How does MRI work?
Radio frequency (RF) pulse is applied to protons in body tissue, and excites the protons. When the protons return to the equilibrium state, they emit energy as RF signal. These RF signals are picked up and analyzed and using a computer, creates an image. By varying the sequence of RF pulse applied & collected, different types of images are created. MRI DOES NOT USE IONIZING RADIATION (X-RAY).
Why is safety important?
Because the Magnet is over 45,000 times stronger than the earth's magnetic field, safety screening is very important. The safety questionnaire must be filled out entirely and accurately. This will ensure that the patient does not have anything in or on his/her body that could cause problems during the MRI. Patients should please empty pockets prior to the MRI, as metal objects may become projectiles in the magnetic field.
Why would I need Pre-MRI orbit x-rays?
If the patient has ever done any welding, machinist work or metal work in his/her lifetime or had metal removed from his/her eyes, pre-MRI orbit x-rays may be required. The magnetic force of the machine is so strong that if there is any metal in the eyes, it could move and cut the optic nerve. An x-ray needs to be done at WDH before 5 pm on the day of the MRI or sooner to ensure there is no metallic foreign body in the eyes.
Pre-MRI orbit x-rays are part of the MRI charge and does not cost extra. If there is shrapnel or metal of any kind in any other area of the body that could cause harm or injury if exposed to a powerful magnetic field, a separate order for x-ray of that part of the body, must be obtained from the ordering physician. There may be additional charges for this x-ray, but it is the interest of patient safety and if not performed, the patient my not be permitted to have an MRI.
Is there any preparation for an MRI?
Generally there is no preparation for most MRI procedures. However, if the patient is having an MRI of the Bile Ducts (MRCP), he/she must not eat or drink 6 hours before the exam. We encourage patients to wear clothing without snaps, zippers, buttons or studs. Leave metal objects, such as jewelry, watches and coins at home.
Will I be comfortable during the MRI?
The patient will be made as comfortable as possible for the duration of his/her scan. A cushion is placed under the knees and a blanket is provided for comfort. Please let the requesting physician know if something is needed for pain management or anxiety. They can prescribe some medication prior to the MRI. This medication is not provided by Wentworth Douglass Hospital.
Is the machine loud?
Yes, the machine is very loud. It makes a loud knocking and banging noise. Patients must wear earplugs or headphones to block out the noise and protect his/her hearing. Wentworth-Douglass' MRI offers cinema vision. It is a system that allows patients to view a show or movie on a special virtual reality headset. Patients can bring a DVD or pick one from the hospital's large selection. Also, patients may listen to music, which may be their own selection, or something from the WDH MRI music library.
What if I am claustrophobic?
The technologist will be in contact with the patient continuously during the MRI. They can see, hear and communicate with each patient during the exam. Patient safety, comfort and privacy are of top priority. Many exams (NOT all) can be performed feet first allowing the head to be out of the scanner or not have to go through the machine.
Please tell the ordering physician if there is a chance of claustrophobia or heightened anxiety. The ordering doctor can prescribe some medication to help relax you during the MRI. It is the patient's responsibility to obtain the medications at their local pharmacy and to follow the directions on the label.
Finally, WDH offers a more spacious MRI unit with a "Wide-Bore". This is accomplished via a mobile MRI service that is at the hospital every Wednesday. This machine is wider and shorter and can accommodate larger patients with ease.
When will I get the results?
The radiologists (doctors that read images) at Wentworth-Douglass Hospital will interpret the MRI and dictate a report which is transcribed and send to the ordering physician within 3 business days. The ordering physician should inform the patient of the results. Please call the ordering physician for the test results if it has been longer than 3 business days.