Imaging Flashcards
Describe a radiography (plain x-ray)
Noninvasive imaging study to identify and screen for bone and joint injuries, lung or heart disease, foreign objects etc
What are the advantages and disadvantages of an x-ray?
Advantages: Inexpensive, convenient and quick
Disadvantages: Exposure to radiation, poor for subtle fractures and soft tissue injuries. Requires 2 different projections, since structures may be superimposed on each other
Describe an MRI
Noninvasive test that provides sectional imaging of bone and most soft tissues.
T1- demonstrates fat within tissues and assesses bony anatomy
T2- Assesses soft tissue structures
Sectional images can be configures into a 3-D model
What are the advantages and disadvantages to an MRI?
Advantages: High-quality image of almost any structure of the body.
Disadvantages: Relatively expensive, time-consuming, can’t be used if patient has implanted metal device, claustrophobic environment
Describe a CT scan
Plain film x-ray slices that are enhanced by a computer to improve resolution. It is multiplayer so can image in any plane; therefore, tissue can be viewed from multiple angles
Sectional imaging of bone and most soft tissues
What are the advantages and disadvantages of a CT scan?
Advantages: Proves high quality imaging of bone, soft tissue, and blood vessels all a the same time better than x-ray (complex fractures, facet dysfunction, disc disease, or stenosis.
Disadvantages: Large amounts of radiation, relatively expensive
Describe an angiography
An invasive procedure in which a catheter and contrast material are used in conjunction with x-rays, CT, or MRI to visualize blood vessels throughout the body
When do you use a bone density scan or duel-energery x-ray absorptiometry (DEXA)
Gold standard for measuring bone mineral density.
Delineates osteopenia from osteoporosis
Describe a diagnostic ultrasound.
Noninvasive procedure for helping diagnose partial tendon tears, soft tissue lesions, and swelling. Can be used as biofeedback to facilitate muscle activation (rehabilitative ultrasound)
What are some limitations of a diagnostic ultrasound?
Limited by contrast resolution, small viewing field, how deep it penetrates, and poor penetration of bone. Interpretation of data is subjective so results depend on skill of operator.
When is a Positron Emission Tomography (PET) scan used?
Used to detect non perfusing areas of the heart or to evaluate the brain in suspected areas of dementia, stroke, seizures and tumors
Describe a Myelography
Invasive technique using water-soluble dye. Dye is visualized as it passes through vertebral canal to observe anatomy within region
Rarely used due to better and safer information that can be gained from a CT scan or an MRI
