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

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 Exam 2 will be on Wednesday, September 28 over chapters 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.

Diagnostic vs. Non- Diagnostic

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.

Inside the x-ray tube

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 Professor in Philadelphia discovered x-rays but did not feel that they were important Wilhelm Conrad Roentgen discovered x-rays and realized their medical importance. He mistakenly discovered while working on cathode rays.

Let’s Review Questions??????