Term
| Why are X-rays used in radiology? |
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Definition
X-rays are produced by bombarding a tungsten target with an electon beam. X-rays are a form of electromagnetic energy similar in several respects to visible light. The fundamental difference between X-rays and light rays is their range of wave lengths.
The wave lengths of X-rays being shorter than those of ultraviolet light.
***This useful science of diagnostic radiology is based on this difference, since many substances that are opaque to light are penetrated by X-rays. |
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Term
| Who invented X-rays (test question) and how did he do it? |
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Definition
Wilhelm Conrad Roentgen - KNOW - TEST QUESTION
in 1895 was experimenting with an apparatus that, unknown to him caused the emission of rays as a by-product. Professor Roentgen names these rays X-rays and he found by using photographic paper he could make a picture of his hand showing details for the bones, soft tissue and a ring he had on. Six years later the first Nobel Prize in Physics was awarded to Dr. Roentgen for his discovery. |
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Term
| How does radiodensity relate to composition? (TEST QUESTION) |
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Definition
The more dense the composition is the whiter it shows up on film
Spectrum from whitest (most dense) to darkest (least dense)
Lead
Bone
Muscle
Blood
Liver
Fat
Air |
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Term
| How does radiodensity relate to thickness? |
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Definition
The more thick a material is the whiter it shows up
Ex - compact bone shows up whiter than spongy bone
The view (lateral vs anterior) makes a difference
Ex - Spinous process of vertebrae is harder to see (darker) in a lateral view as opposed to an anterior to posterior view |
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Term
| What is the standard routine chest x-ray? |
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Definition
Posterior Anterior with the patient standing
The film is pressed up against the chest (want the chest in focus - being closer makes it more focused) and the X-ray goes from posterior to anterior
X-rays travel from behind - enter the back and exit the chest onto the film |
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Term
| How can be lateral chest x-rays be useful? |
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Definition
In a standard PA chest X-ray it can be difficult to determine the depth of an object that does not belong (for example a bullet)
A lateral chest X-ray can tell one where that bullet is depth-wise |
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Term
| What is the lordotic view? |
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Definition
| Chest X-ray at an angle (the patient leans back away from the X-ray |
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Term
| What can fluoroscopy be used for? |
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Definition
| Gastrointestinal (GI) exams |
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Term
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Definition
Also know as a C.A.T. scan which stands for Computerized Axial Tomography
It’s a special kind of X-ray that can produce "3-D" pictures of a cross section of a part of the body.
CT scans can detect some conditions that normal X-rays cannot. This is useful in preventing unnecessary surgeries |
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Term
| Compare radiolucent and radiodensity |
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Definition
Radiolucent - shows up as dark because there is less material and the X-rays just pass through (lucent)
Ex - air
Radiodensity - show up as white because there is dense material and the X-rays cannot pass through easily |
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Term
| Compare a lung nodule and a lung mass |
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Definition
Lung nodule - < 3cm
Lung mass - > 3 cm |
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Term
| What does emphysema look like on a X-ray? |
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Definition
| There is excess air in the chest from the lungs being hyperinflated |
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Term
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Definition
Air between the lungs and chest
Could occur from something like a punctured lung |
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Term
| What is the silhouette in a chest X-ray? |
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Definition
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Term
| What is calcified and calcinosis? |
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Definition
Calcified just shows up as white and its normal bone
Calcinosis is the formation of calcium deposits in any soft tissue. It is abnormal. The chest X-ray is white where it's not supposed to be. |
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Term
| How much radiation is generated in a MRI (TEST QUESTION)? |
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Definition
| No radiation is used or generated in a MRI |
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Term
| What is a contrast study (TEST QUESTION)? |
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Definition
| Contrast studies involve the use of barium sulfate solutions, air or special dyes, etc. to enhance the X-rays of various parts of the body |
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