“MRI (magnetic resonance imaging) is a fairly new technique that has been used since the beginning of the 1980s.
The MRI scan uses magnetic and radio waves, meaning that there is no exposure to X-rays or any other damaging forms of radiation.
Radio waves 10,000 to 30,000 times stronger than the magnetic field of the earth are then sent through the body. This affects the body's atoms, forcing the nuclei into a different position. As they move back into place they send out radio waves of their own. The scanner picks up these signals and a computer turns them into a picture. These pictures are based on the location and strength of the incoming signals.
With an MRI scan it is possible to take pictures from almost every angle, whereas a CT scan only shows pictures horizontally. There is no ionizing radiation (X-rays) involved in producing an MRI scan. MRI scans are generally more detailed, too. The difference between normal and abnormal tissue is often clearer on the MRI scan than on the CT scan.”*
*http://www.netdoctor.co.uk/health_advice/examinations/mriscan.htm
A few weeks ago I discovered that the outrageously priced CT scan I did in January was not of my entire head as I has previously thought, rather only - I kid you not - of my nostrils.
I am therefore still concerned about the possibility of having something in my brain that is causing the headache.
I went to hospital today for the MRI scan. I had already had one done, in January, for my bad shoulder so I knew how it worked.
I was asked to change and was given a white gown to put on. A little boy who had been put to sleep was wheeled by and taken to the MRI room. I was told I would be in after him.
I was strapped to the bed and pushed inside the tunnel, a large, cylinder-shaped magnet. As the machine emits a loud banging sound, patients are always supplied with headphones (usually accompanied by soothing music) to occlude the noise.
There was a problem with the headphones, and I was handed a couple of earplugs instead.
The scan lasted for about twenty loud minutes.
As much as I would like something to show up in my tests, in a way I am hoping nothing will show in this MRI, given the pivotal role the brain plays in the human body.
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