Q.Explain the working of MRI

Step 1. MRI does not use ionising radiation at all; instead the patient is placed inside a powerful magnetic field, generated by passing electric current through wire coils in the scanner.

Step 2. Radio-frequency pulses are then sent into the body by additional coils; these pulses temporarily re-align hydrogen atoms that occur naturally throughout the body's tissues, without producing any chemical change in the tissue.

Step 3. As the hydrogen atoms relax back to their normal alignment after each pulse, they emit small amounts of energy that vary depending on the type of tissue they are located in - fat, muscle, fluid and other tissues each emit a slightly different signal. …

Trace MRI's working step by step: magnetic field, radio pulses, hydrogen realignment, emitte …

• Describing MRI as using X-rays or radiation, when its defining feature is that it uses no ionising radiation at all. …