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The Development of Medical Device : X- Ray Belinda Pingguan, Juliana Basheer Biomedical Engineering Program, University Of Malaya CONTENTS Conception of Ideas Invention Process and Clinical Prototyping Refinement and Enhancement Outcome Limitation CONTENTS Conception of Ideas Invention Process and Clinical Prototyping Refinement and Enhancement Outcome Limitation Conception of Ideas X-rays were accidentally discovered by Dr.Willem Roentgen in late 1895, in Wurtzburg, Germany. Dr Williem Roentgen Conceptions of Ideas-cont Roentgen was carrying out experiments with a Crookes tube, a fairly common research apparatus of the time. As Roentgen applied large voltages to the device to study the behaviour of electrons emitted from the metal, he noticed that a piece of phosphorus material, situated elsewhere in the room, glowed! Conception of Ideas-cont He tried to block the emissions by covering the tube first by a piece of cardboard and then by a piece of wood only to find that the phosphorus still glowed. He also noticed that when he held his hand between the tube and the phosphorus, the light given off seemed to present an image of his hand. Conception of Ideas-cont To convince himself he wasn't going crazy, Roentgen recorded such images on pieces of film thus obtaining the first x-ray images of human anatomy. Mrs. Roentgen’s hand- the very first xray of human CONTENTS Conception of Ideas Invention Process and Clinical Prototyping Refinement and Enhancement Outcome Limitation Invention Process and Clinical Prototyping Simons was the first to start to design x-ray tube This tube is equipped with a disk-shaped cathode of molybdenum and a magnesium target. It is evacuated to a barometric pressure of .0001 millimeters of mercury. The over-all length of the tube is about seven X-ray tube designed and constructed inches. by Simons Invention Process and Clinical Prototyping Circuit diagram of Simon's Xray apparatus Invention Process and Clinical Prototyping The source of high voltage for Simon's X-ray machine CONTENTS Conception of Ideas Invention Process and Clinical Prototyping Refinement and Enhancement Outcome Limitation Refinement and Enhancement Currently most diagnostic (such as chest and mammographic i.e. breast imaging) radiographic systems in clinical use are based on a phosphor screen. Phosphor screen emits light in response to x-rays absorption. The resulting optical image is conventionally used to expose a photographic film as shown above. This method is referred to as film-screen radiography and has been used since the discovery of x-rays 100 years ago. Digital Radiography In recent years there has been considerable research effort in finding digital alternatives to filmscreen radiography. Digital x-ray imaging refers to methods in which the image information is represented as a matrix of numbers whose value corresponds to the x-ray transmission. Digital Radiography-cont In general, a digital detector would absorb x-rays and produce an electric signal, either directly or indirectly via multiple stages, as the output. The electric signal can then be assigned numerical, i.e. digital, values according to its amplitude and these numbers can be stored in an 2-dimensional array to be displayed as an image on the computer screen. Digital Radiography-cont Once in digital format images can be stored and transferred as data files. Digital imaging would potentially also allow improved image quality In addition, digital images can be displayed on a computer monitor, their appearance can be altered via image processing and computer software can be use to aid disease diagnosis. An example of digital radiography Fluoroscopy refers to real-time imaging carried out to observe motion within the body. Procedures where fluoroscopy is used include the barium swallow and the barium enema carried out to study the intestine. Flouroscopy II of Flouroscopy Fluroscopy - Cont Fluoroscopic imaging of the blood vessels, angiography, involves a contrast agent injected into the vessel to increase its x-ray absorption and thus its contrast in the x-ray image. Computed Tomography Scanner Newer non-invasive perspectives in CT imaging e.g. angiography of aorta/arteries in midbrain with an excellent vascular enhancement due to bright vascular opacification. Computed Tomography -cont Ct Scanner also provide premier image quality for quicker diagnosis. The most patient friendly CT scanning technique available (entire liver or lung exam in single breath-hold). It also provide maximum patient comfort due to minimum scanning time and low Xray radiation for patient safety. Mammography Mammography is a radiographic examination specially designed for detecting breast pathology. Recent interest in breast imaging has be fostered by the realization that approximately 1 out of 9 women will develop breast cancer over a lifetime. Early x-ray mammography was done with nonscreen, direct exposure film. These images exhibited low contrast , required high radiation doses and yielded poor diagnostic quality. Mammography-cont The new version optimises X-ray dose and image quality.Determines the optimum degree of compression needed to produce uniform tautness, based on individual breast characteristics. Stereotactic biopsy are also attachment with the advancement. It also provide maximum patient comfort and low scanning time. CONTENTS Conception of Ideas Invention Process and Clinical Prototyping Refinement and Enhancement Outcome Limitation Outcome Limitation Much work has been done to optimize film-screen radiography, but it still has shortcomings in image quality, dose efficiency as well as practicality. Many of these limitations arise from the fact that the film is used both as x-ray detection, and image recording and storage medium. Thank You for Your Attention