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Fund of Scanning
Instrumentation/ Patient Prep
| Term | Definition |
|---|---|
| pulser | provides electrical stimulation to the transducer |
| transducer | converts energies from one form to another (electrical to mechanical & back) |
| Piezoelectric effect | mechanical deformation of crystals |
| receiver | gathers info from the transducer to be processed |
| display | shows image on monitor |
| depth | allows changes in location of the image from deep to superficial |
| focus | allows enhanced resolution to specific areas (carets) |
| gain | overall brightness/darkness of the image |
| TGC | compensates for attenuation; controls brightness/darkness of specific areas |
| dynamic range | contrast of the image; log compressions displayed in decibels |
| cineloop | ability to replay real-time images |
| A-mode (amplitude mode) | spikes that represent strength of echo returning to machine |
| B-mode (brightness mode) | displayed as shades of gray |
| M-mode (motion mode) | represents motion of the B-mode image displayed as a graph |
| frame rate | represents how often an image is updated |
| pixels | digital memory matrix of image; gray scale we see on screen; typical machine has 512x512 matrix |
| Abdominal scan prep | NPO at least 8 hrs prior |
| Pelvic exam prep | 32 oz of water prior to fill bladder |
| Vascular scan prep | NPO at least 8 hrs prior for abdominal vessels |
| Cardiac scan prep | no prep needed |
| near gain | controls brightness at top of image |
| far gain | controls brightness at bottom of image |
| near zone | concentrates sound beam at the top of the image |
| far zone | concentrates sound beam at the bottom of the image |
| annotation should list: | scan orientation, organ of interest, & location |