Information for Potential Participants in Magnetic Resonance Research

Principle of Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS)
Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS) are two closely related techniques which use strong magnetic fields and low energy radio waves to study the human body non-invasively. MRI utilizes signal from water (and fat) to make pictures (images) of the human body, while MRS is used to obtained chemical information. MRI/MRS has several advantages over many other medical imaging techniques. Firstly, MRI/MRS is very versatile in that a wide variety of anatomical, functional and chemical information can be obtained in a single study session. Secondly, the technique of MRI/MRS is completely non-invasive in that it does not require ionizing radiation.

Outline of a typical MRI/MRS research session
The majority of studies at the Yale Magnetic Resonance Research Center (MRRC) are on the human brain and therefore the following describing will be typical for brain studies. The experimental setup for other organs (liver, muscle) will vary only in details. Please note that if you are invited to participate in a study, you will receive a much more detailed description of all procedures. First, you will be asked to lie flat (face up) on a table. You will be asked to wear ear plugs or headphones. Your head will be positioned in a coil that resembles a helmet. Cushions and head bands may be used to minimize your head movement. The table will slowly slide into the magnet, which resembles a long tube with a diameter of circa three feet. Via a view port and mirrors you will be able to see the outside of the magnet. Furthermore, you will have continuous verbal contact with a Yale MRRC researcher. When you are completely comfortable, the actual MRI/MRS session begins and typically lasts a minimum of one hour. During a typical session you will not experience anything except clicking sounds of different tones and strengths.

Potential risks and inconveniences
The United States Food and Drug Administration (FDA) has set guidelines for safe human exposure to magnetic fields and low energy radio waves, and ALL studies performed at the Yale MRRC are designed to be within these guidelines. With more than twenty-five years of experience with human MRI/MRS no harmful biological effects of being in strong magnetic fields have been reported. You may experience some discomfort from lying still for the duration of the studies. A few people have reported side effects that include dizziness, mild nausea and metallic taste. These effects will disappear soon after leaving the magnet. Though the risks involved with MRI/MRS are minimal, some volunteers may not be eligible to participate as will be discussed next.

Eligibility criteria for participants
Before each MRI/MRS session there will be a series of screening and safety questions to determine if you are eligible for participation. In general, eligible participants must be able to answer NO to the following questions:

A. Do you have a cardiac pacemaker, neurostimulator or hearing aid?
The high magnetic field interferes with the proper functioning of implanted devices, like cardiac pacemakers.

B. Do you have any metal in or on your body?
This includes pins, screws, plates, scrapnel, clips and dental braces, but also jewelry and body piercing. Magnetic metals may get bent or moved out of place, while non-magnetic metals will tend to heat up.

C. Are you claustrophobic?
The MRI/MRS magnet is a long but very narrow (three feet) tube. When inside the magnet, the outside is not directly visible thereby emphasizing the impression of a narrow enclosed space. The coil, which resembles a helmet, is even smaller and may enclose your head with less than a few centimeters to spare. The cushions and head band used to minimize head motion will further reduce the available space.
While you will be able to get out of the magnet at any time during the experiment, you should be aware that it is an extremely confined space in which you will need to lie absolutely still for a minimum of one hour for a successful completion of the session.

Confidentiality
All of the information obtained in the studies performed at the Yale MRRC will be kept confidential and only be made available to the investigators. In the event that any reports or publications arise from these studies, care will be taken to avoid incorporating any information that will permit readers to identify you. The Yale Human Invesitigation Committee (HIC) may review records of this research.

Monetary considerations
You will be paid $25 to $35 an hour for a standard MRI/MRS session, depending upon the exact type of study. A standard MRI/MRS session typically takes between one and two hours and that not require anything else from you than lying in the magnet as still as you can. For more extensive studies, in which you are required to participate in simple tasks while in the magnet, a higher monetary reward is possible. Studies that require infusion of substrates, like sugar, may pay as much as $150. However, these studies typically take up to 5 hours, including 3 hours inside the magnet.