ultrasound

1. SHIFA
58TH BATCH

2. FIRST TRIMESTER SCAN
1) Assessment of early pregnancy & fetal
viability
2) Dating of pregnancy
3) Ectopic pregnancy
4) Multiple pregnancy
5) Hydatidiform Mole
6) Evaluation of first trimester bleeding.
7) Evaluation of uterus and adnexa

3. SECOND TRIMESTER SCAN
1) SURVEY
2) FOETAL BIOMETRY
3) FETAL ENVIRONMENT
4) PELVIC ANATOMY
5) TARGETED ANOMALY SCAN

4. • MOST IMPORTANT ASPECT OF 18-20 WEEKS
SCAN
• MOST OF THE ANOMALIES DETECTED
TARGETED ANOMALY SCAN

5. HEAD & NECK
CRANIAL VAULT
Absence of vault indicate
anencephaly.
Protrusion of cranial contents –
encephalocele.
Head shape & size
Lemon sign – scalloping of frontal bones ,
associated with spina bifida.
Strawberry skull – characteristic of
trisomy 18

6. LEMON SIGN

7. THREE PLANES
BPD plane.
With cavum septum pellucidum,falx, &
thalami.
Absence of midline structures –
holoprosencephaly.
Atrial plane.
To measure atria of the lateral
ventricles.
Dilatation of atria –ventriculomegaly,
increase in size of head.

8. Transcerebellar plane
To view posterior fossa with cerebellum & cisterna
magna.
Posterior fossa cyst with separation of cerebellar
hemisphere & absence of vermis – DANDY WALKER
MALFORMATION
Abnormal anterior curvature of cerebellar hemispheres –
BANANA SIGN- Spina bifida with Arnold Chiari malformation
Nuchal skin fold thickness measured in this plane B/N
occipital bone & skin is marker for 21 trisomy.
> 5 mm – abnormal
A cystic structure may be cystic hygroma.
May be septated or nonseptated – chromosomal
anomaly.
Neck

9. Cystic hygroma Banana sign

10. •SPINE
Visualised in sagittal, coronal &
transverse plane.
To identify spina bifida or a protrusion
as in meningocele

11. THORAX
Three areas
 thoracic wall
 Pleural cavity
 pericardial cavities
Three structures
 heart
 Two lungs

12. HEART
Visualised in transverse
section
Occupy one third of the
chest
Situs should be normal
left atrium nearest to spine
Two atria & two ventricles
should be of equal size

13. Septum primum,foramen ovale,interventricular
septum & atrioventricular valves are visualised
Rule out hypoplastic right or left heart,tetralogy
of Fallot,VSD, common atrioventricular canal
Outflow tracts are visualised to rule out
transposition of great vessels
The great vessels should cross each other & there
should be no dependent pericardial fluid

14. LUNGS
Lung resembles liver in
echogenicity
Presence of cystic structures
in thorax indicate congenital
cystic adenomatoid
malformation or a
diaphragmatic hernia
Pleural and pericardial
effusion is seen in hydrops
fetalis

15. ABDOMEN
THREE AREAS
Peritoneal cavity
Diaphragm
Abdominal wall
oDiaphragm visualised to rule out diaphragmatic
hernia
oOmphalocoele & gastroschisis are looked for.
oAscites seen in hydrops foetalis
THREE PLANES
Upper
Mid
Lower

16. Three planes
Upper abdomen
With stomach , portal vein & liver.
 DOUBLE BUBBLE SIGN of
stomach – duodenal atresia
Multiple dilated loops seen in
obstruction in lower part
Stomach not visualised in
oesophageal or diaphragmatic
hernia

17. Mid abdomen
Kidneys & small bowels
Renal agenesis, renal
pelvis dilatation and poly
cystic kidneys are looked
for.
Echogenic bowel – cystic
fibrosis & trisomy 21

18. Lower abdomen
Bladder & two umbilical arteries.
Bladder absent in renal agenesis.
Distended bladder in distal urethral
obstruction like posterior urethral valves
or urethral agenesis.
Presence of two umbilical arteries
coursing around the fetal bladder should
be confirmed.

19. EXTREMITIES
 Proximal, mid & distal segments are to be visualised
in each of the four limbs.
 Absence or hypoplasia looked for.
 All long bones visualised.
 If femur length is less other bones should also be
measured.
 Evaluated for length, echogenicity & shape.
 Gross shortening of all bones with a narrow chest -
thanatropic dwarfism.
 Decreased echogenicity & bowing or bending of the
long bones or fractures - osteogenesis imperfecta.
 Persistently clenched hands - trisomy 18
Check for talipes & rockerbottom feet.

20. FACE
Visualised in three
planes
Sagittal, coronal &
axial
To rule out cleft lip &
palate,
hypotelorism,hypertelori
sm & micrognathia.

21. UMBILICAL CORD
Three vessels of cord identified.
Two arteries & one vein.
Single umbilical artery associated
with malformations or twins.
Cord entry & placental attachment
noted.
Important in differentiating
between abdominal wall defects like
ompahocele & gastroschisis.

22. THIRD TRIMESTER SCAN
To assess fetal growth & wall being.
Not used to estimate gestational age.

23. Indications
Localisation of placenta after
32 weeks
Prediction of placenta acreta
Suspected intrauterine fetal
demise.
Confirmation of presentation

24. Fetal growth & well being
Fetal growth assessment based on biometry.
Abdominal circumference important to
determine IUGR.
BPD,FL,AC used to assess fetal growth.
Serial scan is more reliable.
Antepartum fetal surveillance include
NST,BPL and Doppler velocimetry.