MRIONS MRI Locations

  • 6 Greenwich Office Park, Greenwich, CT.
  • 5 High Ridge Park, Stamford, CT, ground floor

The MRI machines at ONS are Siemens MAGNETOM Aera 1.5T models which use the latest technology to provide patients with a faster and more comfortable MRI exam.  The 70 cm wide bore design helps alleviate that “closed-in” feeling. The powerful 1.5Tesla magnet provides the highest-quality images to aid with diagnostic results. 

All ONS MRI scans are evaluated by a Board-Certified radiologist. Your doctor will review the results with you during your office visit.  ONS MRIs are fully-accredited by The American College of Radiology.



Prior to your appointment, please complete the electronic MRI Safety Screening Form that was sent to you with your appointment reminder.

Please plan to arrive at the ONS MRI Center 30 minutes before your appointment.


Waering clothing or jewelry that contains metal during your exam can degrade or ruin MRI pictures. Metals can also pose serious risk of bodily injury. Therefore, patients will be required to change into a gown to have their MRI. 

In addition,

  • If you have an implanted device, please bring documentation with name, manufacture and model number.

  • No bras or underclothing that has metal on it may be worn in the MRI room.

  • Some fabric contains metal fibers. Clothing containing Lycra, Kool max, yoga pants or clothes by Lululemon may not be worn.

  • Leave all jewelry and body-piercings at home.

  • If you are having a scan in the head or neck area, remove all makeup (some makeup has metallic particles in it). Notify the technologist if you have any facial tattoos, such as eyeliner or eyebrow tattoos.

  • Please bring a list of your current medications.

  • If you experience anxiety related to claustrophobia or fear of tight places, your doctor may prescribe a short term medication to take for your MRI appointment.

Please note: The MRI technologist has the right to determine if you need to change into a gown or not.


  • Hearing Aids

  • Wallets

  • Jewelry, including Body-Piercing 

  • Keys

  • Watches

  • Loose Change

  • Eyeglasses

  • Cell Phones

  • Pagers

  • PDA’s

  • Storage Media

  • Tablets/Laptops/Computers

  • Dentures

  • Prosthetic Devices

  • Insulin Pumps

  • Hair Pins/Bobby Pins


The strong magnetic field used during the MRI exam may interfere with your ability to have this diagnostic test.

Please alert the staff prior to your appointment if any of the conditions below apply to you.  The radiology staff will let you know whether you can have the MRI exam and whether the test needs to be modified for your individual condition.

  • Pacemaker

  • Pregnancy

  • Claustrophobia

  • History of kidney problems

  • Skin tattoos

  • Neurostimulators (TENS-unit)

  • Implanted drug infusion device (i.e., insulin pump)

  • Exposure of metal fragments to your eye

  • Artificial heart valves

  • Aneurysm clips

  • Cochlear implants

  • Metallic implants and prosthesis

  • Vascular stent or stent graft

  • History as a metal worker

  • Shrapnel or bullet wounds

  • Dorsal column stimulators

  • Allergy to iodine, or gadolinium

  • History of diabetes

  • Other conditions you believe to be relevant

MRI FAQ (Frequently Asked Questions)

What is Magnetic Resonance Imaging (MRI)?

MRI technology uses a strong magnet and radio waves to make precise images of internal organs and tissues.  An MRI image provides a much higher level of detail than other imaging technologies, however, in some cases your physician may use MRI images with images from other tests. An MRI exam does not expose you to ionizing radiation that is used for an x-ray or computed tomography (CT) scan.   

Is an MRI Safe?

There are no known biological risks from exposure to the strength of magnetic fields used in medicine today.  However, the strength of the magnet field can pose a physical hazard if some metal medical devices or other metal objects are in the room at the time of the exam. For this reason, you will be asked to change into a gown and socks before entering the MRI room.  To ensure your safety, it is critically important for you to fully complete the MRI safety screening form that was sent to you with your appointment reminder for the on-site technician to review prior to the test.  Always ask questions at the time of your appointment if you are unsure about an implanted medical device.

What can I expect during my exam?

MRI makes a lot of noise. We provide music or ear plugs for your comfort. The approximate time will be anywhere from 25-45 minutes. Our scanner is short bore, so it is wider and shorter than most MRI machines, to make your experience better.

The scanner is wide open on both ends, well-lit and ventilated throughout. A microphone is built into the scanner so we can hear you at all times. We will also be providing a call button to hold that lets us know if you need assistance.

How should I dress for my MRI?

Please wear comfortable clothing without snaps, metal objects or zippers. You will be asked to put on a hospital gown during the exam. A locker will be provided for your belongings.

MRI No-Show / Cancellation Policy

ONS strives to provide each patient with the highest quality of care while attempting to accommodate your schedule. We realize that emergencies and other scheduling conflicts arise and are sometimes unavoidable. However, advance notification allows us to offer your time to another patient who is in need of MRI services.

1) ONS MRI patients must provide a minimum of 24 hours’ notice to change or cancel an appointment. Patients who do not arrive for a scheduled appointment or provide adequate notice will be charged a $100 cancellation fee. This charge cannot be billed to insurance and must be paid in order to reschedule your appointment.

2) Repeated failure to comply with this policy will result in your name being placed on a “Schedule Based on Availability” list. This will require you to call for appointment availability each day and our staff will do what they can to accommodate you as space on the schedule allows.