Introduction to Radiology Flashcards
radiography includes
x-rays and plain films
how does an x-ray work?
x-rays (photons) penetrate patient
transmitted x-rays are detected and used to create an image
radioluscent
less dense
film black without absorption
radiodense
more dense
film white without penetration
the lower the atomic weight (more density) the more ___________ it is to x-rays
transparent
attenuation
degree to which x-rays are absorbed/deflected by the body part
bones which are ______ density than surrounding flesh, attenuate ____ radiation and cast a _______ shadow
higher; more; heavier
the image quality of x-rays is dependent upon
thickness of body part; motion; scatter; magnification; distortion
magnification
as object moves from film and closet to x-ray source, it’s shadow becomes larger
distortion
occurs when the object is not perpendicular to the x-ray beam
utility of x-rays
chest, skeleton, abdomen
floroscopy
x-ray movie
continuous field of x-rays transmitted through pt. with detecter configured to video display
radiation risk is increased
utility of floroscopy
contrast studies, various procedures
computed tomography
rotating beam of x-rays transmitted through pt. to multiple detectors; pt. is advanced through a scanner; complex math converts data into image
the radiation risk of a CT scan is _______ than an x-ray
greater
utility of CT
faster than MRI; neurology, chest, abdomen and pelvis, extremities
nuclear medicine
radioscope tagged to biologic molecule and together form radiotracer; radiotracer is internalized and radioactivity is detected outside of patient and created into image
utility of nuclear medicine
measures function and physiology; PET; tech-99m bone scans; tagged WBC; tagged RBC; HIDA (liver) scan
sonography
ultrasound
high frequency is transmitted into pt, reflected sound is analyzed by transducer, which creates image
can detect movement and direction–blood flow
utility of sonography
pediatric, vascular imaging, gallbladder, female pelvis, kidneys
magnetic resonance imaging
protons are controlled by strong magnets and altered by radiofrequency pulses; as protons “relax” radiofrequency signal (amplitude and phase) are measured and assigned intensity values and positioning to create imaging
T1
fat is bright, water is dark
good anatomic detail
T2
water is bright, fat is dark
less anatomic detail but food for measuring inflammation
MRI utility
neuroradiology, musculoskeletal radiology, pediatric imaging
physical therapist’s role in imaging
- recognize when MSK imaging is needed to complete a comprehensive examination
- integrate formation from the written report into the PT POC
- understand reading imaging to evaluate beyond the written report
- recognize when imaging is needed and not needed to promote an optimal patient outcome
- communicate effectively regarding MSK imaging with treating physicians, radiologists, and other healthcare providers
use diagnositc imaging only when positive findings will…
alter the intervention or change the plan of care
diagnositic images are considered _______ ____ and therefore need the context of the whole examination
special tests
