Intro to General Principles of MSK Imaging Part 2 Flashcards
How to view a radiograph
- view a plain film as if you are facing the patient
- a minimum of 2 markers is usually imprinted on every radiograph
Identification markers
- provides pt identification
- establishes anatomic side (R or L)
- weight bearing or (ERECT) indicates pt was standing for exam
- decubitus (DECUB) indicates that the pt was recumbent
- inspiration (INSP) & expiration (EXP) are used in comparison films of the chest indicating the state of respiration
Describe the saying “one view is no view”
- the minimal radiographic examination includes 2 views of the imaged body part at right angle to each other
Define angles of projection
- the path of the x-ray beam as it travels from the X-ray tube through the pt to the image receptor
How many dimensions does a single X-ray provide
- a single X-ray provides only 2 dimensions (LxW)
How do you determine depth with an x-ray
- to determine depth a 2nd x-ray is required at a right angle (90º) to the 1st
What are the most common views for X-rays
- AP (anterior to posterior)
- lateral: x-ray beam has traveled through the body at right angles to the AP or PA projection/view
- oblique: involves rotation of a body part so that the beam travels through the body part at an angle between the AP & lateral views
Radiographic positions that best visualize intervertebral foramina versus zygapophyseal
- Intervetebral: oblique 45º (cervical spine), lateral (thoracic spine), lateral (lumbar spine)
- Zygapophyseal: lateral (cervical spine), oblique 70º (thoracic spine), oblique 45º (lumbar spine)
What is the only body part that is evaluated with a PA view instead of an AP view
- hand
Define position
- the pat’s physical position
- general body position (supine, seated, standing)
- wbing versus non-wbing
- the body part closest to the image receptor offers the best detail
Primary radiographic body positions
- upright
- seated
- recumbent
- supine
- prone
- trandelenburg
Factors related to image quality
- Photographic: density = blackness, contrast = variation amongst densities
- Geometric: detail = sharpness/motion, distortion = object is not perpendicular to X-ray beam
What is included in the routine radiographic exam
- offers the most visualization of structures with the least number of radiographs
- lowest amount of radiation to create a quality image study
- ACR appropriateness criteria
Possible radiographic results from routine exam
- Positive for hypothetical clinical diagnosis
- Negative for hypothetical clinical diagnosis
- Negative for hypothetical clinical diagnosis but raises suspicion for an alternate diagnosis
- Inconclusive: additional imaging needed
- Wrong: False Neg./False Pos.
What view is a chest radiograph always taken at
- PA view
What are the different views for cervical spine plane films
- AP view
- Lateral view
- Open mouth view (odontoid/dens view)
- Anterior Oblique view (right or left)
- Swimmers view (addresses the issue with poor visualization of C7; AKA modified lateral projection of cervical spine)