Magnetic Resonance Imaging
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About MRI
MRI for Kids Brochure - Is MRI safe?
- What is involved with an MRI scan?
- Is MRI painful or uncomfortable?
- Can I be with my child during the MRI scan?
- Are there any special precautions?
- Does my child need to fast?
- Where do I go and how long will it take?
- What if my child is sick or a I am unable to keep the appointment?
- When will I receive the result?
- Mock MRI Scanner
- MRI Images
- MRI Links
About MRI
MRI (Magnetic Resonance Imaging) is one of the latest diagnostic methods for viewing inside the body. MRI is very useful for detecting abnormalities of the brain and spinal cord, blood vessels and other internal organs. During an MRI scan, pictures are taken from different angles and a computer processes these to produce a detailed picture of the body part being scanned.
In children with epilepsy, MRI is used to look for scars, malformations, cysts or tumours which might be causing seizures. Small abnormalities of this type are often not detected with brain CT scans.
In addition to providing pictures of brain structure, some specialised MRI scans provide pictures of the brain chemistry (MR spectroscopy) and brain function (functional MRI).
Is MRI safe?
MRI uses a strong magnetic field and radio waves to obtain the picture. The magnetic field and radio waves are safe and no adverse health effects have been reported with normal use. However, people with certain metal devices in their body cannot be safely scanned with MRI (see below).
There are no X-rays or other similar radiation used in MRI.
What is involved with an MRI scan?
During an MRI scan you simply lie very still on your back while the pictures are being taken. The MRI table that you lie on is narrow and the upper half of your body goes down the tunnel of the machine. The tunnel is well lit and ventilated, you can see what is happening through mirrors, and you can talk to the MRI technologist performing the scan. If you like, you can watch a video on a screen at your feet or listen to a favourite CD or radio station.
Occasionally, an injection of a dye substance is given into a vein to provide extra detail to the pictures. For most children with epilepsy having MRI scans this is not necessary. If an injection is necessary, anaesthetic cream will be put on your hand to make it numb.
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| Quicktime VR scene of the MRI rooms. | |
Is MRI painful or uncomfortable?
There is not a lot of space in the MRI scanner and you need to keep perfectly still to get the best pictures. Foam cushions and Velcro straps are used around your forehead, shoulders and arms to help prevent movement. A special part of the scanner called the head coil, which looks a bit like a cage or a helmet, goes over your head. Finally, the MRI scanner makes loud "knocking" noises so you need to wear special headphones to protect your hearing.
Sample sounds (MP3 files):
Young children, and some older children and adults, find the MRI tunnel and all the restraints frightening and have difficulty keeping still for the 45-60 minutes that it takes to get the best brain pictures. General anaesthesia is usually required for infants and young children (under 7 years), or children who would have difficulty keeping still for that duration.
If you are uncertain about whether your child is having an anaesthetic or not, or you are uncertain whether they will be able to keep still, please contact your doctor or the MRI department.
Can I be with my child during the MRI scan?
One parent may accompany their child during the MRI scan, provided they have no potential MRI risks. If you have other young children with you, you will need to mind them in the waiting area. However, it is prefered that other children are not brought to MRI due to limited space.
If your child requires a general anaesthetic for the procedure, you can only remain with your child until they are asleep. This is so the anaesthetist, nurse and MRI technologist have adequate room to access and monitor your child closely.
If you are pregnant, you may accompany your child into the MRI suite, but you cannot stay with them during the scanning.
Are there any special precautions?
Parents or caregivers are required to complete the Royal Children’s Hospital MRI questionnaire prior to their child’s scan. This is posted to you with the appointment and you are asked to bring the completed questionnaire with you when you come for the scan. The questionnaire asks about your child’s medical history and helps the MRI department ensure you and your child’s safety whilst in the MRI scanning room. If your child has orthodontic braces and is to have a brain scan, you should contact the MRI department to see if this might pose any problems. Clothing with metal zippers and studs cannot be worn in MRI scanner.
The following items are affected by the magnet, and are not permitted into the scanning room for safety reasons: watches, pens, keys, jewellery, hair pins, safety pins, mobile phones, credit cards, pagers, radios and CD players.
Does my child need to fast?
If your child requires sedation or general anaesthesia for the scan, specific instructions about fasting will be given to you by the MRI department. Children are usually fasted for 3-6 hours prior to the anaesthetic, depending on the child’s age, associated medical conditions, and the time of the scan. Antiepileptic medications should be taken with a small amount of clear fluid (1/3 of a cup of water) close to the normal time. If you are uncertain about the specific fasting instructions for your child, please contact the MRI department.
Where do I go and how long will it take?
Most MRI scans for children with epilepsy are done on an outpatient basis. MRI is in the department of Medical Imaging (Radiology) on the 2nd floor of the Royal Children’s Hospital, main building. Signs to Medical Imaging or MRI are present at the Hospital entries, lifts and on the 2nd floor.
Optimal MRI scans for children with epilepsy take about 1 hour. You will be able to leave immediately with your child following the completion of the scan. If your child has had an anaesthetic, he/she will be observed briefly in MRI by the medical and nursing staff prior to leaving. Children under 12 months of age are occasionally admitted to the ward, for brief observation after an MRI with general anaesthetic or sedation.
What if my child is sick or I am unable to keep the appointment?
As you may be aware, there is a waiting list for MRI scans and we do not like to let appointments go wasted. If your child is sick and unlikely to tolerate or cooperate with the scanning, please contact the MRI department as soon as possible. This is particularly important if your child is to have a general anaesthetic.
When will I receive the result?
MRI scans need to be printed from the computer and examined closely by a radiologist. MRI scans have many more pictures with much greater detail than other X-ray or CT scans; thus, they take a lot longer to review and report.
Urgent, inpatient scans are analysed and reported on the same day. Non-urgent, outpatient MRI scans are reported within 2 working days. Reports are sent to the requesting doctor, either by mail or fax. Patients of the Royal Children’s Hospital have their scans kept on file in the Hospital. MRI scans of private patients are usually sent to the requesting doctor with the report.
Please note that the MRI technologist cannot tell you the results of the scan when it is finished and secretarial staff will not give out results over the telephone. You must make arrangements with your doctor for receiving the result.
Mock MRI Scanner
On June 18th 2001, the ‘Mock MRI’ was opened in the Department of Medical Imaging, believed to be the first facility of its kind in the country. The purpose of the Mock MRI is to enable children who require an MRI scan for clinical or research purposes to become familiar with the noisy and confined environment of the scanner and to practise the tasks expected of them. It is hoped that it will reduce the need for general anaesthesia in some young or anxious children requiring anatomical MRI for clinical purposes and assist practitioners obtaining optimal cooperation of children undergoing functional MRI for research or clinical purposes. The Mock MRI is an initiative of the functional MRI research group and was made possible through funds raised by the Brainwave organisation and its donors, most importantly Oakridge Estate and several other Victorian wineries.
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Mock MRI |
The Mock MRI room is located in the Radiology department on the 2nd floor of the main building. The facility has been highlighted in the recently developed brochure ‘MRI for Kids’ which is being distributed with MRI bookings. Parents can request from the MRI booking clerks an opportunity for their child to try out in the Mock MRI if they wish
For more information
If you have questions about the MRI scan, your appointment, anaesthesia etc. please contact the MRI department on (03) 9345 5238.
If you have questions about the need for an MRI scan or general anaesthesia, or questions about the results of the MRI scan, please contact your doctor.
Images
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MRI Links
- Whole Brain Atlas (Harvard)
http://www.med.harvard.edu/AANLIB/home.html
- Brain Imaging Research Institute (Melbourne)
http://www.brain.org.au/