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Welcome to Radiology. Introduction and Chapter 1. What to Expect. You are going to learn a lot in a short period of time. This is a very fast paced class, so you will need to keep up. If you ever have any concerns or questions, please let me know. My contact information.
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Welcome to Radiology Introduction and Chapter 1
What to Expect • You are going to learn a lot in a short period of time. • This is a very fast paced class, so you will need to keep up. • If you ever have any concerns or questions, please let me know.
My contact information • Please use it with care. • I prefer texts, but be sure to sign who you are. • Krista D. Wilkerson, R.V.T. • 210-601-0170 • kwilkerson@vettechinstitute.edu • Midnight_cobra@yahoo.com
Other things to know • We will be dividing into groups for the lab portion of this course. • 4-5 people per team. • I will assign the groups and will have final say as to who will be in a group with one another. • Groups will be assigned by Friday.
How I grade: • There will be a minimum of one unannounced quizz per week. • I give homework on Friday that is due on Monday. • Case reports will also be due on Mondays. • Anything that is late will be penalized 10% a day. • Homework counts once, quizzes twice, and exams 3 times.
Lab portion of class • Kennels do count in this class. • You will receive a lab participation grade. • If you are late to lab you are penalized 5 points. • If you are absent from lab you are penalized 10 points. • Your portion of the portfolio will be counted as a percentage of your attendance. • Your final radiographic portfolio will count 3 times and consist of 10 radiographs that you wish for me to grade (we will go over this portion in detail as the class goes on).
Lab portion Continued • First lab will be on Monday, September 19. • You will be assigned a particular time in which you will be responsible for taking your radiographs of an assigned animal. • IF YOU ARE PREGNANT OR BECOME PREGNANT DURING THIS CLASS, SEE ME IMMEDIATELY!!!!!!!!!!!!!!!!!!!
Tentative Course Schedule • There will unannounced “pop” quizzes every week. • There will be a “safety quiz” on September, 6. You must pass this quiz with an 80 or higher in order to participate in lab. • Exam 1 will be Thursday, September 15 over chapters 1-12. • Exam 2 will be on Wednesday, September 28 over chapters 13-17. • Final exam will be October 19 and will be comprehensive. • Final lab portfolio is due Tuesday, October 18.
Soo…….. • Lets have fun, learn a lot and DO THIS!!
Chapter 1 • Why is radiology important? • What makes a good radiograph? • What is a radiograph?
answers • Radiology is important because it allows us to visualize inside an animal in a very non-invasive way. • If a radiograph is diagnostic, then it is considered a “good” radiograph.
So what is a radiograph? • A radiograph is a visible image on x-ray film. • Image receptors and detectors convert invisible ionizing radiation into a visible image. • Understand the difference between a radiograph and an x-ray.
X-rays • X-rays are the electromagnetic radiation similar to visible light but of shorter wavelength. • Remember a radiograph is the actual image.
What is Electromagnetic Radiation? • Method of transporting energy through space and is distinguished by wavelength, frequency and energy. • Different forms of electromagnetic radiation. • Radio waves, television waves, radar, infrared waves, visible light, gamma rays, UV rays, etc.
2 Characteristics of Electromagnetic Radiation • 1. Particles • 2. Waves
Particles • Essentially atoms. • What makes up an atom? • Protons (positive charge) • Neutrons (neutral charge) • Electrons (negative charge)
The Atom • Nucleus has protons and neutrons • Electrons are negative and travel around nucleus in orbits called shells.
Waves • All radiant energy travels in wave form along a straight path and is measured by it’s wavelength. • Wavelength- distance between 2 corresponding points on a wave.
Wavelength • Shorter wavelength=high frequency=greater energy • Longer wavelength=low frequency=lesser energy • High frequency=more penetrating power the energy has through space and matter
So x-rays with shorter wavelengths penetrate farther than x-rays with longer wavelengths.
Electromagnetic Spectrum • Electromagnetic Radiation is grouped according to wavelength and frequency. • This grouping is called the Electromagnetic Spectrum.
How are x-rays produced? • When electrons are slowed or stopped by the atoms of a target area, x-rays are produced. • This target area is inside the x-ray tube. • Once the electrons strike the target area, an x-ray beam is created.
Definitions • X-ray beam- composed of bundles of energy that travel in waveform. • Quanta- these bundles of energy, may also be called photons. • Photons consist of pure energy and are “carried” by the wave.
Physical Properties of X-ray Electromagnetic Radiation • What have we learned so far? • 1. Wavelength is a variable. • 2. X-ray electromagnetic radiation travels in a straight line. Direction can be altered but will continue in a straight line. • 3. X-rays have short wavelengths- so therefore penetrate objects. Can be absorbed by object but depends on the physical density of that object (the atomic #).
Properties continued… • And more that we know.. • 4. Fluorescence-property that can emit visible light- some substances fluoresce after absorbing electromagnetic radiation of shorter wavelength (glow in the dark). • Question: What is a form of electromagnetic radiation of short wavelength??
More Properties • 5. X-rays produce an invisible image on photographic film that can be viewed when film is processed (this is why you can’t see the image before processing).
And more properties • 6. X-rays can excite or ionize the atoms and molecules of the substances including gases through which they pass. • Excitation- when an electron is moved to higher energy level within the atom • Ionization-when outer electron is removed and leaves atom with a positive charge. • Question: Which process takes more energy?
And still more properties • 7. X-rays can affect living tissue. • Why do we wear protective equipment? • Can cause chemical damage or changes within or near cells.
How are x-rays generated? • When electrons collide with matter. • On our modern x-ray machines we have something called the x-ray tube. • X-ray tube consists of: • Cathode-negatively charged electrode. • Anode-positively charged electrode.
Now time for the magic • Electrons have a negative charge and are at cathode end of tube. • Anode has positive charge so electrons want to travel to anode (opposite attract). • When electrons (negative charge) collide with anode’s positively charged target, x-rays and heat are produced.
Collisions everywhere • When this collision and magical event of x-ray formation occurs, do you think more heat or x-rays are produced?
answer • Only 1 % of collision is x-rays, while other 99% is heat.
Brief History of x-rays • 1890- Professor in Philadelphia discovered x-rays but did not feel that they were important. • 1895- Wilhelm Conrad Roentgen discovered x-rays and realized their medical importance. He mistakenly discovered while working on cathode rays.
Let’s Review • Questions??????