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== Introduction ==
== Introduction ==
[[Image:ultrasound12wk_3D.jpg|thumb|300px|Ultrasound Imaging planes]]
[[Image:ultrasound12wk_3D.jpg|thumb|300px|Ultrasound Imaging planes]]

Revision as of 14:43, 24 February 2014

Embryology - 29 Mar 2024    Facebook link Pinterest link Twitter link  Expand to Translate  
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Introduction

Ultrasound Imaging planes

This page links to all ultrasound movies of live normal human embryos. Ultrasound imaging began in the 1950's but it was only with the application of computer analysis beginning in the 1980's that more detailed images could be generated.


Parents now commonly see ultrasound movies or images in the first trimester and clinically this is a non-invasive prenatal diagnostic tool for detection of abnormalities as well as a method of staging (ageing) and checking growth. There are several different standards available[1] for calculating age based upon several measurements, including embryo or fetal crown rump length (CRL).[2]


Ultrasound can also be used in combination with other techniques to locate both embryo and placenta for other prenatal tests (More? prenatal diagnosis).

The ultrasound technique can be used at any stage during pregnancy for fetal and placenta monitoring (More? Placenta Development | Placenta Abnormalities | Prenatal Diagnosis).


<mediaplayer width='550 height='400' image="http://php.med.unsw.edu.au/embryology/images/2/25/Ultrasound12wk_3D_image2.jpg">File:Ultrasound_Fetus_02.mp4</mediaplayer> Movie help 01.jpg

The ultrasound movies can be viewed in two ways:

  1. Clicking either the movie image or "Page" text below the image opens a new page with both the movie and a more detailed text description of features. Embedded movies then play by clicking the play triangle icon lying over the movie image.
  2. Clicking on the "Play" link will open the MP4 movie version alone on a new page.

Abnormal developmental ultrasound and features are listed on a separate page (More? abnormal ultrasound) all content is for educational use only.

Page | Play
Movie shows a 12 week fetus in 3d in realtime (hence 4D).
Special thanks to Dr Andrew McLennan, Foetal Medicine Unit, Royal North Shore Hospital for many of the original video materials.


Diagnosis Links: Prenatal Diagnosis | pregnancy test | amniocentesis | chorionic villus sampling | ultrasound | Alpha-Fetoprotein | Pregnancy-associated plasma protein-A | Fetal Blood Sampling | Magnetic Resonance Imaging | Computed Tomography | Non-Invasive Prenatal Testing | Fetal Cells in Maternal Blood | Preimplantation Genetic Screening | Comparative Genomic Hybridization | Genome Sequencing | Neonatal Diagnosis | Category:Prenatal Diagnosis | Fetal Surgery | Classification of Diseases | Category:Neonatal Diagnosis

| Abnormal Ultrasound

Some Recent Findings

  • 13-14-week fetal anatomy scan: a 5-year prospective study[3] "To assess the potential value of an early (first-trimester) ultrasound examination in depicting fetal anomalies by transabdominal (TAS) and transvaginal (TVS) sonography, to compare it with the traditional mid-trimester anomaly ultrasound examination and to evaluate the degree of patient acceptance of early sonography by the transvaginal route. ...TVS was significantly better in visualizing the cranium, spine, stomach, kidneys, bladder and upper and lower limbs (P < 0.001). Complete fetal anatomical surveys were achieved by TAS in 64% of cases versus 82% of the cases in which it was attempted by TVS (P < 0.001). ...Besides its importance in screening for chromosomal abnormalities, the early scan has great potential in visualizing with precision fetal anatomy. TVS can be used to compliment difficult TAS examinations; however, patients do not always agree to undergo TVS. The mid-trimester scan remains crucial for detailed fetal anatomical survey."
  • Comparison between ultrasound and magnetic resonance imaging in assessment of fetal cytomegalovirus infection[4] "MRI can provide important additional information with regard to abnormal gyration, cerebellar hypoplasia, or abnormal signal in white matter. It is certainly useful in the assessment of fetuses with extracerebral features without brain abnormalities detected with ultrasounds. If the fetal ultrasound is strictly normal in an infected fetus, MRI may not detect brain anomalies; however, it seems difficult to not perform this noninvasive procedure."
  • Prenatal diagnosis of vasa previa through color Doppler and three-dimensional power Doppler ultrasonography[5] "Vasa previa occurs in pregnancy when one of the membrane vessels extends down to the level of the internal cervical os, ahead of the fetal presenting part and unsupported by the placenta tissue or umbilical cord. The rupture of the vessels might happen spontaneously or artificially and frequently results in fetal exsanguination and demise. Ultrasound prenatal diagnosis is highly important as it allows the identification of patients at risk, thus an elective cesarean can be performed before rupture the membranes. We report a case of vasa previa diagnosed through color Doppler mode in the 30th week of gestation, emphasizing the contribution of three-dimensional power Doppler to the adequate mapping of aberrant vessels, which greatly contributed to the success of the perinatal result."

Ultrasound Movies

Normal Ultrasound
Ultrasound12wk 3D image2.jpg
 ‎‎Ultrasound 12wk
Page | Play
Week12 fetal heart rate-icon.jpg
‎‎12 Week Heart Rate
Page | Play
19weeklabel1.jpg
 ‎‎19 Week Fetus
Page | Play
  
Ultrasound day16 rabbit.jpg
 ‎‎Rabbit Embryo
Page | Play
Ultrasound: normal movies | abnormal movies | all ultrasound movies | Movies
Abnormal Ultrasound
Uterus Cleft Lip
Ectopic 01.jpg
 ‎‎Ectopic Pregnancy
Page | Play
Bicornuate uterus ectopic movie icon.jpg
 ‎‎Bicornuate Ectopic
Page | Play
Cleft lip 01.jpg
 ‎‎Cleft Lip 18 Week
Page | Play
Cleft lip 02.jpg
 ‎‎Cleft Lip 15 Week
Page | Play
Gastrointestinal Neural
Gastroschisis 01.jpg
 ‎‎Gastroschisis
Page | Play
Omphalocele 01 icon.jpg
 ‎‎Omphalocele
Page | Play
US Dandy-Walker 01.jpg
 ‎‎Dandy-Walker
Page | Play
US Spina bifida GA19week.jpg
 ‎‎Spina Bifida
Page | Play
Cardiac
US Transposition great arteries.jpg
 ‎‎Heart TGA
Page | Play
Hypoplastic left heart syndrome movie icon.jpg
 ‎‎Hypoplastic Left
Heart Syndrome
Page | Play
Postnatal persistant ductus venosus ultrasound 03.jpg
 ‎‎Patent
Ductus Venosus
Page | Play
Placenta
US Placenta Previa GA33week icon.jpg
 ‎‎Placenta Previa
Page | Play
US Vasa Previa GA32week.jpg
 ‎‎Vasa Previa
Page | Play
Velamentous cord movie icon.jpg
 ‎‎Velamentous Cord
Page | Play
Ultrasound: normal movies | abnormal movies | all ultrasound movies | Movies

Animal Ultrasound

Ultrasound day16 rabbit.jpg
 ‎‎Rabbit Embryo
Page | Play

4D Ultrasound

Fetal Face

Fetal facial expression 01.jpg Fetal facial expression 02.jpg
(a) 24 weeks (b) 27.5 weeks (c - d) 32 weeks. [6] (a) 28 weeks neutral face (b) 33 weeks (c) 32.5 weeks (d) 33 weeks.[6]

3D Ultrasound

3D Ultrasound Imaging
3D Ultrasound 12 week fetus

Three dimensional (3D) ultrasound scan images are generated from a series of images in 3 different planes. The image shows a 12 week fetal ultrasound images in the sagittal, axial and coronal planes that are used by the computer to generate the final 3D image in the lower right. Computers are able to generate these images in realtime, therefore in addition to static pictures, realtime 4D movies can be generated.


Heart

The heart is the first organ in the embryo that can be easily ultrasound visualised by its contractility. The absence of contractility also being a early diagnosis of embryo/fetal demise or trophoblastic disease.

The use of ultrasound at later stages of heart development in the mid-1980's began to be used as a diagnostic tool for congenital cardiac abnormalities.[7]

Soft Markers

The term "soft markers" refers to ultrasound measurements which may not be diagnostic by themselves, but can have an indicative role for further diagnostic analysis of the pregnancy.

The Diagnostic Imaging Committee of the Society of Obstetricians and Gynaecologists of Canada in 2005[8] made the following recommendations:

  1. The screening ultrasound at 16 to 20 weeks should evaluate 8 markers, 5 of which (thickened nuchal fold, echogenic bowel, mild ventriculomegaly, echogenic focus in the heart, and choroid plexus cyst) are associated with an increased risk of fetal aneuploidy, and in some cases with nonchromosomal problems, while 3 (single umbilical artery, enlarged cisterna magna, and pyelectasis) are only associated with an increased risk of nonchromosomal abnormalities when seen in isolation (II-2 B).
  2. Identification of soft markers for fetal aneuploidy requires correlation with other risk factors, including history, maternal age, and maternal serum testing results (II-1 A).
  3. Soft markers identify a significant increase in fetal risk for genetic disease. Timely referral for confirmation, counselling, and investigation is required to maximize management options (III-B).

Neural

Anencephaly ultrasound.jpg

Anencephaly ultrasound[9]

Doppler Ultrasound

Doppler ultrasound is a noninvasive measure of blood flow and blood pressure by bouncing ultrasound off circulating red blood cells. Originally used for fetal heart beat detection, more recently used diagnostically in uterine, placental, ductus venosus and other fetal blood vessels.

Doppler effect is due to the movement of blood cells causing a change in pitch of the reflected sound waves.

Ultrasound Placenta

Placenta Previa

Placenta previa - anterior.jpg Placenta previa ultrasound 01.jpg
Anterior placenta position (upper arrow) in relation to cervix os (lower arrow). Posterior placenta position (arrow) in relation to cervix os (triangle).
Links: Placenta Abnormalities

Placental Cord

A number of clinical and diagnostic measurements can be made from ultrasound scans of the placental cord, including its insertion site with the placenta. Key measures are blood vessel number, measured by cross-sectional scan, and blood flow, measured by colour doppler.

Cord

    • length (cm)
    • cross-sectional area (mm2)
    • coiling index
    • Wharton’s jelly area (mm2)
  • Artery
    • cross-sectional area (mm2)
    • pulsatility index
  • Vein
    • cross-sectional area (mm2)
    • absolute blood flow (ml/min)
    • blood flow for fetal weight (ml/kg/min)
    • blood flow mean velocity (cm/second)


Ultrasound Research

Ultrasound imaging began in the 1950's but it was only with the application of computer analysis beginning in the 1980's that more detailed images could be generated. The increasing quality of ultrasonic equipment and computing allows today realtime 3D scans and calculations of fetal measurements as well as doppler measurement of heart rates.

In medical research there have been recent developments that allow spatial high resolution down to 30 microns in real-time.


Other Imaging Techniques

There are a range of other imaging techniques to study development and used in developmental research.

Other developmental research imaging techniques include:

  • Magnetic Resonance Imaging
  • Computed Tomography
  • high frequency ultrasound or High Intensity Focused Ultrasound (HIFU)
  • positron emission tomography (PET)
  • single photon emission computed tomography
  • optical bioluminescence
  • fluorescence

Additional Images

References

  1. <pubmed>11065037</pubmed>
  2. <pubmed>20350241</pubmed>
  3. <pubmed>20205205</pubmed>
  4. <pubmed>18551722</pubmed>
  5. <pubmed>16903253</pubmed>
  6. 6.0 6.1 Reissland N, Francis B, Mason J, Lincoln K (2011) Do Facial Expressions Develop before Birth? PLoS ONE 6(8): e24081. doi:10.1371/journal.pone.0024081 PLoS One
  7. <pubmed>3923046</pubmed>
  8. <pubmed>16100637</pubmed>
  9. <pubmed>21042439</pubmed>


Books

Molecular Imaging and Contrast Agent Database (MICAD) NBK5330 | PMID:20641179

Search PubMed

Search PubMed: Ultrasound prenatal diagnosis | Ultrasound


Prenatal Diagnosis Terms

  • blastomere biopsy - An ART preimplantation genetic diagnosis technique carried out at cleavage stage (day 3), excluding poor quality embryos, detects chromosomal abnormalities of both maternal and paternal origin. May not detect cellular mosaicism in the embryo.
  • blastocyst biopsy - An ART preimplantation genetic diagnosis technique carried out at blastocyst stage (day 4-5), removes several trophoblast (trophoderm) cells, detects chromosomal abnormalities of both maternal and paternal origin and may detect cellular mosaicism.
  • cell-free fetal deoxyribonucleic acid - (cfDNA) refers to fetal DNA circulating and isolated from the plasma portion of maternal blood. Can be performed from GA 10 weeks as a first-tier test or as a second-tier test, with women with increased probability on combined first trimester screening offered cfDNA or diagnostic testing.
  • false negative rate - The proportion of pregnancies that will test negative given that the congenital anomaly is present.
  • false positive rate - The proportion of pregnancies that will test positive given that the congenital anomaly is absent.
  • free β human chorionic gonadotrophin - beta-hCG subunit of hCG used as a diagnostic marker for: early detection of pregnancy, Trisomy 21, spontaneous abortion, ectopic pregnancy, hydatidiform mole or choriocarcinoma.
  • multiples of the median - (MoM) A multiple of the median is a measure of how far an individual test result deviates from the median and is used to report the results of medical screening tests, particularly where the results of the individual tests are highly variable.
  • negative predictive value - The probability that a congenital anomaly is absent given that the prenatal screening test is negative.
  • Non-Invasive Prenatal Testing - (NIPT) could refer to ultrasound or other imaging techniques, but more frequently used to describe analysis of cell-free fetal DNA circulating in maternal blood.
  • polar body biopsy - (PB biopsy) An ART preimplantation genetic diagnosis technique that removes either the first or second polar body from the zygote. As these are generated by oocyte meiosis they detects chromosomal abnormalities only on the female genetics.
  • positive predictive value - The probability that a congenital anomaly is present given that the prenatal screening test is positive.
  • prenatal screening sensitivity - (detection rate) The probability of testing positive on a prenatal screening test if the congenital anomaly is present.
  • prenatal screening specificity - The probability of testing negative on a prenatal screening test if the congenital anomaly is absent.
  • quadruple test (maternal serum testing of a-fetoprotein Template:AFP, free B-hCG or total hCG, unconjugated estriol, and inhibin A) is a fetal chromosomal anomaly test usually carried out later in pregnancy (GA 14 to 20 weeks).
  • single nucleotide polymorphisms - (SNPs) the variation in a single DNA nucleotide that occurs at a specific position in the genome.
  • triple test - (maternal serum testing of a-fetoprotein Template:AFP, free B-hCG or total hCG, and unconjugated estriol) is a fetal chromosomal anomaly test usually carried out later in pregnancy (GA 14 to 20 weeks).


Other Terms Lists  
Terms Lists: ART | Birth | Bone | Cardiovascular | Cell Division | Endocrine | Gastrointestinal | Genital | Genetic | Head | Hearing | Heart | Immune | Integumentary | Neonatal | Neural | Oocyte | Palate | Placenta | Radiation | Renal | Respiratory | Spermatozoa | Statistics | Tooth | Ultrasound | Vision | Historic | Drugs | Glossary

Terms

  • Biparietal diameter (BPD)
  • Crown-Rump Length (CRL)
  • Femur length - (FL) is used to determine fetal age and normal development (small/large/abnormal) parameters. The femur is the longest bone in the body and measurements and reflects the longitudinal growth of the fetus (approximately 14 weeks 1.5 cm - term 7.8 cm). It is one of the four typical ultrasound assessments of fetal size and age: Biparietal Diameter (BPD), Head Circumference (HC), Abdominal Circumference (AC), and Femur Length (FL).
  • Functional linear discriminant analysis (FLDA) - new growth assessment technique using serial measurements to discriminate between normal and abnormal fetal growth.
  • Head Circumference (HC)
  • Gestational sac (GS) size
  • inversion mode - an ultrasound processing method of volume analysis for the visualization of fluid-filled fetal structures such as; heart chambers, vessel lumen, stomach, gallbladder, renal pelvis, and the bladder. Post-processing inverts the gray scale of the volume voxels showing the normally anechoic structures in 3D or 4D renderings. This technique has been used to identify cardiac anomalies.
  • Linear discriminant analysis (LDA) to longitudinal data (James and Hastie, 2001)
  • Mean gestation sac diameter (MSD)
  • Mean yolk sac diameter (MYD)
  • Spatiotemporal image correlation (STIC) - an image acquisition method used mainly for fetal heart analysis. Requires two steps; an automatic volume sweep, then image data analysis according to spatial and temporal domain generating an online dynamic 3D image sequence.
  • Transvaginal scan (TVS)
  • Termination of pregnancy (TOP)

External Links

External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource with no clinical information or commercial affiliation.


Glossary Links

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Cite this page: Hill, M.A. (2024, March 29) Embryology Ultrasound. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Ultrasound

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G