Question 17

Write notes on:
•    The principles of ultrasound
•    Transducer properties and image resolution
•    The Doppler effect

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College Answer

This question was taken from core syllabus that requires level one (L1) understanding. Physical principles of ultrasound can be illustrated by outlining how ultrasound waves are generated from piezoelectric crystals, how they travel through the tissues, how they interact with different tissue planes and how the reflected waves return to the transducer and create images. Properties of ultrasound transducers include different geometric configurations of transducer probes and frequency-wavelength- bandwidth properties of the crystals used in diagnostic ultrasound. Understanding of physical concepts of image resolution including its various aspects (e.g., spatial, temporal, contrast resolution) is required to address the next portion of the question. “Doppler effect” can be illustrated by a definition and equation along with some practical implications. This question was not answered well by majority of the candidates. Lack of knowledge and limited understanding resulted in poor average mark.