Uses And Purpose Of The Technology

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1 NAME AND PURPOSE OF THE TECHNOLOGY The MRI – Magnetic Resonance Imaging – is a non-invasive medical procedure that uses a powerful magnetic field and radio frequency pulses to produce detailed images of soft-tissue, organs, blood vessels, bone and nearly all other internal body structures. These detailed images allow physicians to evaluate various parts of the body and diagnose and treat various medical conditions. Unlike X-rays and CT scans, MRI machines produce 3D images of the body without the use of ionizing radiation. The traditional MRI machine is a large cylindrical tube surrounded by a powerful magnet, with the patient situated on an examination table that slides into the centre of the tube. Doctors often use the MRI to view…show more content…
Rather than using ionising radiation like the X-ray or CT scan, the MRI uses a strong magnetic field and radio waves to image both soft tissue and bone structures. The strong magnetic field is created by passing an electric current through wire coils located in the machine and around the body part being imaged. The body is made up of around 60% water, and water molecules contain hydrogen protons which become aligned in a magnetic field. Hydrogen protons are also abundant in fat, making them ideal for imaging purposes. The strong magnetic field from the MRI aligns the proton ‘spins’ – “The hydrogen proton can be likened to the planet earth, spinning on its axis, with a north-south pole. In this respect it behaves like a small bar magnet. Under normal circumstances, these hydrogen proton “bar magnets” spin in the body with their axes randomly aligned.” (Berger, 2002) Under the MRI’s strong magnetic field, the protons’ axes align, creating a magnetic vector oriented along the axis of the MRI machine. The machine also produces additional energy in the form of radio waves that redirect the uniformed alignment of the hydrogen protons. The protons absorb the energy from the radio frequency and flip their spins. When the radio frequency source is turned off, the protons gradually return to alignment, and the magnetic vector returns to its resting state. This causes a radio signal to be emitted that is measured by receivers in the machine and used to create an
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