immediately or later but
make sure to save it as a 3D volume not a 2 D
image.

17.  8- Choose to perform volume analysis
from the submenu.
 9- Press on the VOCAL button which will
allow you to manually trace the volume at
a specified angles of rotation chosen by
the operator.

19. 10- Your ultrasound machine will give the
option of accepting you ROI " region of
interest" , once accepted you can then
choose the volume histogram which gives
you a numerical value of the vascular
indices.

21. QUANTIFYING THE BLOOD FLOW

22. 1- VI (Vascularization index): Vascularization
index is the ratio of the number of color voxels
(volumetric pixel) to the total number of voxels in
the sampled tissue, thus it represents the
percentage of vascularized tissue

23. 2- FI (flow index) : Flow index is the
average colour value of all colour
voxels and it describes the mean
velocity of flow in the sampled tissue.

24. 3- VFI (vascularization flow index) : is the
average colour value of all colour and
grey voxels and describes both: the
vascularization and the blood flow.

25. CLINICAL APPLICATIONS OF 3D
POWER DOPPLER IN OBSTETRICS

26. EARLY PREGNANCY

27.  Umbilical cord : true and false knots,
single umbilical artery and normal
and abnormal insertion in placenta.

28.  Placental anomalies as placenta previa , placenta
accreta or vasa previa.

29. Placental vascularity assessment for IUGR and PIH
disorders.

31. FETAL INTRA
ABDOMINAL VESSELS

32.  Currently the main field of interest seems to be
the absence of ductus venosus with different
possibilities of umbilical vein connection, in this
condition the role of 3D power Doppler is to
demonstrate the spatial course of the aberrant
vessel .

33. Abnormal site of intra-abdominal vessels in
gastroschisis

34. ABNORMAL CORD INSERTION IN
OMPHALOCELE

35. Abnormal umbilical vein size (varix or ectasia)

36. Another interesting condition is the abnormal
course of vessels in isomerism i.e the
interruption of inferior vena cava with
Azygous continuity

37. Visualization of renal vessels increase the
accuracy of diagnosis of renal
malformation as renal vascular tree is
easily demonstrated

38. Fetal cardiac circulation

39.  Extended fetal echocardiography can be
acquiring and documenting different cross
sectional planes in the heart.
 In the last decade the advent in 3D and 4D
(real time 3D) has allowed the operator to
automatically reconstruct the cardiac
circulatory system and its connection
spatially instead of doing it mentally as in
the past.
 A new software technique known as STIC
(spatiotemporal image correlation) has
allowed this automatic reconstruction.

41. Fetal cerebral circulation

42.  Many vascular malformation in the fetal
cerebral circulation can demonstrated by
the use of 3D power Doppler
reconstruction

43. NORMAL BRAIN VASCULARITY

44. 3D MULTIPLANAR VIEW AND POWER-
DOPPLER IMAGING OF A VEIN OF GALEN
ANEURYSM

45. INTRACRANIAL TUMORS

46. SUPERIOR SAGITTAL SINUS BY
BIDIRECTIONAL 3D POWER DOPPLER

47. Corpus Callosal agensis

48. A-V MALFORMATIONS IN
CEREBRAL CIRCULATION
 The 3D Power Angio reconstruction
demonstrates connection feeder and
draining vessels (arrows) of the vein of
Galen ectasia and sinuses of brain (ts –
transverses sinus, sps – superior petrosal
sinus)

50. CIRCLE OF WILLIS IN NORMAL
AND HOLOPROSENCEPHALY