If you've been on Twitter today, you may have come across a tweet that made you tense your butthole as tight as it is possible to go.
If you haven't, here are the basics: Twitter user BradiusZero shared a scan which appears to show a butt plug embedded within someone's body far higher than a butt plug should be.
"Greatest personal injury case I've ever heard," an accompanying screenshot of a direct message reads. "An estimated Valley attorney, has picked up a client who is suing a sex toy company. Said client purchased a butt plug that was advertised as '100% silicone'. Client wears butt plug to MRI appointment. Much to client's dismay, butt plug in fact has a metallic core. Butt plug is accelerated at the speed of sound [...] into client's chest cavity. Described in memo as an 'anal rail gun'. Client survived with major injuries."
While a horrifying cautionary tale about the dangers of mixing metal butt plugs and MRI machines, there are of course reasons to be skeptical, given how similar it sounds to urban legend formats, and the fact that the scan image first appeared a month ago on Reddit, before being deleted.
Nevertheless, it is still a terrible idea to wear a metallic butt plug to an MRI appointment.
MRI machines work by creating powerful magnetic fields (and radio waves) targeting hydrogen nuclei (protons) in water. As protons are subjected to the magnetic field (about a thousand times stronger than a fridge magnet) their axes line up.
"This uniform alignment creates a magnetic vector oriented along the axis of the MRI scanner," science editor Abi Berger explains in the BMJ.
"When additional energy (in the form of a radio wave) is added to the magnetic field, the magnetic vector is deflected. The radio wave frequency [...] that causes the hydrogen nuclei to resonate is dependent on the element sought (hydrogen in this case) and the strength of the magnetic field."
"When the radiofrequency source is switched off the magnetic vector returns to its resting state, and this causes a signal (also a radio wave) to be emitted. It is this signal which is used to create the MR images."
While this is great for seeing inside the body – especially cartilage and muscles, which other scanning methods can't image as effectively – it's not so great if you happen to be wearing metal, inside or outside your person.