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

Fetal anomaly series ………..

SPINA BIFIDA

OPEN ( Not covered with skin) . Elevation of MS AFP , associated with intracranial changesCLOSED ( Covered with skin) . MSAFP Normal . No intracranial changes.

CRANIAL SONOGRAPHIC FEATURES OF THE SPINA BIFIDA

• Non visualization of cistern magna • Deformation of the cerebellum (Banana sign)• Concave frontal bones (Lemon sign)• Dilatation of the lateral ventricles (Ventriculomegaly)• Chiari II malformation.

LEMON SIGN

 

Bifrontal scalloping / indentation.

Concave deformity of the fetal frontal bones

SHOULD Prompt detailed examination of the spine and posterior fossa

Can be seen in Normal fetus to diverse deformities :

Encephalocele

Dandy walker malformation

Thanatophoric dysplasia

BANANA SIGN

Spinal dysraphism leads to CSf leak and low intracranial pressure . This leads to effacement of the posterior fossa and cerebellum accommodates to the small space . The cerebellum wraps around the brain stem and appears as BANANA on transaxial scans . 

CHIARI MALFORMATION

EFFACEMENT OF THE CISTERNA MAGNA

CAUDAL PLACEMENT OF THE CEREBELLUM

OBLITERATION OF CISTERNA MAGNA

EFFACEMENT OF THE CISTERNA MAGNA

SMALL CEREBELLUM WITH REDUCED TRANCEREBELLAR

DIAMETRE

VENTRICULOMEGALY

Due to prominent ventricles

The dependant Choroid plexus appears drooping /dangling .

DEFICIENT CENTRUM OSSIFICATION IN SACRUM

Diagnostic Ultrasound 4th EditionCarol M. RumackStephanie R. WilsonJ. William CharboneauDeborah Levine

REFERENCE