- published: 27 Apr 2012
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Magnetic resonance imaging (MRI), nuclear magnetic resonance imaging (NMRI), or magnetic resonance tomography (MRT) is a medical imaging technique used in radiology to visualize internal structures of the body in detail. MRI makes use of the property of nuclear magnetic resonance (NMR) to image nuclei of atoms inside the body.
An MRI scanner is a device in which the patient lies within a large, powerful magnet where the magnetic field is used to align the magnetization of some atomic nuclei in the body, and radio frequency fields to systematically alter the alignment of this magnetization . This causes the nuclei to produce a rotating magnetic field detectable by the scanner—and this information is recorded to construct an image of the scanned area of the body. Magnetic field gradients cause nuclei at different locations to rotate at different speeds. By using gradients in different directions 2D images or 3D volumes can be obtained in any arbitrary orientation.
MRI provides good contrast between the different soft tissues of the body, which makes it especially useful in imaging the brain, muscles, the heart, and cancers compared with other medical imaging techniques such as computed tomography (CT) or X-rays. Unlike CT scans or traditional X-rays, MRI does not use ionizing radiation.
John Felix Anthony Cena (/ˈsiːnə/; born April 23, 1977) is an American professional wrestler and actor. He is currently signed to WWE as a member of its Raw brand.
In WWE, Cena has won 19 championships in total, including 12 world titles (having won the WWE Championship a record 10 times and the World Heavyweight Championship twice). In addition, Cena has also won the WWE United States Championship three times, and is a four-time Tag Team Champion, having held the World Tag Team Championship twice (once each with Shawn Michaels and Batista), and the WWE Tag Team Championship twice (once each with David Otunga and The Miz). Cena also won the 2008 Royal Rumble match, and is a two-time Superstar of the Year Slammy Award winner (2009 and 2010). He also has the fourth highest number of combined days as WWE Champion behind Bob Backlund, Hulk Hogan and Bruno Sammartino.
Cena started his professional wrestling career in 2000, wrestling for Ultimate Pro Wrestling, where he held the UPW Heavyweight Championship. In 2001, Cena signed a contract with the World Wrestling Federation (WWF) and was sent to Ohio Valley Wrestling (OVW) where he held the OVW Heavyweight Championship and the OVW Southern Tag Team Championship (with Rico Constantino).