principles of ultrasonography

how does USG works??

1. WELCOME

2. PRINCIPLE OF ULTRASONOGRAPHY IN VETERINARY PRACTICE

3. CONTENTS INTRODUCTION C0MPONENTS ULTRASONOGRAPHY PHYSICS PATIENT POSITIONING AND PREPARATION BIOLOGICAL EFFECTS PITFALLS OF ULTRASOUND

4. INTRODUCTION Ultrasound/ultrasonography is a medical imaging technique that uses high frequency sound waves and their echoes. Also known as a ‘pulse echo technique’. Similar to echolocation used by bats, whales and dolphins.

5. COMPONENTS Transducers/ probes Monitor and computers

6. ULTRASOUND PHYSICS Characterized by sound waves of high frequency. Sound waves are measured in Hertz(Hz). Sound waves are produced by a transducer. Sound waves reflect back to the probe, while some travel on further until they reach another boundary and they reflect back to the probe. The reflected waves are detected by the probe and relayed to the machine. Use higher frequency transducers to image more superficial structures.

7. PATIENT POSITIONING AND PREPARATION Dorsal recumbency Lateral recumbency Standing Apply ultrasound gel

8. BIOLOGICAL EFFECTS Possible bioeffects : Inactivation of enzymes Altered cell morphology Internal haemorrhage Free radical formation Elevated tissue temperatures.

9. PITFALLS OF ULTRASOUND Ultrasound cannot penetrate air or bone Size of organs is largely subjective Unable to evaluate extra-abdominal structures Cost User dependent results