• Dr Arun Gupta Director imaging

• Dr Rakhee guptaDr Vinayak Mittal

• Dr KiranDr Ritesh Mahajan

ADVANCED USG LOUNGE

FETAL ANOMALY ARCHIVE•ALOBAR HOLOPROSENCEPHALY

•SACROCOCCYGEAL CHORDOMA

•OMPHALOCELE

•TWIN –TWIN TRANSFUSION .

ALOBAR HOLOPROSENCEPHALY

It is a rare congenital brain malformation in which there is failure

of complete separation of the two hemispheres (which usually

occurs around the 4th

to 6th

weeks) and failure of transverse

cleavage into diencephlalon and telencephalon.

• single midline monoventricle (or holosphere) ( lateral and third ventricles are absent) .

• absent midline structures– Absent septum pellucidum.– Agenesis or hypoplasia of the corpus callosum .– Absent interhemispheric fissure and falx cerebri

• Dorsal cyst of holoprosencephaly .• Associated craniofacial features may also be

present which include– PROBOSCIS– Monoorbit / cyclopia– Mono – nostril – Hypotelorism– Cebecephaly .

• Classically three sub types have been recognised, however additional entities are now included in the spectrum of the disease. The three main sub types, in order of decreasing severity are:– Alobar holoprosencephaly.– Semilobar holoprosencephaly– Lobar holoprosencephaly.

• Other entities:– Syntelecephaly ( middle

interhemispheric variant MIH ) .– Septo-optic dysplasia .

• Other:– Central incisor syndrome – Nonspecific mid line dysplasia – Frontonasal dysplasia – Agnathia –otocephaly. Interorbital distane is reduced

Attenuation of the echogenicity of the Alveolar ridge of maxilla appreciated

MONOVENTRICLE FUSED CENTRAL GREY NUCLEI FUSED THALAMI CORTEX APPECIATED AS BALL LINING THE MONOVENTRICLE

HOLOSPHEREDEFICIENT ECHOGENICITY OF THE ALVEOLAR PREOCESS OF THE MAXILLA( FACIAL DYSGENESIS) . FUSED CENTRAL GREY NUCLEI .

Omphalocoele (or exomphalos) are congenital midline abdominal wall defects at the base of the umbilical cord insertion with herniation of gut (or occasionally other content) out of the fetal abdomen.

OMPHALOCELE

It is typically a large defect through which liver and/or bowel herniate and is covered by

a peritoneal membrane as well as amnion. The umbilical cord typically inserts at or near

the apex.

HERNIATION OF THE ABDOMEN CONTENTS

( GUT) .

On color / power dopplerThe cord insertion is on the

Apex of the defect .

Differential diagnosis

Gastroschisis: smaller para-umbilical defect usually to the right of midline, usually containing only bowel loops and not covered by a membrane .

Limb body wall complex : large defect usually to the left of midline umbilical hernia :

Physiological gut herniation: this diagnosis should only be entertained in early pregnancy prior to 11.4 weeks

SACROCOCCYGEAL CHORDOMA

SOFT TISSUE MASS SACRUM

Chordomas are uncommon malignant tumours that account for 1% of intracranial tumours and 4% of all primary bone tumours .They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the ratheks’ pouch to the coccyx). Since chordomasarise in bone, they are usually extraduraland result in local bone destruction. They are locally aggressive, but uncommonly metastasise.

Chordomas are found along the axial skeleton and a relatively evenly distributed among three locations:sacro-coccygeal: 30-50%spheno-occipital: 30-35%vertebral body: 15-30%

SACROCOCCYGEAL CHORDOMA

UMBILICAL CORD ADHERENT TO MASS

COLOR DOPPLER SHOWS VASCULARITY OF THE CHORDOMA

Mass in relation to femur and sacrum

TWIN – TWIN TRANSFUSION SYNDROME

Twin-to-twin transfusion syndrome (TTTS, also known as Feto-Fetal Transfusion Syndrome (FFTS) and Twin Oligohydramnios-Polyhydramnios Sequence (TOPS)) is a complication of monochorionic diamniotic (MCDA) pregnancy in which the presence of OLIGOHYDAMNIOS in one sac and POLYHYDRAMNIOS in the other sac results from intertwin vascular connections within the placenta.

RECEPIENT TWINFetal anasarcaFetal ascitesFetal pleural effusion.Prominent upper / Lower lip region ( subcutis edema)

Placentomegaly

RECEPIENT TWIN •Polyhydramnios•IUD•POG of 29wks

Donor twin •Live•Oligohydramnios.•POG of 28wks•Fetal Hypoxia . •IUGR

Stage five as per Quintero staging of twin twin transfusion

Syndrome.

Stage Ultrasound parameter Categorical criteria

I MVP of amniotic fluidMVP <2 cm in donor sac; MVP >8 cm in recipient sac

II Fetal bladder

Symptoms of Stage I except Donor has no measurable fluid, Nonvisualization of fetal bladder in donor twin over 60 min of observation

III

Symptoms of Stage II with Doppler anomalies in the Umbilical artery, ductus venosus, and umbilical vein

Absent or reversed umbilical artery diastolic flow, reversed ductusvenosus a-wave flow, pulsatile umbilical vein flow

IVSymptoms of Stage III with Fetal hydrops

Hydrops Fetalis in one or both twins

V Single or Double LossFetal demise of one or both twins

The Quintero staging of

twin-twin transfusion syndromeBecause there is no barrier separating the two fetuses from each other, there are almost always blood vessel connections in the placenta shared by two fetuses in monochorionic twin pregnancies. As a result of these connections, in about 10-15% of monochorionic twins (sharing one placenta) an imbalance in the circulations of the fetuses can develop. In these instances, there may be significant transfer of blood from one twin (the so-called “donor”) to the other twin (the so-called “recipient”), resulting in twin-to-twin transfusion syndrome (TTTS).

De Wikkellkinderen (The Swaddled Children), 1617, by an unknown artist, is thought to

depict TTTS.

First-trimester findingsCrown-rump length discordanceNuchal translucency >95th percentile or discordance >20% between twinsReversal or absence of ductus venosusA-wave).

Second-trimester findingsAbdominal circumference discordanceMembrane folding.

Velamentous placental cord insertion (donor twin)Placental echogenicity (donor portion hyperechoic)

DIAGNOSTICULTRASOUNDFOURTH EDITIONCarol M. Rumack, MD, FACRStephanie R. Wilson, MD, FRCPCJ. William Charboneau, MD, FACRRochester, Minnesota

REFERENCE