One of the major advances in medical techonolgy in recent time has been magnetic resonance. It allows a view into the human body that in the past could only be achieved with surgery. It is a common used tool to diagnose a long list of possible medical conditions. It does this by creating magnetic fields that align the magnetization of some atomic nuclei in the body, and radio frequency magnetic fields are applied 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.
The main concern is how the metal will react to the fields created within the MRI machine. With metals that are ferromagnetic(magnetic metals) can be displaced or misshape. The other concern is that if the material is conductive, it can cause the jewelry to heat up causing discomfort and posible burns. It can also effect the imaging of the MRI scan which is one of the main reasons that MRI Techs request that jewelry, especially located in the area being scanned be removed. Though I have to state that I have seen no cases of reactions to Implant Grade Steel or Titanium jewelry or heard of any case but there is a risk.
The reason is the process used to create the alloys. In studies on 316L and titanium neither produced ferromagnetic fields or had any reaction or caused the scan to malfunction. For a more detail explanation go to http://safepiercing.org/wp-content/uploads/2009/03/Piercing_MRI.pdf. Please understand that substandard jewelry that is not certified ASTM Implant Grade may not have the same reactions. Whenever in doubt the jewelry should be replaced with a non-metalic material such as Acrylic, monofilament or glass. Another option if you are already at the office is requesting catheter tubing of the correct gauge be placed in the piercing.
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