Clinical Anatomy 1 Nomenclature/terminology Flashcards
What are three forms of ionizing radiation?
- Plain X-ray
- Computed tomography (CT scan)
- Nuclear medicine imaging
What are two forms of non-ionizing radiation?
- Ultrasound
2. Magnetic resonance imaging (MRI)
What is a non-sectional image?
Conventional or plain X-rays
What are 5 Sectional images?
- Computed tomography (CT scan)
- Positron emission tomography (PET)
- Single photon emission tomography (SPECT)
- Magnetic resonance imaging (MRI)
- Ultrasound
What are 2 Nuclear Medicine technologies?
- Positron emission tomography (PET)
2. Single photon emission tomography (SPECT)
Who discovered X-rays and when?
- Discovered in 1895
- Wilhelm Conrad Roentgen (German physicist)
When was x-rays first used in medicine?
First used to image human tissue in 1896
How do x-rays work? (2 steps)
- X-ray machine sends one radiation beam that passes through the body and is detected on photographic film or detector plate placed opposite the X-ray source
- X-rays are absorbed or scattered to varying degrees by different tissues in the body
* x-rays are absorbed depending on the density of the tissue. This is the basis for radiographic image formation and contrast.
What are 2 standard projection for chest x-ray?
- Posterior Projection
2. Lateral Projection
What are radiographs?
- Also known as x-rays
- Is a superimposition of shadows of many different structures
- Are photographic negative
Why are there shadows in x-rays?
Shadows are created due to air
What are images in x-rays?
Shadows of more dense and less dense tissues of a part of the body
What are denser tissues in x-rays?
- They absorb more x-rays and cast a white shadow known as Radiodense or radiopaque
- Compact Bone is more dense than spongy bone
- This is seen as increased radiodensity in an x-ray
What are less dense tissue in x-rays?
- Allow most of the x-ray to pass through creating a grey/darker shadow known as Radiolucent
- Spongy bone is less dense due to the amount of cavities.
- This is seen as increased radiolucency
What is Radiodense?
- Denser tissue in an x-ray that absorbs x-rays
- Radiopaque
What is Radiopaque
- Denser tissue in an x-ray that absorbs x-rays
- Radiodense
What is Radiolucent?
- Less dense tissue in an x-ray
- Radiolucency are shadows that don’t absorb the light
What is Density interface?
Refers to the anatomical boundary between structures of different densities that about one another
-The boundary from the heart and lungs.
What are 3 kinds of medical images generated by x-ray radiation?
- Conventional (plain) X-ray imaging
- Contrast X-ray imaging
- Fluoroscopy
How are plain x-ray images sharper?
Structures closer to the film cassette are sharper
In a lateral view of an chest x-ray where should the film cassette be placed?
Film cassette placed against the Left side because it is closer to the heart (sharper image).
What is Contrast x-ray imaging?
- Use contrast agent or dye to improve image contrast of structures that do not have inherent differences in radiographic density
- Used when two structures have similar density (ex. Density tissue of the esophagus and heart are similar)
What dye is used in blood vessels?
- Water-soluble iodine dyes
- Using dye in blood vessels in known as angiography
What is angiography?
- Using water-soluble iodine dye in the blood vessels
- Help to diagnose an obstruction, blockage,
narrowing (“stenosis”), aneurysm (ballooning)
of a blood vessel - Stenosis- the abnormal narrowing of a passage in the body
- Aneurysm- an excessive localized enlargement of an artery caused by a weakening of the artery wall
What is Stenosis?
The abnormal narrowing of a passage in the body
What is Aneurysm?
An excessive localized enlargement of an artery caused by a weakening of the artery wall. (ballooning of a blood vessel)
What dye is used for the urinary system?
Water-soluble iodine dyes
- Used to detect urinary tract obstructions
due to kidney stones or tumors, congenital
anomalities
What dye is used for the Gastrointestinal tract?
Barium sulphate
*Used for the detection of ulcers, diverticulum, hiatus hernia, esophagitis, tumors, polyps
What are 2 risks using contrast x-ray imaging?
- Allergic reaction
2. Small Bowel obstruction
Why are contrast x-rays less used/being replaced? (3 reasons)
Being replaced by techniques such as CT scan, MRI, and Ultrasound scanning because they all produce:
- Better-quality images
- Cause less discomfort
- Involve fewer risks to health
What is Fluoroscopy?
Study of moving body structures in real time imaging
- Allows for the observation of movement
- Commonly used to observe the gastrointestinal tract (Assists the physician in insertion of Gastrostomy tubes, intravenous cardiac insertion)
How does fluoroscopy work? (3)
- Controlled with a switch
- Strike a fluorescent plate coupled to and image intensifier and a TV camera
- Images are transmitted to a TV monitor