These days, ultrasound is one of the standard tests for pregnant women. To be precise, it is amongst the most significant tests that women go through.
However, the creation of the black and white image of a developing fetus arrived in the mids. During that time, experts used high-frequency sound waves to generate those images. So, you can comprehend that it is quite an old invention. So, today, we are going to discuss pregnancy ultrasound and some interesting facts about it.
It will help you to comprehend the ultrasound test better. So, here are the points that you must know. Well, in the year of , ultrasound was first used for medical purposes.
Glasgow was the place where it saw its first light. They were the first people who crafted the prototype system. They created it centered on an instrument that served the purpose of detecting the flaws in the industrial ships.
However, in the s, it became widely used. Now, we will fathom the working principle of the ultrasound scan. It will give you a clear notion about the functionality of this system. However, Manfred Hansmann did brilliant work with this machine. As I said, he pioneered invasive needling procedures under real-time control with this equipment, but when the ADR came into existence in , then everyone was able to get beautiful real-time images with a small manoeuvrable probe, so ultrasound guided invasive procedures quickly became the norm.
This is a typical ADR picture in You can see that the image looks a bit stripey, because at this time they had not learnt to interpolate scanning lines, but really the quality was actually quite good.
How about routine ultrasound scanning in pregnancy? I would like to claim that I was the first person who drew the attention of people that routine ultrasound was a desirable thing.
It is strange to think that it could take up to 10 minutes to measure a biparietal diameter in those days, when now we would expect to do all fetal biometry in the same period of time. Anyway, this is one prediction which has come to pass, because it has been demonstrated that routine second trimester biometry will reduce the number of unnecessary inductions of labour, as is demonstrated in the meta-analysis of 8 trials of routine versus selective ultrasound in pregnancy, where one of the significant advantages of routine ultrasound is reduction in the numbers of inductions for post-term pregnancies.
However, Persson and Grennert from the Malmo group were the first researchers to publish a study on routine ultrasound in pregnancy. You can see that they started in and published in The first national programme for routine ultrasound scanning was in the Federal Republic of Germany and I think there is no doubt they were influenced by the persuasive powers of Manfred Hansmann; they recommended two routine scans for all women.
They did produce a list of seventeen indications for an antenatal scan, which could allow for liberal interpretation, but still basically in the United States you do not believe in routine scanning, which I have to say with current knowledge on the benefits of routine scanning is difficult to understand. I am putting this in very diplomatic language. All of these researchers and centres made singular contributions to the development of the ultrasound scanning techniques and the various applications to which ultrasound is put today.
In the following slides I will go through some of the seminal papers on the various applications of ultrasound in obstetrics and gynaecology, which have shaped the way in which ultrasound is practiced today. Fetal Biometry:. I had earlier in produced the first BPD growth curve, but the paper, I think, had a seminal influence on the construction of growth charts.
In , the Campbell and Wilkin paper on measurement of abdominal circumference was an important milestone because this remains the most important parameter in the assessment of fetal weight and nutrition. Fetal Anomalies :. Again I begin with one of my papers in , which was the early diagnosis of anencephaly followed by termination of pregnancy. This was in effect the beginning of early prenatal diagnosis by ultrasound and I followed this up a few years later with the early diagnosis of spina bifida.
The seminal paper on echocardiography was produced by Lindsey Allan in This was a really important development and her paper was an absolute classic, where she described the systematic planes of the heart to make the diagnosis of fetal abnormalities. It really was the beginning of fetal echocardiography. Finally, I would put on my list of seminal papers, Nicolaides paper on the intracranial signs lemon and banana for spina bifida.
This is a classic paper because it introduced the concept of screening for a major abnormality with a very simple screening technique, so it actually had a tremendous influence on our ability to diagnose spina bifida.
Fetal Chromosome Abnormalities:. The establishment for likelihood ratios for a particular nuchal translucency measurement meant that for the first time ultrasound could be demonstrated to be superior to biochemical methods in screening for karyotype abnormalities.
Invasive Procedures:. Ultrasound guided procedures were developed even before the advent of real-time scanning. The classic early paper by Bang and Northved in from Copenhagan described the use of a specially developed transducer with a central hole for the needle in order to reduce the risks of amniocentesis. Hobbins and Mahoney first described the use of ultrasound guided fetoscopy in Hobbins used this technique not just to examine fetal anatomy, but also obtain red blood cells from the surface of the placenta for the prenatal diagnosis of thalassaemia.
Then in , Charles Rodeck and myself described pure blood sampling from the cord insertion; it was the first time pure blood had ever been achieved and this paved the way for biochemical studies on the fetus. Then in , Daffos in Paris first described a technique to obtain pure fetal blood without the use of the fetoscope by directing the tip of the needle under ultrasound control directly into the cord insertion.
Daffos actually had a sonographer identifying the cord insertion, while he inserted the needle, but Nicolaides described the two-handed technique of cordocentesis, where the operator performed both scanning and needle insertion. Finally, of course the procedure of chorion villus sampling would not have become so wide spread and indeed the most important method of determining the fetal karyotype, were it not for the classic paper by Hahnemann in , where he described the transabdominal technique, which has pretty well confined the transcervical method to the dustbin of history.
Ultrasound Guided Therapeutic Procedures:. Although Hansmann, I believe, ultrasound guided intraperitoneal transfusion, I have put on my list of seminal papers the paper by Hobbins, as this was hugely influential in persuading people to abandon the old Xray method pioneered by Lilley. Charles Rodeck in first described fetoscopic intravascular transfusion, which overcame problems associated with absorption of fetal cells from the fetal peritoneal cavity. Nicolaides and Berkowitz separately described intravascular transfusion by cordocentesis very shortly after that.
Golbus, in San Francisco, and Berkowitz in New York were the first to describe the insertion of a vesico-amniotic amniotic shunt to relieve bladder obstruction due to posterior urethral valves. Although shunting procedures have subsequently been performed for this and many other indications, there is little proof that these are life saving procedures. Doppler Ultrasound:. We must begin with the first Doppler ultrasound paper on continuous wave assessment of umbilical artery flow, which was published in in the British Medical Journal by Fitzgerald and Drumm from Dublin.
This really was a seminal paper from a city with no big ultrasound tradition In , Sturla Eik-Nes, who was working in Mlmo, showed that fetal aortic velocimetry could be carried out using a duplex scanner, i. With the same system, I first described in in the Lancet, the assessment of the utero-placental circulation and that high resistance waveforms were obtained in pre-eclampsia.
Subsequently these studies were done with colour Doppler and in many centres this has become an important screening technique to predict women at risk of pre-eclampsia. With the use of colour Doppler, Wladimiroff pioneered the study of the middle cerebral artery in and the use of the middle cerebral to umbilical artery PI ratio to demonstrate centralisation of the fetal circulation.
In Kiserud completed the Doppler story by describing waveforms in the ductus venosus, which is now recognised as a key examination to predict right heart failure in the hypoxic fetus and the most important indicator of imminent fetal demise. Fetal Activity:. The first fetal activity to be studied was fetal micturition by Campbell and Wladimiroff in and they subsequently demonstrated that in IUGR fetuses, fetal urinary production was reduced.
With the advent of real-time scanning, detailed studies of fetal activity were produced. The group of Patrick in London, Ontario, was one of the first to document the incidence of fetal breathing movements over a 24 hour period. More detailed studies of fetal behaviour were given a stimulus by the paper of Birnholz on fetal eye movements.
Perhaps the most seminal paper produced on this subject was in when Manning and Platt described the biophysical score, which for 20 years has remained the most important method of assessing fetal wellbeing, certainly in the United States. Gynaecological Scanning:. Even before the advent of transvaginal sonography, which has now become the standard method of evaluating the pelvis to diagnose gynaecological conditions Kadar et al in had produced their seminal paper on the early diagnosis of ectopic pregnancy, describing the discriminatory zone of hCG, above which an intrauterine gestation sac should be visible.
Campbell et al in were the first to publish on a large scale 5 year screening project for ovarian cancer. Subsequent to this DePriest et al in Denver published similar encouraging reports on screening for ovarian cancer by transvaginal sonography.
Morphological scoring systems to improve the diagnosis of ovarian cancer in masses detected by ultrasound was carried out by several workers, but the paper of Sassone and Timor-Tritsch in remains the classic. Finally, Bourne and Kurjak both published papers advocating the use of colour Doppler in refining the prediction of ovarian cancer in ovarian masses. Granberg was the pioneer in using the measurement of endometrial thickness to predict endometrial cancer and the use of a 5 mm limit is used widely to exclude this disease.
Reproductive medicine:. Even before the advent of transvaginal sonography, Hackeloer working in Glasgow, described the growth of the ovarian follicle and correlated growth rates with oestrodial values. The paper by Susan Lenz in the Lancet was a seminal work, because for the first time it was demonstrated that eggs could be obtained from ovarian follicles directly under ultrasound control. Susan Lenz described a transvesical approach and I have to say it made a profound impression on me.
Then Dellenbach in described transvaginal egg collection by guiding a needle along a transvaginal probe and this has become the standard method for egg collection.
Researchers don't know exactly at what level this occurs, Nicolson said, adding that testing the threshold at which it becomes dangerous in humans would be unethical. He said that ultrasound scans should only be done for clinically justified reasons. For example, so-called "bonding scans," images taken purely for commemorative purposes, unnecessarily expose a fetus to the high-energy sound waves, Nicolson said. Ultrasound has enjoyed an enthusiastic reception by pregnant women.
In addition to revealing the baby's health, the images themselves provide a keepsake. In fact, Nicolson said, some women report not feeling pregnant until they've seen the ultrasound image. Seeing a developing fetus has a humanizing effect, too. Donald, the physician who helped develop the technology, was a devout High Anglican, and knew the images carried moral significance for women contemplating having an abortion.
Ultrasound images sometimes play a role in decisions to maintain or terminate a pregnancy. Anti-abortion proponents take ultrasound images as proof that a fetus is fully alive and therefore should not be aborted. On the other hand, ultrasound can be used to diagnose potentially fatal or debilitating abnormalities in the fetus, which can encourage termination of the pregnancy.
In some East Asian countries, ultrasound is used to detect the sex of the baby expressly so that a fetus of less desirable sex usually female can be aborted, Nicolson said.
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