1. ADVANCED USG LOUNGE
SPIRAL CT MRI PET-CT
CENTRE SEC 44 –C
CHANDIGARH
www.spiralctmricentre.com
Dr Arun Gupta
Director imaging
Dr Rakhee gupta
Dr R K S Gandhi
Dr Vinayak Mittal
Dr Ritesh Mahajan

2. SONO EMBRYOLOGY

3. SONO EMBRYOLOGY
 VITTELOINTESTINAL DUCT

4. VITELLOINTESTINAL DUCT /YOLK STALK
OMPHALOMESENTERIC DUCT
The endodermal
connection between the
mid-gut and the yolk
sac. During embryonic
disc folding (human
week 3) this structure is embroy
Yolk sac
initially a broad open
connection which is then
restricted to a narrow
tube and finally closed
between the mid-gut
and the yolk sac.

5. YOLK SAC ATTTACHED TO EMBROY THROUGH
VITTELOINTESTINAL DUCT

6. The constituents of the vitelline duct
 vitelline veins ( Paired)
 (omphalomesenteric vein,The blood vessels
which form in the yolk sac and have a blood
flow towards the embryo. Derived from the
extra-embryonic mesoderm surrounding the
endoderm of the yolk sac.
 vitelline arteries ( Paired) .
 (omphalomesenteric artery The blood vessels
which form in the yolk sac and have a blood
flow away from embryo. Derived from the
extraembryonic mesoderm surrounding the
endoderm of the yolk sac.
 Vitellogenesis
 The term refers to the formation of yolk.

7. Doppler values of Vitelline artery
 Low velocity
 No diastolic flow
 PSV : 5.8 +_1.7cm/sec
 PI : 3.24 +_.94

8. 3D Rendered image

9. Fetal anomaly series ………..
ARACHNOID CYST

10. Arachnoid cyst …..a brief
Arachnoid cysts are benign intracranial
non communicating collections in the arachnoid
memberane.
 USUALLY STABLE
 CAN OCCUR INTRACRANIALLY OR IN SPINAL CANAL ALSO.
 EVEN IF LARGE ( RARELY CAUSE SYMPTOMS)
 MID LINE CYSTS MAY LEAD TO PITUITARY DYSFUNCTION.
 MAY INTERFERE WITH CSF CIRCULATION.
 COMMON LOCCATIONS ARE :
1. SYLVIAN FISSURE / TEMPORAL FOSSA
2. POSTERIOR FOSSA
3. ALONG CEREBERAL CONVEXITY
4. MIDLIINE ( SUPRASELLAR)

11. ARACHNOID CYST ………….
FETAL MR IMAGE
CSF SIGNAL LARGE
CYSTIC LESION IN THE
LEFT TEMPORO-
PARIETAL REGION
( SYLVIAN FISSURE
CONFINES)/SUPRASELL
AR / POSTERIOR
FOSSA REGION.
( NEARLY OCCUPYING
ALL THE COMMON
SITES WHERE
ARACHNOID CYST IS
PRESENT )

12. Fetal MR and Multiplanar USG Reformation.
FETAL MR SAGITTAL IMAGE
USG SECTIONAL PLANE IMAGING
MASS EFFECT IS APPRECIATED ON OF LARGE INTRACRANIAL CYST
BRAIN STEM INDENTATED ALONG
THE VENTRAL SURFACE

13. Coronal images ….Fetal MR / USG
NORMAL VERMIS / CEREBELLAR
HEMISHERE( RULES OUT DANDY- USG ( CORONAL PLANE )
WALKER MALFORMATION)

15. DIFFERENTIAL DIAGNOSIS
FOR ARACHNOID CYST
DEPENDS ON POSITION
 MIDLINE  Posterior fossa :
 Cavum veli interpositi
 Dandy walker
 Aneurysm of vein of
galen malformation
( Midline cysts may  Inferior vermian
accompany corpus hypoplasia
callosum dysgenesis
 Mega cisterna magna
so in supratentorial
cysts corpus callosum  Blake’s pouch cysts
should be assessed) .

16. References
Diagnostic Ultrasound
4th Edition
Carol M. Rumack
Stephanie R. Wilson
J. William Charboneau
Deborah Levine