ultrasound presentation

1. Ali Bendary
Assistant Lecturer
sonographic Fetal
anatomy at 18-23 weeks

2. history
• Echolocation in bats was discovered
by Lazzaro Spallanzani in 1794, when
he demonstrated that bats hunted and
navigated by inaudible sound and not
vision.
• The first technological application of
ultrasound was an attempt to detect
submarines by Paul Langevin in 1917.
(The term SONAR refers to Sound
Navigation and Ranging)

3. FaQ
Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

4. what is the best time For
anatomical scanning ?
• A routine mid-trimester ultrasound scan is often performed
between 18 and 22 weeks of gestation.
• Countries where pregnancy termination is restricted should
balance detection rates against the time needed for
counseling and additional investigation.
• Some centers perform the anatomical survey using
transvaginal scanning at approximately 13–16 weeks’
gestation.
ISUOG GUIDELINES 2013

5. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

6. what is the the aim oF the
routine mid-trimester scan ?
1- Confirm number and viability
of fetuses
2- Determine site of the
Placenta, assessment of
amniotic fluid and umbilical
cord.
3- Fetal biometry
4- Fetal anatomy
5- Fetal growth pattern
- estimation of GA and EFW
- assessment of fetal growth
(single - multiple)
6- Fetal wellbeing (BPP – Doppler)
7- Select patients requiring referral
to a tertiary center.
ISUOG GUIDELINES 2013

7. who should have a mid-trimester
Fetal ultrasound scan?
• all pregnant women should be offered an
ultrasound scan for the detection of fetal
anomalies and pregnancy complications.
ISUOG GUIDELINES 2013

8. First overview oF the Fetus
Psycological assurance
of the mother.
Broad view of the
fetus:
- Pulsating heart
- Profile of the face
- Both upper and
lower limbs

9. Standard viewsfor theexamination
of thefetus
1) The skull and brain
2) The face
3) The chest: heart and lungs
4) The abdomen: Diaphragm, stomach, liver,
kidneys, umbilical insertion
5) The spine
6) The limbs

10. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

11. the central
nervous system

12. Examination of thefetal brain is
essentially carried out by thethree
Transverseplanes:
• Transthalamic
• Transventricular
• Transcerebellar
NEUROSONOGRAM?

13. Trans-ventricular plane
Used for measurement of Va and Vp

14. • V/H ratio ? < 0.6 before 18 wks < 0.5 after 18 wks
• Used for measurement of BPD and HC
• Cephalic index: BPD/OFD = 80 ± 5
< 75 in doliocephaly > 85 in brachycephaly
Trans-thalamic plane

15. Trans-cerebellar Plane
- Called suboccipito-bregmatic view
- Allows examination of posterior fossa and mid-brain
- Used for measurement of TCD ( 13-21 wk? ), CM ( 2-10
mm ) and NF ( 6 mm )

17. NEUROSONOGRAM
Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

18. Spine
3 views: no spinal defects or
masses
-Sagittal
-Transverse
-Coronal
N.B. in sagittal view take care to
reduce the pressure on the
transducer to leave some amniotic
fluid between the proximal uterine
wall and the spine, which greatly
enhances the acoustic window

19. Cerebralventriculomegaly
- Grades: borederline (10-15mm) – moderate (15-20mm) – sever
(>20mm)
- Mild borderline (10-12mm) ?!!
- Unilateral in destruction and bilateral in cases of malformation
- Hydocephalus ?!!

20. Ventriculomegaly

21. Ventriculomegaly: diagnostic
work-up
• Detailed ultrasound exam including fetal echo
• Fetal neuro-sonography in 2nd T or MRI in 3rd T
• Karyotype (risk of triomy 21)
• TORCH screen

22. Holoprosencephaly
 defect in the development of the midline
embryonic forebrain.
Types :
- Alobar
- Semilobar
- Lobar

25. •Risk of chromosomal anomalies: This is high
(especially trisomy 13): up to 40% if other
malformations are associated.
•Risk of non-chromosomal syndromes: This is
relatively high: 15–20% of cases.

26. AGENESISOFTHECORPUS
CALLOSUM
It is the major commissure between the two
cerebral hemispheres

30. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

31. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

32. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

33. Posteriorcranialfossamalformations
Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

34. Open 4th
ventricle before 20 weeks
Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

35. DANDY–WALKER MALFORMATION
(DWM)
- Cystic dilatation of the 4th ventricle occupying the whole of the
cisterna magna
- Partial or complete agenesis of vermis
- upward displacement of tentorium
- Enlarged posterior cranial fossa

36. BLAKE’S POUCH CYST (BPC)
- Caudal expansion of the 4th
ventricle resulted in finger like
expansion of the PMA that does not perforate.
- Not communicate with subarachnoid space

37. MEGACISTERNA MAGNA (MCM)
- Enlarged CM which freely communicate with 4th
ventricle
and subarachnoid space
- Normal vermis
- Normal 4th
ventricle
- Normal tentorium
- Normal posterior cranial fossa

38. Hydancephaly
• huge fluid collection filling the whole cranial cavity,
• no recognizable cerebral cortex.
• The falx is usually present
• the meninges, thalami, basal ganglia, brainstem, and
cerebellum may be normal.

39. NEURAL TUBE DEFECTS
1-
ACRANIA/EXENCEPHALY/ANENCEPH
ALY
2- CEPHALOCELE
3- SPINA BIFIDA

40. ACRANIA/EXENCEPHALY/ANENCEPHAL
Y
• Acrania: Absence of the cranial
vault.
• Exencephaly: cerebral hemispheres
visible in the amniotic fluid 
‘Micey mouse’ appearance
• Anencephaly: no cerebral cortex
remaining  Frog appearance of the
orbits in the 2nd trimester (brain
destroyed)

41. Exencephaly

42. Pan Arab Conf for UMK of GYn
OBS ultrasound 2nd May 2006

43. Anencephaly

45. CEPHALOCELE
• Cystic structure protruding through a calvarial bone defect.
• The herniated anatomic structures can consist of meninges
only (meningocele) or meninges plus cerebral tissue
(encephalomeningocele)
• Prognosis depends on: size, site, contents and associated
lesions.

50. D.D.
- Absence of
calvarial bony
defect
- Bilateral
cystic dilatation
at the back of
neck with thick
fibrous band
(nuchal
ligament)

53. SPINA BIFIDA
- Refers to defective fusion of posterior spinal bony elements.
-Spina bifida aperta = open spinal dysraphism (OSD)
-Spina bifida occulta = closed spinal dysraphism (CSD)
-Meningocele: herniation of the meninges through defect and
there is a skin covering with no neural tissue
-Myelomeningocele: herniation of the meninges with
involvement of neural tissue covered by thin membrane
-Myelocele: failure of the neural groove to close with
subsequent exposure of neural tissue (the placode is flush
with the cutaneous surface)

56. Ultrasound diagnosis
Indirect signs

57. CHIARI II MALFORMATION
• Small posterior fossa
• Obliterated CM
• Dysmorphic cerebellum
( banana shaped)
• Ventriculomegaly
• Lemon sign
• Meningeo-myelocele

58. Direct signs
•axial and mid-sagittal planes: interruption of the cutaneous
contour at the level of the affected vertebrae
•axial views: the affected vertebra has a ‘C’ or ‘U’ shape,
which is due to absence of the dorsal arches
•coronal views: the lateral processes appear widely separated
(loss of normal divergent rail-track appearance)

61. TAKE HOME MASSAGE
(EFFECTIVENESS OF ULTRASOUND
EXAMINATION OF THE FETAL NEURAL
AXIS)
In a low risk pregnancy around mid-gestation, if:
The trans-ventricular plane, the trans-thalamic and the
trans-cerebellar plane are satisfactorily obtained.
 The head measurements (head circumference in particular)
are within normal limits for gestational age.
The atrial width is less than 10.0 mm.
The cisterna magna width is between 2–10 mm.
many cerebral malformations are excluded, the risk of a CNS
anomaly is exceedingly low and further examinations are not
indicated

63. THANK YOUTHANK YOU