Climbing onto a stretcher and sliding into a narrow tunnel for a Magnetic Resonance Image can be scary enough for some people. You shouldn't have to worry about getting injured during the process.

In light of some recent stories in the media about the safety of MRI scanners, the Lourdes Health System would like to assure consumers that MRI is a painless and very important diagnostic tool, and that medical professionals are specially trained to make sure no accidents occur.

Samir Talik, MD, a radiologist who oversees MRI services at both Our Lady of Lourdes Medical Center in Camden and Lourdes Medical Center of Burlington County in Willingboro, said thousands of people are scanned annually without incident. Dr. Talik said he has not heard of any recent MRI incidents in southern New Jersey.

"There's really nothing to be concerned about in a unit. It's very safe," he said. "The biggest issue is that some patients become claustrophobic."

First developed in the early 1980s, the number of MRI scanners now in use by hospitals and clinics nationwide number about 10,000. The magnets in today's machines also are significantly more powerful than those in the first scanners, increasing concerns that an unsecured metallic object could be hurled toward the machine or dislodged from body tissue.

An MRI scanner obtains detailed images of inside the body through the use of a magnetic field. The magnetic field aligns atomic particles called protons that are present in most of the body's tissues. Radio waves then cause these particles to produce signals that are picked up by a receiver within the scanner. The signals are characterized using the changing magnetic field, and a computer translates them into images.

While an MRI is safer than an X-ray, there are dangers involved because of the magnets' powerful ability to attract and heat up metallic objects. The magnets are never off. Turning off the electricity will not affect them because they are powered by super-cooled helium.

Dr. Talik said that to reduce the possibility of accidents, MRI technologists at Lourdes' hospitals follow stringent guidelines and question patients extensively about metal objects they may have implanted in their bodies. Technologists also examine patients' medical histories, to see, for example, if a clip inserted to prevent bleeding from an aneurysm is made from a magnetic metal or a safe material such as titanium.

Some patients, depending on their backgrounds or occupations, are given additional examinations before a scan occurs to further ensure safety, Dr. Talik said. For example, welders, plumbers and machine-shop workers may have fine shards of metal in their eyes that could be affected by an MRI magnet. Items that may create a health hazard if exposed to an MRI include:

• A cardiac pacemaker or defibrillator;
• A catheter with metal components;
• An aneurysm clip;
• A medication pump, such as those used to deliver insulin;
• A cochlear (ear) implant;
• Some prosthesis;
• Bullets or shrapnel that may be lodged in the body;
• A penile implant.

Dr. Talik said patients undergoing an MRI wear gowns instead of their normal clothing to avoid dangers that could be posed by metal zippers, buttons, snaps or hooks. Wallets are left outside the examination room because the MRI magnet would demagnetize credit cards and coins could become projectiles, he said. Other items better left outside the exam room include:

• Cellular phones and pagers;
• Watches and some jewelry;
• Hearing aids;
• Pens, paper clips and keys;
• Hair barrettes and pins;
• Belts

Dr. Talik said MRI technologists do not wear metal on the job to prevent accidents. Inside the exam room, oxygen tanks and other metallic objects are either bolted to the floor or walls or are sealed off, he said. "The risk of an MRI shouldn't even be an issue at all," said Dr. Talik. "You do have a set of rules. If you follow the rules, there's zero risk of anything happening at all."

Lourdes Health System is one of southern New Jersey's leading healthcare providers. The system is comprised of Our Lady of Lourdes Medical Center, a 410-bed regional teaching hospital located in Camden, and Lourdes Medical Center of Burlington County, a 259-bed community hospital located in Willingboro.

The Lourdes Health System is sponsored by the Franciscan Sisters of Allegany, NY, and is a member of Catholic Health East, a health system with 31 hospitals on the East Coast.