[Lab] Ultrasound Physics, Terminology and Knobology Flashcards
What kind of diagnostic data is point of care ultrasound (POCUS) use for?
Specific questions
i.e. Pericardial effusion, intraperitoneal fluid, gallstones, hydronephrosis
What are the main limitations to using point of care ultrasound?
Operator dependent
Poor image quality with fat and/or air
What type of imaging are low frequency probes good for?
Deep structure (aorta, kidney, GB) imaging - penetrate deeply but with poor resolution
Sound waves have long wavelengths
What type of imaging would you use to view superficial structures such as blood vessels, breast/thyroid tissue?
High frequency probes - poor penetration but good resolution
sound waves have short wavelengths
Identify the structures in this image
Liver
Kidney
Diaphragm
Morrison’s Pouch
Identify the structures
Spleen
Kidney
What is acoustic shadowing on US?
When a sound wave hits reflective surface and the back of the structure looks hypoechoic
What type of probe is used for higher frequencies?
Linear/vascular probe
What is the sector or phased array probe use for?
Cardiac probe
Lower frequencies
Small footprint for intercostal scanning
High frame rates
What is the curvilinear probe used for?
Abdomen
Even lower frequencies than sector
Large footprint
What is posterior acoustic enhancement on ultrasound?
Increased echogenicity posterior to an anechoic structure
What is edge artifact on ultrasound?
What is mirror artifact on ultrasound?
Mirror image of structure imaging due to reflective surface
distal in relation to the probe
What are the 4 main motions of the ultrasound probe?
Sliding
Rocking
Fanning/sweeping
Rotating/twisting
What is the ALARA principle?
using As Low As Reasonably Achievable exposure to avoid harming humans
While US has not been shown to be harmful, the principle comes from ionizing radiation in XR
