P4.d - Ultrasound 0.0 / 5 ? PhysicsWavesGCSEOCR Created by: simonhwCreated on: 25-01-16 14:49 Name four uses of ultrasound. ∞checking of foetuses ∞investigating heart and liver problems ∞looking for tumours ∞measuring speed of blood flow 1 of 10 What does a high powered ultrasound break down in the body? Kidney and other stones. 2 of 10 How does ultrasound help in cataract surgery? Ultrasound breaks down the opaque lens in a cataract sufferer's eye. The defective lens is surgically removed and replaced by an artificial one. 3 of 10 What happens to the ultrasound pulses between different tissues and organs? Some are reflected and some are transmitted. 4 of 10 What happens to the returning echoes from the scan? They are recorded and used to build up an image of the internal structure. 5 of 10 Why is a gel put between the ultrasound probe and the patient's skin during the scan? Without it, almost all ultrasound would be reflected at the skin and the image would be bad. 6 of 10 How do you work out the depth of each structure in the body? Speed = distance/time 7 of 10 What two things does the proportion of ultrasound reflected depend on? ∞the densities of tissue ∞the speed of sound in tissues 8 of 10 What do Doppler Ultrasound scanners do? Detect movement. 9 of 10 Name two advantages of ultrasound over x-rays. ∞they differentiate between soft tissue better ∞don't damage living cells 10 of 10
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