Über die Möglichkeit, hochfrequente mechanische Schwingungen als diagnostische Mittel zu verwerten.
Zeitschrift gesamte Neurologie und Psychiatrie 174 (1942): 153–168
K.T. Dussik
Application of echo-ranging techniques
to the determination of structure of biological tissues.
Science 115 (1952): 226–230 J.J. Wild, J.M. Reid
The use of ultrasonic Reflectoscope for the continuous recording of the movements of heart walls.
Kungl. Fysiografiska Sällskapets I Lund Förhandlingar 24 (1954): 1–19
I. Edler, C.H. Hertz
The ultrasonic visualization of soft tissue structures in the human body.
Trans. Am. Clin. Climatol. Assoc. 66 (1954): 208–223 J.H. Holmes, D.H. Howry, G.J. Posakony, C.R. Cushman,
Investigation of abdominal masses by pulsed ultrasound.
Lancet i (1958): 1188–1195 I. Donald, J. MacVicar, T.G. Brown
Ultrasonic Doppler method for the inspection of cardiac functions.
J. Acoust Soc. Amer 29 (1957): 1181–1185 S. Satomura
Neue Möglichkeiten der Ultraschalldiagnostik in der Gynäkologie und Geburtshilfe.
Fortschritte der Medizin 84, 18 (1966): 689–693 D. Hofmann, H.-J. Holländer, P. Weiser
The prediction of fetal maturity by ultra-sonic measurement of the biparietal diamenter J Obstet Gynecol Br Gwith 76 (1969): 603–609 S. Campbell
Development of an ultrasonic system for three-dimensional reconstruction of the fetus.
J Perinat. Med. 17 (1989): 19–24
K. Baba, K. Satoh, S. Sakamoto, T. Okai, S. Ishii
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3 Ultrasound
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Introduction
The evolution of diagnostic ultrasonography has been the combined efforts of physicists, mechanical, electrical and bio-medical engineers, computer technolo- gists, clinicians, sonographers, researchers, university and government adminis- trators as well as adventurous and perceptive commercial enterprises. Diagnostic medical ultrasound had exclusively evolved from military technology used in mapping waves through liquid (Sonar by Richardson and Langévin, 1915-18), through air (Radar by Appleton and Watson-Watt, 1938) and through solids (pulse-echo method for non-destructive testing of metallic structures with the metal-flaw detector by Sokolov, 1940).
The association of ultrasonic with medicine dates from the late 1920s. Several investigation showed the biological effects of ultrasound on animal (Loomis, Wood 1927) and red blood cells (Johnson 1929). So it was obviously to start initial- ly with its applications in therapy rather than diagnosis. Ultrasonic physiotherapy became popular in the 1930s and was used in the treatment of arthritic pains, gas- tric ulcers, eczema, asthma, thyrotoxicosis, hemorrhoids, urinary incontinence, elephantiasis and even angina pectoris.
The problems in detecting soft tissues with X-rays, particularly the brain, led the Austrian neurologist/psychiatrist Karl Theodore Dussik from the University of Vienna to develop an idea to locate brain tumors and the cerebral ventricles by measuring the transmission of ultrasound beam through the skull. He can be re- garded as the first physician to have employed ultrasound in medical diagnosis.
He and his brother Friedrich, a physicist, used a through-transmission technique with two transducers placed on either side of the head, and producing what they called “ventriculograms”, or echo images of the ventricles of the brain. Later it could be shown that the images that Dussik produced were artifactual. In further experiments researchers at Siemens, Erlangen and the M.I.T. were able to show that the reflections within the skull and attenuation patterns produced by the skull were contributing to the attenuation pattern which Dussik had originally thought represented changes in acoustic transmissions through the cerebral ven- tricles in the brain. In conclusion, at this time ultrasound had no role to play in the diagnosis of brain pathologies.
Nevertheless, systematic investigation into using ultrasound as a diagnostic tool continued. In the late 1940s George Ludwig from Naval Research Institute in Bethesda, Maryland began experiments, exclusively for the Navy, on animal tissues using A-mode presentations of reflected echoes. Together with his collaborator F.W.
Struthers he was able to detect gallstones and foreign bodies embedded in tissues.
The pulse-echo A-mode devices developed from the reflectoscope/ metal flaw detectors were soon employed in experiments on several medical diagnosis. Using an industrial Siemens “Reflectroscope,” Inge Edler and Carl Hellmuth Hertz start- ed in Lund, Sweden in 1953, their important cardiac investigations, which were fol- lowed on by Sven Effert in Germany in 1956. As head of the Department of Cardiology at the University Hospital, Lund, Inge Edler was responsible for evalu- ating the cardiac patients prior to the surgical repair of mitral stenosis. Edler fi- nally established the characteristic motion pattern for the anterior leaflet of the mitral valve. He compared the shape of the fast-moving echoes in patients with enlarged hearts due to mitral stenosis during cardiac operations, and found em- pirically the shape correlated well with the severity of the stenosis. By early 1955, Edler had so much evidence of this relationship that he relied on ultrasound alone for the diagnosis of mitral stenosis. The typical time-motion patterns (M-mode) of other heart valves, pericarditis, tumors, and thrombosis in the left atrium showed up in the recordings and were identified by close cooperation with Dr.
Olle Dahlback’s heart surgery group. The advent of a barium titanate transducer
produced by Siemens in Germany in 1958 was an important advance for the group and enabled them to study not only the normal mitral valve but also many other heart structures. Sven Effert in Germany, who had been collaborating with Hertz in some of his work, futher demonstrated the usefulness of M-mode echocardiog- raphy, which subsequently caught on as a mainstay investigation in cardiology.
In conclusion, the A-scan did not provide sufficiently accurate, reproducible and interpretable information to allow a firm diagnosis to be made. It would not have a lasting impact on clinical medicine without evolving into the B-scan, which had its origin in military radar.
In 1951 J.J. Wild and his collaborator J.M. Reid constructed the first B-mode echoscope that was ultimately used to visualize tumors by sweeping from side to side through breast lumps in patient scheduled for surgery. This first clinical B- mode instrument incorporated a water column that bathed the transducers and was sealed at the tip with condom rubber, providing the water-delay. Thus, this was indeed the very first hand-held contact scanner for clinical use. In May 1953 they produced real-time images at 15 MHz of a 7-mm cancerous growth of the breast.
In 1948 the radiologist Douglas Houwry started his pioneering ultrasonic in- vestigations at the University of Colorado in Denver. His goal was to develop a new technique to display anatomical structures similar to the use of X-rays, and
“in a manner comparable to the actual gross sectioning of structures in the pathology laboratory”. He was able to demonstrate an ultrasonic echo interface between tissues, such as that between fat and muscle. Together with Joseph Holmes, the acting director of the hospital’s Medical Research Laboratories, and the two engineers William Rodderic Bliss and Gerald J. Posakony, Howry con- structed the first two-dimensional B-mode (or PPI, plan- position indication mode) linear compound scanner, and later on the motorized “Somascope”, a com- pound circumferential scanner, in 1954. The transducer of the somascope was mounted on the rotating ring gear from a B-29 gun turret, which in turn was mounted around the rim of a large metal immersion tank and was filled with wa- ter. The machine was able to make compound scans of an intra-abdominal organ from different angles to produce a more readable picture. The PAN-Scanner, where the transducer rotated in a semicircular arc around the patient, was devel- oped in 1957. The patient sat on a modified dental chair strapped against a plastic window of a semicircular pan filled with saline solution, while the transducer ro- tated through the solution in a semicircular arc. All of these systems, although ca- pable of producing 2-D, accurate, reproducible images of the body organs, re- quired the patient to be totally or partially immersed in water and remain mo- tionless for a length of time. Lighter and more mobile versions of these systems, particularly with smaller water-bag devices or transducers directly in contact and movable on the body surface of patients, were urgently required.
Although much of the earliest interest in diagnostic ultrasound was directed towards the detection of foreign bodies, tumors or echocardiography, some of the most successful clinical applications were found in the field of gynecology and ob- stretics. Ian Donald from the University of Glasgow’s department of midwifery, Scotland, was the first physician in these fields. Like many other colleagues, Donald was introduced to military applications of ultrasound during wartime.
Together with Tom Brown and John MacVicar and with support from the Kelvin &
Hughes Scientific Instrument Company, he plunged into an intensive investiga- tion into the value of ultrasound in differentiating between cysts, fibroids and any other intra-abdominal tumors that came their way. In 1957 Brown invented and constructed with Ian Donald the prototype of the world’s first compound B-mode (PPI) contact scanner. The transducer operated at 2.5 MHz. The first contact B-scanner was designed and built by Tom Brown on the frame of a hospital bed- table. The ‘bed-table’ scanner was manually operated. A compound sector tech-
nique was used to build up a two-dimensional image with gray scaling. This was the world’s first and only fully automatic scanner in order to give a consistent scanning pattern. Much of the early research was carried out with this machine.
Early results were disappointing and the enterprise was first greeted with a mix- ture of scepticism and ridicule. However, a dramatic case where ultrasound saved a patient’s life by diagnosing a huge, easily removable ovarian cyst in a woman who had been diagnosed as having inoperable cancer of the stomach made people take the technique seriously.‘From this point’, Ian Donald wrote,‘there could be no turn- ing back’. Results eventually appeared in print in The Lancet of 7 June 1958 under the arid title “Investigation of Abdominal Masses by Pulsed Ultrasound”. This was prob- ably the most important paper on medical diagnostic ultrasound ever published.
The first application in medicine of the Doppler effect to the study of movement involved the measurement of the difference in the transit time between two trans- ducers of ultrasound travelling upstream and downstream through flowing blood were demonstrated by Baldes et al in 1957. The Japanese physicists Shigeo Satomura and Yasuhara Nimura were the first to demstrate the Doppler shift in the frequency of ultrasound backscattered by cardiac valvular motion and pulsations of peripher- al blood vessels. In December 1955, Satomura published his first paper on the subject entitled “A new method of the mechanical vibration measurement and its applica- tion”. In this paper he demonstrated that Doppler signals can be retrieved from heart movements when insonated with 3 MHz ultrasonic waves. In 1966, K. Kato and T. Izumi developed a directional flow meter using the local oscillation method. In 1967, the Rushmer group outlined the use of Doppler ultrasound in obstetrics in an article in JAMA, “Clinical Applications of a Transcutaneous Ultrasonic Flow Detector”, which was confined basically to the detection of fetal life, placental loca- tion, blood flow through the uterine vasculature and fetal movements.
These early successes triggered a boom of new research and application of ul- trasound especially in gynecology and obstetrics. A- and B-mode equipment were both in use. The A-mode scan had been used for early pregnancy assessment (de- tection of fetal heart beat), cephalography and placental localization. B-Mode pla- centography was successfully reported in 1966, in 1969 to measure the gestational sac diameters in the assessment of fetal maturity and in 1971 in relation to early pregnancy complications. Stuart Campbell described in 1968 the use of both the A- and B-mode scan to measure the fetal biparietal diameter. His method, de- scribed in his landmark publication “An improved method of fetal cephalometry by ultrasound,” became standard for the next 10 years.
Using of the B-scan made an important technical improvement necessary. The storage or bi-stable cathode ray tubes that were used had a low dynamic range of about 16 decibels. Although there was good representation of size, shape and posi- tion, the images did not depict differences in echo amplitude. Gray-scaling was ur- gently necessary to expand the diagnostic capability and accuracy of a B-scan.
The most important innovation in ultrasound imaging subsequent to the in- vention of the compound contact scanner was the advent of the scan converter. In the mid-1950s machines such as that developed in Glasgow were actually gray- scale ready from the outset. Images could then be scaled, calipers moved and ap- plied on-screen (something that had changed entirely the way measurements are made), gray-scaling applied to the images and the resultant image recorded on a variety of media including videotape, emulsion films and thermal printer devices.
In 1964 the concept of the multi-element linear electronic arrays was first de- scribed by Werner Buschmann. Concepts of the real-time array (Bom 1971) and the phased-array scanning mechanism (Somer, 1968) paved the way for the con- cept of a linear-array system (Macovski, 1974)
The real revolution in diagnostic ultrasound started with the development of the real-time scanner at Siemens, Erlangen, Germany, by Walter Krause and
Richard Soldner together with Johannes Pätzold and Otto Kresse. This innovation soon completely changed the practice of ultrasound scanning. The manufactured
“Vidoson” used three rotating transducers housed in front of a parabolic mirror in a water coupling system and produced 15 images per second. The image was made up of 120 lines and basic gray-scaling was present. The use of fixed-focus large-face transducers produced a narrow beam to ensure good resolution and image.
Fetal life and motions could clearly be demonstrated. D. Hofmann, H.
Holländer and P. Weiser published its first use in obstetrics and gynecology in 1966 in the German language. Hofmann and Holländer’s paper in 1968 on
“Intrauterine diagnosis of hydrops fetus universalis using ultrasound” also in German, is probably the first paper in the medical literature describing formally the diagnosis of a fetal malformation using ultrasound. Hans Holländer, in anoth- er paper in 1968, demonstrated the usefulness of a ‘real-time’ scanner in the diag- nosis of ovarian tumors which were not spotted on pelvic examination. Malte Hinselmann, using the Vidoson, demonstrated in 1969 the universal visualization of fetal cardiac action from 12 weeks onwards. The Vidoson was popular in the en- suing 10 years or so and was used in much scientific work published from centers in Germany, Switzerland, Austria, Belgium, Italy and other European countries.
Visualization of the fetus in 3-D has always been on the minds of many investi- gators. Kazunori Baba, at the Institute of Medical Electronics, University of Tokyo, Japan, first reported on a 3-D ultrasound system in 1984 and succeeded in obtain- ing 3-D fetal images by processing the raw 2-D images on a mini-computer in 1986. The images obtained were processed on elaborate computer systems. This approach successfully produced 3-D images of the fetus which were nevertheless inferior to these produced on conventional 2-D scanners. At the same time, to gen- erate each 3-D image it took on an average some 10 min for data input and recon- struction, making the setup impractical for routine clinical use.
A ‘technology push’ situation further evolved when enhancement in diagnostic capabilities of scanners was propelled by the almost explosive advancements in electronic and microprocessor technology, most significantly in the 1980s and 1990s.
Part of this text was adapted from the webside www.ob-ultrasound.net, with permission of Joseph Woo, MD, Hong Kong.
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Karl Theodor Dussik (1908–1968)
Karl Theodor Dussik was born in Vienna, Austria, in January 1908. He graduated from the University of Vienna Medical School in 1931. From 1932 to 1938, he was psychiatrist and neurologist at the University of Vienna. He was later on made in charge of the clinic for diseases of the nervous system at the Allgemeine Poliklinik (General Polyclinic) in Vienna. Here, Dussik began his studies in ultrasonics dur- ing the late 1930s, working with his younger brother, the physicist Friedrich Dussik. It was a time when radar-technology was just in place and commercial metal flaw detectors had not even been invented. Ultrasound was just starting to be tested as a therapeutic tool in medicine, in European countries such as Germany and in the United States. Dussik was exploring the possibility of visual- izing intracranial structures and making ventricular measurements with ultra- sound waves. He soon became the first physician to apply ultrasound as a diag- nostic method in human subjects.
At the beginning of the Second World War, when Austria was annexed by Germany in 1938, he left the country and moved to the United States, where he worked as attending psychiatrist from 1938 to 1941 at the now defunct Metropolitan State Hospital in Waltham, Massachusetts. On returning to Austria, Dussik set up experiments at the hospital at Bad Ischl, near Vienna, to image the human brain and ventricles with ultrasound, based on a two-dimensional repre- sentation of intensity attenuation of the ultrasound through human tissues. The Dussiks presented their experiments in 1942 and after the war in 1947, introducing the term “hyperphonography”.
They used a through-transmission technique with two transducers placed on either side of the head, producing what they called “ventriculograms”, or echo im- ages of the ventricles of the brain. Coupling was obtained by immersing the upper part of the patient’s head and both transducers in a water bath, and the variations in the amount of ultrasonic power passing between the transducers were recorded photographically on photo paper as light spots. Their apparatus was quite elabo- rate with the transducers mounted on poles and railings (see below). Pulses of 1/10th second were produced at 1.2 MHz. The images produced were very rough two-dimensional images of rows of mosaic light intensity points. They had also reasoned that if imaging the ventricles was possible, then the technique was also feasible for detecting brain tumors and low-intensity ultrasonic waves could be used to visualize other internal organs of the human body.
In Dussik’s “ventriculograms” the image was thought to correspond to the shape of the lateral ventricles. These images were later thought to be artifactual by W. Güttner and others in Germany in 1952, as it was not quite possible to image the ventricles and intracranial tumors satisfactorily by such a through-transmission technique on account of the great absorption and reflection of ultrasonic waves by the skull bone. The images that Dussik obtained were found not to be true images of the cerebral ventricles.
Dussik’s work and images had led M. I. T. physician H. T. Ballantyne, physicist/engineer Richard Bolt, director of the newly established Acoustics Laboratory, and engineer Theodor Hueter from Siemens of Germany to investi- gate into similar techniques. Bolt, Ballantyne and Hueter obtained financial sup-
3.1 Über die Möglichkeit, hochfrequente mechanische Schwingungen als diagnostisches Mittel zu verwenden
port from the Public Health Service and set up a project to evaluate the value of ultrasound as a diagnostic tool in neurology.
After some initial experiments which produced results similar to that of Dussik’s, they put a skull in a water bath and showed that the ultrasonic patterns Dussik had been obtaining in vivo from the heads of selected subjects could be obtained from an empty skull.
It soon became apparent that the reflections within the skull and attenuation patterns produced by the skull were contributing to the attenuation pattern which Dussik had originally thought represented changes in acoustic transmissions through the cerebral ventricles. Further research in this area was subsequently terminated. The findings had prompted the United States Atomic Energy Commission to conclude that ultrasound had no role to play in the diagnosis of brain pathologies. Medical research in this area was apparently curtailed for the several years that followed.
After the mid-1950s, due to its ineffectiveness, the transmission technique in ultrasonic diagnosis was abandoned in medical ultrasound research throughout the world except for some centers in Japan, being replaced by the reflective tech- nique which had received much attention in a number of pioneering centers throughout Europe, Japan and the United States. Karl Dussik, despite this, must be credited for being the first medical person to have applied ultrasound as a diag- nostic tool, and in particular, in a planned and organized fashion. Douglas Gordon, a British ultrasound pioneer, in his book “Ultrasound as a diagnostic and surgical tool” published in 1964, expressly called Dussik the “Father of Ultrasonic Diagnosis”.
After the war Dussik continued to work as director at the neurology depart- ment at the Salzkammergut Private Hospital at Bad Ischl, near Vienna. In 1949 he published the neurology treatise “Zentralnervensystem und Sauerstoffmangel- Belastung” (Central nervous system and hypoxic changes).
In 1952, Dussik hosted the International Medical Ultrasonic Congress at Bad Ischl and delivered John Wild’s paper “15 Megacycle Pulsed Ultrasonic Reflection Studies on Biological Tissues” on behalf of Wild, who could not attend. Dussik moved to the United States again in 1953 and worked at the Boston Multiple Sclerosis Clinic of the Boston State Hospital and the Department of Physical Medicine and Rehabilitation of the Boston Dispensary (now the Tufts – New England Medical Center). He became involved with ultrasound used as a thera- peutic tool in physical medicine. At the first American Institute of Ultrasound in Medicine (AIUM) scientific meeting in 1953 he presented a paper on the use of ul- trasound in physical medicine and its diagnostic use in neurology. In his presenta- tion he said about ultrasonic diagnosis: “However complicated the problems may be the importance of these possibilities seems so great as to justify any and all ef- forts to overcome the technical difficulties... “. His hope and vision seem to have reached fulfilment today.
In the following year, Dussik became a member of the executive committee of the AIUM. In 1958 he published his last paper on ultrasonic diagnosis:
“Measurement of articular tissue with ultrasound” in the American Journal of Physical Medicine. He was re-elected to the Executive Board of the AIUM in 1963.
Dussik continued to practise and collaborate in research in the field of psychiatry, in particular new drug treatments for schizophrenia. This included work in the late 1960s on thiothixene with renowned Boston neuro-chemist Samuel Bogoch.
Karl Dussik passed away in Lexington, Massachusetts, USA on 19 March 1968.
In part excerpted with permission from the website www.ob-ultrasound.net by Joseph Woo, MD, Hong Kong. Picture courtesy Joseph Woo, MD.
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John Julian Wild (born 1914)
John Julian Wild was born on 11 August 1914 in Kent, England and received his ear- ly education in London. He received a BA degree from Cambridge University in 1936 and an MA degree in 1940. In 1942, he received his MD degree from Cambridge University. In 1971 Wild got his PhD from Cambridge University Faculty of Investigative Medicine.
From 1942 to 1944, Wild was a staff surgeon at Miller General, St. Charles, and North Middlesex hospitals in London. In 1944, he joined the Royal Army Medical Corps and attained the rank of major; he served in the corps until 1945. He was elected a member of the Royal Society of Medicine in 1944.
After World War II (1939–1945), Wild emigrated to the United States. Until 1951, he was a fellow in the Department of Surgery at the University of Minnesota, Minneapolis. In the spring of 1949, Wild, supported by a U.S. Public Health Service surgical fellowship, started working on bowel failure. He had previously become interested in treating bowel distension or bloating at the Miller General Hospital, Greenwich, during World War II when the condition became common, and often fatal, following bomb blast from buzz-bombs. Working with similar surgical bloating conditions in Minneapolis he needed to measure the changes in thick- ness of the bowel wall in living, distended patients in order to select the best treat- ment. For this purpose, pulse-reflective ultrasound was considered a possibility.
Furthermore he discovered differential ultrasonic properties of stomach cancer (1949).
Available commercial non-destructive testing equipment, developed by Donald Sproule in England and Firestone in the United States for detecting cracks in tank armour plate, operated at too low a frequency to achieve the theoretical resolution required for bowel wall measurement. Between 1950 and 1951, Wild’s collaboration with Lyle French at the department of neurosurgery in making diagnosis of brain tumors using ultrasound also showed that method was not very useful.
A much more sophisticated piece of ultrasonic equipment developed during wartime to train flyers to read radar maps of enemy territory lay almost idle at the World-Chamberlain Naval Air Base in Minneapolis, Minnesota. This equipment operated at 15 m/c. Wild gained access to this equipment and with the help of Donald Neal, in technical charge, quickly confirmed the possibility of measure- ment of living bowel wall thickness at 15 m/c frequency. Further experimenting with a surgical specimen of cancer of the stomach wall brought forth the then completely novel concept, by Wild, of using pulse-echo ultrasound for tumor diag- nosis and detection. This concept of the possibility of applying pulse-echo ultra- sound usefully to medicine was skeptically received by the exact disciplines.
In February 1950 Wild’s landmark paper “The use of ultrasonic pulses for the measurement of biologic tissues and the detection of tissue density changes” was published in “Surgery”. This paper was received for publication 14 November 1949 and it was the first in the literature for the discovery of ultrasonic detection of cancer growth.
More and more proof of differential sonic energy reflection by tumor-disor- ganized soft tissues was gained by subjective comparison of the graphical time- amplitude (A-mode) trace pairs obtained from control and diseased tissues. Work
3.2 Application of echo-ranging techniques
to the determination of structure of biological tissues
at the naval air base was concluded early in 1951 with examination of a clinically non-malignant nodule and a clinically malignant nodule of the living, intact hu- man breast.
These further results were published in the “Lancet” in March 1951. Wild now envisioned the exciting possibility of non-invasive ultrasonic diagnosis and even detection of early cancer at accessible sites. He had two common sites in mind, the breast and the colon. Donald Neal was soon deployed to regular naval services at the naval air base after the Korean war. In mid-1950, financed by the National Cancer Institute of the U. S. Public Health Service, Wild and John Reid, a recent graduate electrical engineer, had begun working together as an interdisciplinary team. By early 1951 they had built the first hospital “echograph” on wheels and used it at 15 m/c to gain increasing subjective clinical evidence of differential son- ic energy reflection by neoplastic tissues. Analysis of a series of clinical A-mode records of breast tumors by Wild revealed a statistically valid, objective index of sonic energy return from neoplastic tissue as compared to that of control tissue.
Real-time gross anatomical cross sectional images of Wild’s arm were obtained by application of this first self-contained small parts scanner. He produced the first two-dimensional ultrasonic (B-mode) visual images in real time of the living arm and breast tumours.This work was published in a lead article in “Science” in February 1952 (115:226–230), and preceded Howry’s first publication of laboratory images by 7 months.
Wild and Reid then built a linear B-mode instrument, a formidable technical task in those days, in order fully to visualize tumors by sweeping from side to side through breast lumps. In May 1953 this instrument produced a real-time image at 15 m/c of a 7-mm cancer of the nipple in situ, providing direct visual proof of the claimed differential sonic reflection. In 1954 Wild presented his work in a lecture at Middlesex Hospital in London, and to such notables as Prof. Mayneord at the Royal Marsden Hospital and Prof. Chassar Moir at Oxford, catalyzing work al- ready in progress. Among the audience was also Dr. Ian Donald, who later was to become one of the most important pioneers in diagnostic ultrasonography. Wild’s findings were independently confirmed in Japan in 1956 by Toshio Wagai.
By 1956, Wild and Reid had examined 117 cases of breast pathology with their linear real-time B-mode instrument and had started work on colon tumor diag- nosis and detection. Analysis of the breast series showed very promising results for pre-operative diagnosis. Most importantly, tumors at the desirable maximum size for a good prognosis (1 cm) were visualized and tumors as small as 1 mm were seen in the nipple.
In 1956 Wild also developed a rectal scanner. The transducer was inserted rec- tally, rotated, and then withdrawn in a planned scanning pattern, thus visualizing tumor of the large bowel. He also constructed a double transducer scanner for the study of the heart. A yoke holding both transducers fit over the shoulder, thus the sending and receiving transducers were placed on different sides of the chest.
Wild continued his research at the Medico-Technological Research Institute of Minneapolis, St. Louis Park, Minnesota under private funding as governmental grants were withdrawn subsequent to legal disputes.
Wild received many honors and much recognition from learned societies and universities throughout the world, including awards from the American Institute of Ultrasound in Medicine (AIUM) and the World Federation of Ultrasound in Medicine and Biology (WFUMB). Wild continued to serve as the Director of the Medico-Technological Research Institute in Minneapolis until it closed in 1999.
He was also presented the prestigious “Japan Prize” by the Science and Technology Foundation of Japan in 1991 for his pioneering work in ultrasonogra- phy. In that same year he was elected an honorary member of the Japan Society for Ultrasound in Medicine, becoming only the second foreigner to be so honored.
In 1994, Britain issued a set of stamps to commemorate Wild’s pioneer work in ultrasonography. In 1998 he was presented with the Frank Annunzio Award by the Christopher Columbus Fellowship Foundation.
In part excerpted with permission from the webside www.ob-ultrasound.net by Joseph Woo, MD, Hong Kong. Picture courtesy John Wild, MD, PhD.
John M. Reid (born 1926)
John M. Reid was born in Minneapolis, Minnesota June 26, 1926. He received his BS (1950) and MS (1957) degrees in electrical engineering from the University of Minnesota, and the PhD in Electrical Engineering from the University of Pennsylvania (1965). From 1950–1957, Reid worked on medical diagnosis with ul- trasound at the Department of Electrical Engineering and Surgery, University of Minnesota and St. Barnabas Hospital, Minneapolis, where he worked on tissue characterization with ultrasound and developed the first clinical ultrasonic scan- ner with John J. Wild.
Reid was engaged through a grant from the National Cancer Institute as the sole engineer to build and operate Wild’s ultrasonic apparatus. Wild and Reid built, amongst other ultrasonic devices, a linear B-mode instrument, a formidable technical task In those days, in order fully to visualize tumors by sweeping from side to side through breast lumps. In May 1953 this instrument produced a real- time image at 15 m/c of a 7-mm cancer of the nipple in situ along with A-mode dif- ferential sonic reflections. Based on technology from the World War II radar, Reid devised important circuitry to compensate for the attenuation of ultrasound in tissues by setting the receiver gain as a function of the tissue depth. Similar mech- anisms were deployed in most medical ultrasound systems that followed.
In 1957 Reid completed his MS thesis, which compared the theory for focusing radiators to experimental findings. In addition he had importantly verified that dynamic focusing was practical. He subsequently left Wild’s laboratory and pur- sued his doctoral degree at the Department of Biomedical Electronic Engineering, Moore School of Electrical Engineering, University of Pennsylvania, Philadelphia.
From 1957-1965 he worked on echocardiography, producing and using the first such system in the United States, with cardiologist Dr. Claude Joyner. This re- quired developing design and construction methods for making ceramic pulse- echo transducers and measuring their performance. Reid was responsible for con- structing Joyner’s equipment, which could display both the EKG and echocardio- gram simultaneously. He also worked out methods for measuring the ultrasonic power levels used by diagnostic machines using a radiation force balance, and de- veloped methods for making ultrasonic scattering measurements in tissues.
Reid became a Research Assistant Professor at the Department of Physiology and Biophysics (1966–1968) and the Center for Bioengineering (1968–1977) at the University of Washington, Seattle. Here he continued the tissue research, which culminated in measurement of the scattering cross section of red blood cells, with Professor Rubens Sigelman and Dr. K. Shung. In addition, he worked on the con- tinuous wave and pulse Doppler and duplex imaging devices with the Donald Baker team. He participated in forming the Institute of Applied Physiology and Medicine in Seattle with Dr. Merrill Spencer, and also was affiliated with the Providence Hospital from 1971-1981, while working on measurements, gas bubble detection, Doppler imaging and other ultrasonic developments.
He also participated in the standards writing work of the International Electrotechnical Commission, as a United States delegate to their ultrasonics sub-
committees and working groups since 1981, funded by the National Electrical Manufacturers Association and the American Institute of Ultrasound in Medicine.
In 1981 Reid held the Calhoun Chair of Biomedical Engineering at Drexel University and became an Adjunct Professor of Radiology at Thomas Jefferson University, both in Philadelphia, where the work on ultrasonic diagnosis of tissue has continued to date. This is a Program Project funded by an NIH grant and in- volves nine projects with other professors at Drexel and Thomas Jefferson. He was Acting Director of the Biomedical Engineering and Science Institute at Drexel University for two years, and although retired from the Calhoun Chair in 1994, is currently an Emeritus and Research Professor at Drexel, a Professor of Radiology at Thomas Jefferson University and an Affiliate Professor of Bioengineering at the University of Washington. His current activities include directing an N.I.H.
Program Project grant with other faculty members at Drexel and Thomas Jefferson Hospital on diagnosis of human breast cancer using ultrasound, consult- ing and writing on medical ultrasound systems and transducers. He is also in- volved in the investigation of the propagation and scattering of ultrasound waves in biological tissues (tissue characterization), and the study of cardiovascular sys- tem structure and function through the ultrasound Doppler effect.
Professor Reid is a Life Fellow of the IEEE, a Fellow of the Acoustical Society of America and of the American Institute of Ultrasound in Medicine, whose Pioneer Award he received in 1979, and of the American Institute for Medical and Biological Engineering. He received the Career Achievement Award of the IEEE Engineering in Medicine and Biology Society in 1993 and the Pioneer Award of the Society of Vascular Technologists in 1994. A special issue of the journal
“Ultrasound in Medicine and Biology” dedicated to him and containing papers by his students and collaborators was published in 1994. In 2000, Professor Reid was elected Honorary Member of the World Federation for Ultrasound in Medicine and Biology.
In part excerpted with permission from the webside www.ob-ultrasound.net by Joseph Woo, MD, Hong Kong. Picture courtesy John Reid, PhD.
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Inge Edler (1911–2001)
Inge Edler was born on 17 March 1911, in Burlöv, Malmöhus County, Sweden. His parents were Carl and Sophia, who were teachers in the primary school in that vicinity. He graduated from the local high school, Högre Allmänna Läroverket, in 1930. Young Edler wanted to continue with university studies in physics, particu- larly micronics, but he was convinced by his sister to go for dentistry instead. As it was too late to enroll in the faculty of dentistry, he was able to be accepted by the faculty of medicine at Lund University. This was supposed to be a stopgap meas- ure. However, medicine intrigued him so that he continued his studies at the uni- versity, receiving his medical degree in 1943.
Dr. Edler’s professional career was initiated in the field of general medical prac- tice, but was soon restricted to his employment in the Department of Internal Medicine at the University Hospital of Lund, and in the space of several years re- volved primarily around cardiology. He was appointed director of the Laboratory for Heart Catheterization at the University Hospital in 1948 and functioned in this capacity until 1950. At that time, he was appointed director of the Department of Internal Medicine and the Cardiovascular Laboratory at the University Hospital, Lund. He remained in this capacity until 1960, assuming additional administrative duties in 1953 as Head of the Department of Cardiology until his retirement in 1977. In this position he was responsible for the preoperative diagnosis of heart disease. At that time, cardiac catheterization and contrast X-rays of the heart failed to give enough data for a correct appraisal of the status of the mitral valve.
Since a correct diagnosis is of great importance before an operation, Edler felt strongly the inadequacy of the existing methods. This concern caused him to look for a new non-invasive alternative, which he thought might resemble some kind of radar.
At the same time in the early 1950s Carl Hellmuth Hertz, the son of the famed Nobel Laureate Gustav Hertz, was working as a graduate student at the nuclear physics department of the University of Lund. Because of this interest, he also studied ultrasound. He was acquainted with the ultrasonic reflectoscope devel- oped for non-destructive materials testing. An ultrasonic reflectoscope was bor- rowed from the Tekniska Rontgen-Centralen, a company in the nearby town of Malmo, which specialized in non-destructive testing. With the equipment, they were able to obtained well-defined echoes on the CRT screen moving synchro- nously with his heart beat. Since Hertz’s father had been the director of the Siemens Research Laboratory before the end of the war, they were able to contact director Wolfgang Gellinek of the Siemens Medical Branch in Erlangen, Germany, to borrow one of their Siemens reflectoscopes. Edler and Hertz received the reflec- toscope in October 1953 and set to work on it immediately.
In 1953, the first ultrasound heart examination in the world was performed in Lund. Edler finally established the characteristic motion pattern for the anterior leaflet of the mitral valve. He compared the shape of the fast-moving echoes in pa- tients with enlarged hearts due to mitral stenosis during cardiac operations, and found empirically the shape correlated well with the severity of the stenosis.
By early 1955, Edler had so much evidence of this relationship that he relied on ultrasound alone for the diagnosis of mitral stenosis. The typical motion patterns
3.3 The use of ultrasonic Reflectoscope for the continuous recording of the movements of heart walls
of other heart valves, pericarditis, tumors, and thrombosis in the left atrium showed up in their recordings and were identified by close cooperation with Dr.
Olle Dahlback’s heart surgery group. The advent of a barium titanate transducer produced by Siemens in Germany in 1958 was an important advance for the group and enabled them to study not only the normal mitral valve but also many other heart structures.
Edler was active as a member of many societies devoted, in whole or in part, to the advancement of ultrasound. Among them were the American Institute of Ultrasound in Medicine, Deutche Gesellschaft für Ultraschall Diagnostik in der Medizin, the Swedish Society of Medical Ultrasound, the Yugoslav Association of Societies for Ultrasound in Medicine and Biology, the Swedish Society of Cardiology, and the American College of Cardiology.
Throughout his professional career, Dr. Edler was awarded many honors. The Albert and Mary Lasker Foundation awarded him and Hellmuth Hertz the Clinical Medicine Research Prize in 1977 for pioneering the clinical application of ultrasound in the medical diagnosis of abnormalities of the heart. This was fol- lowed in 1983 by the Rotterdam Echocardiography Award for his outstanding and pioneering work applying ultrasound as a diagnostic tool in cardiology. In December 1984, he received the Lund Award for “scientific work of extraordinary significance” from the Royal Physiologic Society. In 1987, Lund University be- stowed upon him the title of Professor H.C. One year later he was again honoured with the Münchener and Aachener Preis für Technik und angewandte Naturwissenschaft, and finally, in 1991, he was awarded the Eric K. Fernströms Stora Nordiska Pris
Inge Edler died on 7 March 2001, just 10 days short of his 90th birthday.
Information and picture courtesy Lars Edler, MD.
Carl Hellmuth Hertz (1920–1990)
Carl Hellmuth Hertz was born in 1920 as the son of a very prominent father, and Nobel Prize laureate Gustav Hertz. Early in 1950 Hellmuth Hertz began research on ultrasound in medical examinations, thereby becoming known throughout the world. A Swedish physician, Inge Edler, told Hertz that he wanted to devise a non- invasive method for examining the heart. Echocardiography has revolutionized cardiovascular diagnostics.
Since Hertz’s father had been the director of the Siemens Research Laboratory before the end of the war, they were able to contact director Wolfgang Gellinek of the Siemens Medical Branch in Erlangen, Germany, to borrow one of their Siemens reflectoscopes. Edler and Hertz received the reflectoscope in October 1953 and set to work on it immediately.
In 1977 Hertz and Edler received the American equivalent of the Nobel Prize in medicine, the Lasker Prize. The use of ultrasound in medical diagnostics is in- creasing sharply in a number of different fields.
Carl Hellmuth Hertz became founding professor of the Department of Electrical Measurements, Lund Institute of Technology at Lund University.
Hellmuth Hertz received several prizes, from the Westrupska Prize in 1963 for his work in biophysiology of plants to the Lasker Prize for medical ultrasound in 1977 together with Inge Edler. Many other prizes and accolades followed.
The activities in the field of ultrasound created a demand for some kind of printer suitable for the printing of color pictures. This brought the beginning of a new activity. Hertz invented ink-jet printing, a method for the electrical control of tiny droplets, which enabled him to put a dot of ink on a piece of paper in about
one-millionth of a second. The pixel size was 0.1 x 0.1 mm with continuously vari- able color saturation in each pixel. The first steps in ink-jet printing were taken during the sixties. The common mingograph – a multi-channel ink-jet printer – designed by Elmquist and in common use at hospitals for registration of ECG came to serve as the basic instrument on which the first experiments were made.
The original goal was that the ink-jet plotter would replace the conventional film for printout of medical images, such as X-rays, CT and ultrasound images, for use in the future “digital” hospital!
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