Umbilical cord knots:

color doppler image<< Color doppler image of knot

color doppler cord knot

post delivery snap of cord knotPost delivery by Caesarean section

picture of cord knot

                                                     There are 2 types of knots in the umbilical cord: true knots and false knots.

False knots are actually kinks in the cord and have little clinical importance.

True knots can produce fetal death and are rare (1% of pregnancies). These usually occur in polyhydramnios with resultant increased fetal movement. We present ultrasound images of true knot of the umbilical cord, that was diagnosed on color Doppler imaging. This was confirmed after Caesarean section delivery.

Case and images by Dr. Gidda Ramaiah, India.


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Multicystic dysplastic kidney (MCDK):


Ultrasound images of this 20 week old fetus show multiple cysts of varying sizes involving both kidneys. This suggests bilateral multicystic dysplastic kidneys. There are two types of MCDK:

 a) the classical type (seen in this case)

 b) the hydronephrotic type.

Bilateral MCDK is not compatible with extrauterine survival of the fetus, as the affected kidneys would be non-functional. The typical MCDK shows the kidneys replaced by cysts resembling a bunch of grapes.

Images courtesy of Dr. Nirmali Dutta, UAE.

References: (complete article is free) 

Fetal gall bladder calculi:

The ultrasound scan images of this 3rd trimester fetus revealed multiple echogenic foci in the fetal gall bladder. They are seen as a string of foci with a thin crescent of hypoechoic fluid (bile) alongside the foci. This type of sonographic appearance is almost typical of gall bladder calculi. Very often the fetal gall bladder may be poorly distended, causing this ultrasound appearance to be confused with more ominous conditions like hepatic calcifications (due to cytomegalo-virus or toxoplasmic infections) or meconium peritonitis. The main point to be noted here is the typical position of the gall bladder in the right upper quadrant of the fetus, in proximity to the fetal liver. The ultrasound images in this section of the gallery show little or no acoustic shadowing. Fetal gall bladder calculi are a benign condition and have little clinical significance. They usually resolve spontaneously, during immediate postnatal period, if not during intrauterine life.

  Images courtesy of Dr. Ravi Kadasne, UAE.

  Reference:  (This complete article is free)


 Yet another case of parasitic twin:

This is another case of parasitic twin. Here, the parasite is incompletely developed with trunk lacking a heart, a shared liver, and a cranium with absent brain. It also had a few bowel loops (fluid filled) and limbs. The twins were successfully separated.

Images courtesy of Dr. Durr-e- Sabih, Pakistan.

The first images show ultrasound scan of the twins. CT scan images are added below that.

Lastly, snaps of the twins taken after delivery, are also present.





A rare case of bilateral renal agenesis in a fetus:

The ultrasound images show an extremely rare congenital anomaly, wherein both kidneys are absent in the fetus. The renal fossae in this case are partially occupied by the elongated adrenal gland. The distended urinary bladder is not seen. There is also associated oligohydramnios. Color doppler imaging reveals absence of the renal vessels.

The most important feature to note in this type of anomaly is absence of distended urinary bladder on repeated ultrasound scans. Besides, the other structures like bowel or adrenals, which occupy the renal fossae, donot show the typical hypoechoic medullary pyramids.

(Images courtesy of Dr. PK Srivastava, New Delhi, India).







Heteropagus or parasitic twin:

This is a very rare case of conjoint twins, wherein, a variable part of one twin is attached to or within a part of the other twin, which may appear, otherwise, grossly normal.

Types of heteropagus: 1) External- the parasitic twin is attached externally to the twin fetus. 2) Internal- this is the fetus in fetu. 3) Teratoma- a tumour within the twin.

4) Acardiac twin- this is a sort of parasitic twin connected via the placenta. The parasitic twin does not have a functional heart.

I present a rare case of external parasitic twin, wherein a complex mass of limbs and soft tissue, containing cystic areas are attached to the lower part of the face of the other twin (at 25 weeks gestation). Also attached are pictures showing the aborted fetus. I consider this case, an important addition to my ultrasound gallery.

Case and images courtesy of Dr.Gidda Ramaiah, India.

Reference: 1)



Ultrasound gallery- fetal spine- diastematomyelia:-

Diastematomyelia is a longitudinal (sagittal) cleft of the spinal cord, either complete or partial, by a bony, fibrous or cartilaginous septum. It usually involves the lower thoracic or the upper lumbar vertebrae. It is usually associated with spina bifida. Sonographically, it is best diagnosed around 18 weeks gestational age. The diagnostic finding is that of a bony spur in the centre of the spinal canal (see image below). This spur is best seen in the coronal section of the fetal spine. If a bony or cartilaginous septum or spur is not present, the diagnosis of this condition is rather difficult on ultrasound imaging. I consider the image below, an important addition to the ultrasound gallery of the fetus, as the bony septum is well seen in this case. Ultrasound image courtesy of Dr. V. Ganesan, Tamil Nadu, India.


  1) - Diastematomyelia -Gianluigi Pilu, MD



Sonographic diagnosis of club foot in a fetus:

(synonym- talipes equinovarus)

Club foot is a deformity of the foot characterized by:

The foot (and the heel in particular) is usually smaller than normal and pointing downwards. The front of the foot may point to the other foot. The bottom (sole) of the foot may point upwards (varus deformity).

Incidence: 1 to 3 per 1000 live births.

Etiology: it may be genetic (commonest) or postural (due to the position of the baby in the uterus). Genetically, if either parent or a sibling has clubfoot, the chances of the fetus also having this condition are higher. Besides, this type of clubfoot is associated with other anomalies of the heart or the palate (especially cleft palate). Trisomies 13 and 18 are also associated with clubfoot.

Ultrasound imaging in the diagnosis of clubfoot:                                                                       


In the normal fetus, on ultrasound, in a transverse section of the foot, the tibia and fibula should appear as echogenic specks above the foot. In club foot, see image below, the foot is parallel and not perpendicular to the adjacent part of the ipsilateral leg. Another sign that may be present, is that, the toes of the affected foot may be visible in the same section/ plane as the lower leg. In this addition to my ultrasound image gallery of the fetus, the left fetal foot shows this sign, diagnostic of clubfoot.

Images courtesy of Dr. V. Ganesan, Tamil Nadu, India.


Fetal goitre:

We have all heard and seen goitres in adult and children. But, few would have seen a goitre in a fetus. I present a case of fetal goitre diagnosed by ultrasound. Hence, the addition of this case to my ultrasound gallery. Fetal and maternal thyroid function independent of each other, under normal circumstances. However, if the mother is undergoing treatment for hyperthyroidism or is suffering from autoimmune diseases of the thyroid, the fetus may also develop thyroid disease, including goitre. Ultrasound scan should be done noting that the goitre may be visible only in the extended neck of the fetus. In this part of the ultrasound gallery, I have 2 ultrasound images, presented by Dr.V. Ganesan, Tamil Nadu, India. Transverse and sagittal ultrasound sections of the fetal neck are taken to demonstrate the fetal goitre.  See the image below (click for larger image).



1) [Diagnosis and therapy of fetal thyroid gland dysfunction in primary maternal disease]


Conjoint twins (thoraco-omphalopagus):

The above images (courtesy Dr. Durr-e- Sabih, Pakistan) show conjoint twins, in this case thoraco-omphalopagus or fusion of the thorax and abdomen. The ultrasound images show shared liver and heart. A multivessel cord is also noted.


 Yet another case of conjoint twins- thoraco-omphalopagus:

Courtesy of Dr. Arun Mahajan, India.

These images also show a shared liver and heart.


Conjoined twins are formed due to incomplete division of the embryonic disc and are fused at some portion of their bodies. Sonogrpahically, they are identified when the twins are in close proximity to each other, or when the sonologist is unable to separately identify the fetal bodies. Besides, one may find continuity of the skin of the fetuses with absent interamniotic/ intertwin membrane.

Reference: 1) - Twins, conjoined -Sandra Rejane Silva, MD2, Luís Flávio de Andrade Gonçalves, MD1, Philippe Jeanty...

2) - Twins, conjoined, thoraco-omphalopagus -Cheryl D. Norris, BS, Harris J. Finberg, MD, William Peoples



A live ectopic gestation:

(case courtesy of Dr. Nirmali Dutta, MD, UAE)

  A young female patient came with history of abdominal pain, localized to the right lower quadrant. Ultrasound scan revealed a large collection of free fluid in the abdomen. Careful examination on both transabdominal and transvaginal scan reveals an embryo of 6 weeks 6 days gestational age, in the right adnexal region, within a small sac. Color Doppler assessment of the sac shows evident fetal cardiac activity (heart rate of 155 beats per minute). In addition, a leash of blood vessels is visualized near the ectopic sac. The uterine cavity appears empty. 


1. Ectopic Pregnancy - Womens Health and Medical Information on
The above link would be useful to the lay person, but also gives a lot of information to the sonographer or sonologist.

2.  Basic Imaging > Ultrasound of Early Pregnancy
3.  Ectopic pregnancy - Wikipedia, the free encyclopedia

4. IngentaConnect Ectopic Pregnancy the Leash Sign. A New Sign on ... This describes the leash sign, a new sign that has a high sensitivty in ectopic pregnancy.




           This is an ultrasound scan (grey scale) image showing a profile of the normal fetal face. More than just a medical image, it gives a glimpse into the world of the fetus. Here, the fetus can be seen opening and then closing its mouth, possibly to yawn or swallow amniotic fluid. The other structures that are seen well in this ultrasound image are the nose and eye. Image courtesy of Dr. Vikas Arora, MD, Ferozepur, India.  


You can view ultrasound images of fetal cardiac anomalies at: Among the cardiac anomlalies presented here are DORV (Double outlet right ventricle) (with videos), fetal AVSD, ASD and fetal pericardial mass.