Hounsfield (Hounsfield), Godfrey

genus. August 28, 1919
English physicist Godfrey Newbold Hounsfield was born in Newark (Nottinghamshire County). , His father, Thomas Hounsfield, worked as an engineer in a steel mill, but after the First World War, he bought a small farm in Nottinghamshire. As the youngest of five children, Godfrey rarely participated in the games brothers and sisters, so he spent much time on the farm, turning it into a playground. Being constantly surrounded by farm machinery, he happily studied her work, from the children's enthusiasm has arisen a tendency to engineering. As a youth, Godfrey was able to design a glider that is launched from the roof of the barn, a fountain, a pump which is powered by acetylene engine, as well as the gramophone and radio.
In grammar school, Newark Liberty X. interested mainly in physics and mathematics. In 1939, Mr.. He took a course at City College Guild in London, and at the beginning of the Second World War he was conscripted into the Royal Air Force and served as an instructor in radar technology at Imperial College in South Kensington. Simultaneously X. lectured at the Air Force School Krenvella radar, which constructed widescreen oscilloscope and other teaching aids. In 1945, Mr.. he noted a special award for his services during the war, and the following year he was discharged.
A year after the dismissal X. the grant was approved, which allowed him to enter the Electrical Engineering College of Faraday in London. After his graduation in 1951. He began working for the company EMI, conducted the research in the field of electronics for commercial use. While serving in the Air Force, dealing with radars and tracking systems for aircraft objects, X. interested in electronic computers. In 1958 ... 1959. group of specialists, to which he belongs, it was possible to construct the first in England inpatient transistor computer. Early transistor computers did not have special advantages in comparison with lamp. H. managed to increase their speed and power at the expense of his system, based, as he himself said, on the management of transistors using magnetic fields.
In the early 60-ies. H. worked in a number of head of research laboratories EMI to develop thin-film technology to increase the amount of memory in computers EMI, but it was abandoned for reasons of commercial unprofitability. H. also participated in the creation of computer programs in the identification. These experiments led him to the idea to develop a computer that could determine the degree of x-ray absorption in biological tissues and thus more fully use their capabilities.
. Medical radiology as a science emerged in the late XIX century. When Wilhelm Roentgen discovered the rays which he called the X-rays, receiving help with their first images of various objects
. In typical X-ray image X-rays pass through the investigated part of the body and pass through the X-ray film. Since the bone absorb more energy X-rays than soft tissue, less dense bones look at the film as shown by light areas, called shadows. Soft tissue, overlapping, outlines poorly. Consequently, the distinction between normal and altered soft tissue (eg, tumor) with conventional radiography is not possible.
Allan Cormack, a specialist in medical physics from Tufts University (Massachusetts), with which X. I was unaware, in the late 50's - early 60-ies. developed a mathematical method for determining the x-ray absorption in biological tissues. Cormac method based on multiple measurements of the absorption of a thin X-ray beam passing through the body at different angles, making it possible to obtain a thin cross section. Since the beam probed a certain area with many points, obtained information shows the absorption characteristics of each individual part of this site. The normal X-rays determined only by the total absorption of the beam reaching the film. Images of tissues lying along the beam, with the 'overlap' each other.
Method Cormac allowed to recreate an image of internal parts of the body structure on the basis of different absorption of X-rays. Work Cormac though it was published, but did not attract the attention of the scientific community, and his method remained primitive laboratory method of studying simulated situations rather than biological tissues. In addition, high-speed computers.
. capable of performing a large number of mathematical operations per second required for the analysis of the results have not yet been established, so the method of Cormack was laborious, time-consuming
. Obtaining X-ray images of slices of the body was called imaging, from the Greek tomos, meaning 'cut'. Gradually, with the development and availability of high-speed computers, the method became known as computerized axial tomography (CAT) or CAT-scan, also known as computed tomography (CT) or CT-scan.
In 1967. H. regardless of Cormac began to work on his CAT-system, starting with gamma-rays, as Cormack, and developed a scheme very similar to the scheme of Cormac. For gamma-rays remain the same principle as for X. H. developed a somewhat different mathematical model, using a large computer for processing data, and through its engineering cast of mind has introduced tomographic method of research in practice.
. First, the time required to scan the object, was 9 days, which was associated with low-intensity source of gamma-rays, requiring prolonged exposure
. Powerful X-ray tube reduces the time the study up to 9 hours. Successful images were obtained during examination of the human brain, the brain of a living calf and pig kidney area. Contrast images obtained were very clear and made it possible to assess brain tissue and other organs, but there was no certainty that this method will provide an opportunity to distinguish the affected tissues from normal, for example, to identify tumor. To achieve this goal in 1971. Atkinson Morley Hospital in Wimbledon was designed and installed fast and complicated apparatus, the first clinical CAT scanner. In 1972. was made by first scanning image of the brain, women with suspected his defeat, and the resulting image clearly showed the presence of dark circular cyst. Were gradually assembled a large and fast scanners, which have reduced scanning time to the first 18 seconds, and then to 3 seconds or less, giving the images of various organs with high resolution.
X. described the creation of NAT devices in the collection of the annual conferences of the British Institute in London and in December 1973. wrote an article entitled "Computerized transverse axial scanning: CT '(' Computerized Fransverse Axial Scanning: tomography '), which cited the results of clinical studies using the first EMI CT scanner serial 1000. Immediately it became apparent that the use of CAT represents significant progress compared with other methods of obtaining images of biological tissues. This method provides details of the structure of soft tissues, . previously inaccessible to study, he admitted with greater accuracy to detect such changes, . as tumor, . and made it possible to accurately measure the absorption of X-rays by different tissues, . which proved to be valuable for diagnosis and treatment,
. H. calculated that the CAT scan hundreds of times more effective than conventional X-ray studies, because it uses all the information, whereas the first fix only one of its percentage. In addition, the scanner is more sensitive and requires less energy X-rays on a single frame than a standard X-ray equipment, although the total exposure they have approximately the same, t. to. Scanning requires multiple exposure.
. Industrial CAT scanner consists of a source of X-ray scanning device containing an X-ray tube, detector, computer data-processing terminal and printer to record costed image
. Scanner is moved around the head or body, producing up to a million individual measurements of attenuation of the beam at different angles. (In some devices detectors fixed motionless, while rotating only one X-ray source.) Of this colossal amount of information a computer recreates the cross sections of the investigated parts of the body. During the procedure the patient is moved along the longitudinal axis of the frame scanner. As a result of processing a series of consecutive transverse slices reconstructed spatial image makers.
In 1972. H. was appointed head of the department of health systems in EMI, and in 1976. a leading researcher of this company. Since 1978, Mr.. he - a member of scientific societies in the University of Manchester.
X. and Cormac was awarded the Nobel Prize in Physiology or Medicine 1979. 'for the development of computerized tomography'. Speaking about the development of computerized axial tomography in the Nobel lecture, X. explained that the 'method of reconstruction of the image is developed as a result of the practical steps. Most of the mathematical methods available at that time was of abstract and was of little use for practical use '.
Follow-up X. based on further improvement of technology and CAT are close to her diagnostic techniques, such as nuclear magnetic resonance, a recently developed method for obtaining the image does not use X-rays.
X. life was a bachelor. He loved long walks, 'badinage on abstract themes', played on the piano. Biology has never attracted his attention, he once again carried away by physics.
Among the many awards X. - Award-Robert Mak Society of Mechanical Engineers (1972), . Prize Barkla British Institute of Radiology (1974), . Albert Lasker Award for basic medical research (1975), . Medal and Prize Daddela Institute of Physics (1976), . Prize of the International Society of Gardner (1976),
. He received an Honorary Doctorate of Basel and the University of London. H. - Honorary Member of the Royal College of Physicians and the Royal College of Radiologists.