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RADIOLOGY NEXT GENERATION SCIENCE / COMMON CORE STANDARDS ADDRESSED! • CCSS.ELA-Literacy.RST.11-12.2 Determine the central ideas or conclusions of a text; summarize complex concepts, processes, or information presented in a text by para CCSS.ELA-Literacy. • RST.11-12.3 Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks; analyze the specific results based on explanations in the text phrasing them in simpler but still accurate terms. AGRICULTURE, FOOD, AND NATURAL RESOURCE STANDARDS ADDRESSED • AS.07.01. Design programs to prevent animal diseases, parasites and other disorders and ensure animal welfare. • AS.07.01.01.a. Identify and summarize specific tools and technology used in animal health management. BELL WORK • Describe the safety precautions that should be observed when performing an x-ray. • How should lead gloves and aprons be stored? • Describe the steps for determining the machine settings for a radiograph. • What is a grid and what is its purpose. TERMS! • Anterior • Computerized Axial Tomography • Computerized Tomography • Digital Radiography • Dorsal • Magnetic Resonance Imaging • Posterior • Ultrasound • Vacuum Tube • Ventral INTRODUCTION • Veterinarians view radiographic imaging as their most important diagnostic tool. • The veterinary assistant generally serves a role in the radiographic process. • The Vet Assistant must understand terms, equipment and the process in producing quality images. • The radiographic process continues to improve with techniques such as computer enhancement becoming common place. • The better the image quality, the easier the diagnosis. X – RAY PRODUCTION • An x-ray tube is a vacuum tube containing a metal target onto which a beam of electrons is directed at high energy for the production of x-rays. • The vacuum tube has an emitter which establishes a flow of electrical current know as a beam. • A high power electrical power source accelerates the electrons. • The electrical flow collides with a target. KILOVOLTAGE PEAK • Kilovoltage peak (kVp) refers to the maximum value of the applies x-ray tube voltage during x ray production. • The following variables will impact the x-ray signal; • • • • • Penetrability Number of x-ray photons produced Frequency Energy Wavelength • Radiation will change as it pass through tissue with some radiation absorbed by soft tissue. These changes may affect the image. • Increasing the kVp increases the number o photons produced and increases the penetration of the x-ray. This could lead to black x rays. • Decreasing the kVp causes fewer photons to reach the target and yields x rays that appear to be under – exposed to light. • Always remember to adjust beam intensity as you move closer for further away from the patient. • Generally most small animal images are taken at 40 inches. Decreasing the distance will reduce the patients exposure to radiation. • X ray scatter control is very important. Filtration and collimation devices area installed on x ray housing to decrease exposure to scatter radiation. X RAY GRID • The purpose of the x ray grid is to eliminate scattered radiation from hitting the image receptor. • The x ray grid is a filtering unit made primarily of lead and strips of radiolucent materials. • X ray beam intensity may be adjusted according to the grid size. DETERMINING MACHINE SETTINGS • X ray technique chart. RADIOGRAPHIC POSITIONS • Generally x rays are taken from at least two views. • The vet. Assistant needs to be familiar with normal positions used for radiography. Generally the second x ray will be at a 90 degree angle from the first image. • Normal views used; • • • • Dorsal – top Ventral – lower Anterior – front Posterior – rear • Lateral always refers to an outer view while medial refers to an inner view. METHODS OF IMAGING • Imaging in modern veterinary clinics is not limited to x-ray alone, numerous other imaging processes are now available to todays generation of veterinarians. Computerized Axial Tomography – CAT scan – computerized 3D images Magnetic Resonance Imaging – MRI- magnetic field and radio wave create images Ultrasound – Uses high frequency sound waves to create an image Computerized tomography – CT- uses x rays for cross sectional imaging Computer Radiography – CR- similar to standard x – ray but an imaging plate connected to a laser scanner for a digital image is used rather than a lead plate. • Digital Radiography – DR – a form of x ray where a digital x ray sensor is used instead of traditional photographic film. • • • • • COMPUTERIZED TOMOGRAPHY - CT COMPUTERIZED AXIAL TOMOGRAPHY- CAT MAGNETIC RESONANCE IMAGING / MRI ULTRASOUND COMPUTER RADIOGRAPHY DIGITAL RADIOGRAPHY TISSUE DENSITY – ITS IMPACT ON RADIOGRAPHIC IMAGES. • The typical radiographic image is composed of black, white and shades of gray. • Black represents air and air filled areas. • Grey indicates soft tissue, and fluid. • White will represent bone. X RAY SAFETY PRECAUTIONS! • The x ray operator needs to be aware that excessive exposure to x rays is dangerous. • Only licensed operators should be using radiographic equipment. • Excessive exposure to x rays may be dangerous. • Safety precautions should include; • • • • Lead aprons and gloves when holding and restraining the animal Limit beam size Keep filters in place Keep lead filters in place THE END !