NOTE: Free essay sample provided on this page should be used for references or sample purposes only. The sample essay is available to anyone, so any direct quoting without mentioning the source will be considered plagiarism by schools, colleges and universities that use plagiarism detection software. To get a completely brand-new, plagiarism-free essay, please use our essay writing service.
One click instant price quote
... the systems at the development and design stages) fall under classification as follows: The systems that digitize X-ray image retrieved with the help of X-ray image amplifier (for example, the mass-screening units based on image intensifier); CR - Digital X-ray imaging implying luminophors and fluorescent (for example, computed radiography digitizers). This type of radiography systems utilizes phosphor plates. Semiconductor detectors; Digital X-ray imaging on the basis of multi conduct proportional camera; Digital X-ray imaging on the basis of multiple camera technology; The systems that use digital scanning for posterior development and processing digital x-ray images (for example, scanning radiographic X-ray units). There are three popular systems of digital X-ray imaging: CR (computed radiography), DR (digital radiography), and CCD (charge-coupled device) Array.
The successful candidate should show a profound knowledge of these systems along with the understanding of the mechanisms of their functioning. So, lets examine these systems more thoroughly. CR Computed Radiography Systems CR systems utilize luminescent storage screens. CR systems allow the radiologist to make digital X-ray images using any kind of X-ray units utilized in analogue radiology (even in resuscitators and resuscitation units). The main features of CR systems are: Possibility to choose the area of radiation sensor (detector); Wide dynamic range that allows receiving high quality images (both hard and soft tissues); The sensitivity is close to the film speed; Allows creating digital archive; Networking; Computed Radiography is the most popular method of digital X-ray imaging. For example, in osteology CR allows making digital image of bone and tissue structure, soft tissues, junctions, tendons, muscles, subcutaneous fat, and skin.
The analogue radiography is unable to provide the X-ray image of similar quality. So, how does computed radiography works? Computed radiography system utilize special plates that receive the image after they are irradiated (successively, dot by dot) scanned by special laser device. The luminous flux that appears in result of this irradiation is transformed into digital signal. After the computer enhancement is completed, the contours of the image are intensified, and image visibility is enhanced, the digital image is either being printed (film printing) or reproduced at the television monitor of the working console.
Luminous plates- storage elements can be placed instead of the traditional sets film screen-intensifier and may be used in traditional X-ray units. The luminous place has higher exposure latitude compared to traditional combinations film-screen. This feature allows increasing the interval between under- and over-exposure. In such a way, computed radiography allows to obtain comparatively contrast digital images even in case the exposure share is very low (when the lower limit is equal to the level of quantum noise).
Therefore, even in case the X-ray imaging is made in the patients room, digital luminous technology guarantees qualitative X-ray image. Digital luminous technology utilizes digitizers with high level of spatial resolution (compared to traditional screen-film technologies). Yet, the main advantage of digital luminous technology is the ability to reproduce low-contrast details, while the exposure of small and tiny details remains the prerogative of traditional X-ray imaging (film imaging). The basic structure and methods of functioning can be presented with the help of the following image: Image 1 - Computed radiography digitizer 1 Generator; 2 - X-ray tube; 3 patient; 4 storage plate; 5 transporting device; 6 - analog-to-digital converter; 7 image storage device; 8 - video processor; 9 network; 10 digital-to-analog converter; 11 monitor; 12 X-ray image; 13 radiologist What concerns pneumo genic pathologies, computed radiography allows finding out mutative change of low and high density. It makes possible to differentiate the nidus of infection and pulmonary fibrosis from infiltrating tumors (Siegel 82).
Anatomical elements of root of lung and pulmonary pleura are visible thus making possible to find out lysis of cells. Computed radiology is effectively applied in urology, as it provides an opportunity to obtain the shadows of insignificant radiopaque calculus in the areas, where visualization causes certain difficulties of diagnosis (when traditional x-ray imaging is used). Digital X-ray imaging allows visualizing more distinguished boundaries and shadows of kidney at the plain films, along with contours of soft tissues and muscles. High contrast resolution and wide dynamic range of digital x-ray imaging characterize distinctive features and peculiarities of visualization of stomach, small and large intestines pathologies.
Computed Radiography combines the basic methodological settings of analogue x-ray examination (spot-film radiography, dosing irradiation, etc) (Dreyer 115) with all digital technologies. The importance of use of computed radiography in child pathologies should not be underestimated, as it implies the lowest level of irradiation and qualitative X-ray inspection. The advantages of computed radiography systems for making digital X-ray images in resuscitation units with the help of palate myo graphs and other medical equipment should be taken into account. Digital Radiography and electro optical transducer (image converter tube) screen Digital Radiography system consists of image converter tube, television tract with high resolution, X-ray high-voltage generator, and X-ray emitter, digital converter, and other components. During the traditional X-ray imaging, optical image that appears in the transmitters output screen, the image is captured by 100 mm photo camera or cinerama (Fujita 13 - 18). Digital X-ray imaging is completely different, as the signal coming from camera is transformed by analog-to-digital converter into digital data set, and then it is transmitted into storage device.
Later, the obtained data, in accordance with the selected parameters, are transformed into visible image by computer device (See Image 2) Image 2 Digital Radiography 1 Generator; 2 - X-ray tube; 3 patient; 4 - electro optical transducer (image converter tube); 5 camera; 6 - analog-to-digital converter; 7 storage device; 8 video processor; 9 network; 10 digital-to-analog converter; 11 monitor; 12 X-ray image; 13 radiologist Selenium Photocell-based Radiography Selenium Photocell-based Radiography is one of the newest digital radiography systems. The basic part of this system consists of detector in the form of drum covered with a layer of amorphous selenium (See Image 3). Image 3 - Selenium Photocell-based Radiography 1 Generator; 2 - X-ray tube; 3 patient; 4 Selenium drum transducer; 5 scanning electrodes and amplifier; 6 - analog-to-digital converter; 7 image storage device; 8 video processor; 9 network; 10 digital-to-analog converter; 11 monitor; 12 X-ray image; 13 radiologist Selenium radiography is used in the systems of chest X-ray imaging alone. High contrast between lung fields and mediastinal pleura peculiar for chest X-ray images is smoothed out during digital processing (Hoehne 602 - 623).
At the same time, this new technology doesnt reduce the hardness of the digital image. High ratio signal / noise is the second advantage of Selenium-based radiography. Charge Coupled Device (CCD) Array CCD is also one of the most popular digital X-ray imaging systems. The history of CCD springs from 1963 (Trussell 615 - 627), when S. R.
Morrison (Honeywell Co. ) announced the invention of photo scanner semiconductor photosensitive device. Later in 1970, due to extensive studies and researchers conducted by W. S. Boyle, G. E. Smith and G.
G. Amelia (Bell Laboratory) (Trussell 615 - 627) Charge Coupled Device appeared. So, what is the technology used in CCD? The following image explains the principle of operation on the basis of the simplest CCD. It provides a schematic map describing one pixel in the mode of storage.
The structure consists of p-type siliceous support, isolating layer silicon dioxide, and electrodes. Charge Coupled Device principle of operation is based on inner photo emissive effect. The modern CCD matrix use additional thin n-layer (so-called volumetric al transport channel) that allows reducing the negative impact caused by near-surface layer of the semiconductor (Trussell 615 - 627) and adds sharpness to the image. Besides, some manufacturers use anti blooming technology to prevent the effect of charge spread caused by intense irradiance. Radiologist: Qualification and Skills First of all, radiologist should understand the process of X-ray imaging and digital x-ray imaging perfectly.
The successful candidate should understand that radiology and X-ray imaging is not just a method that allows finding out diseases, but also one of the most valuable methods that makes the radiologist to understand and examine the (pathologic) process through the various intermediate stages. The very term radiology seems to be too narrow, as it is unable to explain the wide range of qualifications and skills required by radiologist during his career. From the above it appears that the successful candidate should be able to meet the exacting needs and high requirements. To a certain extent, radiologist is a consultant, who has to be familiar with the state-of-the-art technologies. It is our opinion that radiologist should be an active participant not only in the issues concerning the questions of x-ray image recognition, x-ray imaging, or examination. The successful candidate should also know how to use the technologies and particular features of digital X-ray imaging in order to have a comprehensive and all-out picture of clinical understanding of his actions.
Under this assumption, the qualified radiologist, who is responsible for diagnosis of bones and junctions malfunctions and diseases, should bring himself abreast of the trends of radiology. He should also keep himself abreast of the basic modern knowledge in etiology and pathogenesis of diseases, to know their clinical manifestation and symptoms, the existing methods of treatment, indications and contraindications for use, to mention a few. A successful candidate should also be able to evaluate the clinical course under the influence of medical treatment, scientific prognostics, etc. It means that, for example, a successful radiologist, who specializes in the field of clinical osteology should have definite knowledge in related areas (e. g. surgery, orthopedics, traumatic surgery, astrology, oncology, medial medicine, pediatrics, neuropathology, phthisiology, syphilology, infectiology, hematology, endocrinology, vitamin ology, toxicology, military medicine, to mention a few).
Naturally, it doesnt mean that the radiologist should know all these medicine-related areas perfectly, but he should have at least general knowledge in all these areas. The successful candidate should have certain knowledge in general medicine, along with the knowledge enough to have his own representation of complicated clinical presentation. In case the radiologist has knowledge enough, he will be able to persist in his stand (in case necessary, and/ or in case of disputable diagnosis). In case the candidate is unable to meet these requirements, he will be unable to fulfill his duties perfectly.
No doubts, the final product of X-ray examination is the x-ray imaging and the conclusion made by radiologist. X-ray film itself is very important, but radiologists conclusion is the matter of primary importance. The X-ray imaging itself is the first step on the way to correct medical diagnosis. It requires specific technical skills and experience. At the same time, technological aspects of x-ray imaging are rather the matter of secondary importance. The most qualitative x-ray image cannot provide an appropriate interpretation itself.
Therefore, the successful candidate should understand that the most responsible moment of the radiologists work is interpretation, and the ability to read x-ray image. Here we come to conclusion that the successful candidate should combine technical skills with his practical experience and knowledge. Works Cited Andriole, K. "Workflow assessment of digital versus computed radiography and screen-film in the outpatient environment. " Digital Imaging Journal 15. 1 (2002): 124 - 127. Belikova, T. "Digital image processing in radiology: An experience of development of technology for computer-aided diagnosis. " CAIP (1993): 614 - 626.
Dreyer, K. PACS-A guide to the digital revolution. New York: Springer-Verlag, 2002. Fujita, H. "Investigation of basic imaging properties in digital radiography. 5. Characteristic curves of I. I. -TV digital systems. " Medical Physics 13 (1986): 13 - 18.
Hoehne, K. "Processing and Analysis of Radiographic Image Sequences. " ISPDSA 83 (1991): 602 - 623. Luo, J. "Automatic Detection of Radiation Fields in Digital Radiographic Images. " PRAI 13. 1 (1999): 149. Siegel, E. Filmless radiology. New York: Springer-Verlag, 1999.
Trussell, H. J. "Processing of X-Ray Images. " PIEEE 69. 5 (1981): 615 - 627.
Free research essays on topics related to: technical skills, x ray, soft tissues, ray, digital image
Research essay sample on X Ray Soft Tissues