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What is Pulse echo principle is used by which modality? and explain in detail?
Pulse Echo Technique is used in Ultrasound, which sho-duration Ultrasound pulses are transmitted into the region to be studied, and Echo signals resulting from scattering and reflection are detected and displayed. The depth of a reflective structure is inferred from the delay between pulse transmission and echo reception. CT scan is based on Linear Attenuation of X Rays. MRI is based on Gyromagnetic propey of H+ ions.