Starship Paediatric Radiology
Public Service, Radiology, Paediatrics
Magnetic Resonance Imaging (MRI)
MRI scanners use powerful magnetic forces to produce cross-sectional images and provide different information from that available on CT scanning or ultrasonography. MRI is particularly helpful in diseases of the brain and the spinal cord, as well as in diagnosing infections and tumours of the muscles and bones.
The MRI equipment is similar in structure to CT but the tunnel is much bigger and the space around the patient is slightly less but, due to the special “cameras” MRI utilises, claustrophobia can be a significant issue. The tunnel with the new scanner is 70cm wide and approx. 165cm long.
The strong magnetic forces prevent the use or presence of any metals that are attracted to magnets or equipment that is affected by magnets. Therefore children with certain implants e.g. pacemakers or cochlear implants, are not allowed into the MRI room. You and your child will be thoroughly screened by the technician before being allowed to enter the MRI room.
The MRI unit makes a lot of noise so headphones or earplugs will be used to minimise the noise for your child. In most cases, we can play music or stories while the scan is performed.
The technologists are in a separate room from the scanner itself, but there is a glass window between the rooms and an intercom so that people in the two rooms can speak to each other. Your child will also be provided in most cases with a special mirror which will allow them to see the technician and out of the scanner into the room. A parent or caregiver can usually stay in the scanning room with a child (pending safety checks).
Before a child has imaging with MR, there is a checklist that is filled out by the technologist and parent in order to prevent any problems. These include MRI safety checks, previous surgeries and possible allergies to medicines or foods.
Small children will need general anaesthesia in order to lie still for the time needed for an examination. The scan time will vary depending on the type of examination required, but as a rule it will take around 30-45 minutes. Some may take longer. Please follow all fasting guidelines closely or your child's scan will be cancelled.
A Gadolinium-based contrast agent is used for MRI. It is administered intravenously and circulates through the bloodstream before it is excreted by the kidneys. Its properties allow identification of blood vessels and blood flow to structures in the area being scanned. Your child may require this contrast depending on the imaging question, and this will either be administered by the technologist or a nurse, under radiologist guidance, via a small needle into a vein in the elbow or the back of the hand.
Because there are several MRI centres providing services for paediatric patients, the specific preparation and instructions for the child's study will be sent from each MRI centre. Please read or record all instructions carefully, and note the location of the MRI scanner.
Please try to be on time for your appointments when visiting the MRI Department. We ask people to allow plenty of time to allow for parking and finding the department and also for going over any safety questionnaires and preparation. If, for some reason, your child cannot attend an appointment, please inform the secretary in charge of bookings as soon as possible so that another child can be booked into that time slot. (Reception phone number, Starship Radiology Department is (09) 307 2836. Phone number for Cardiac MRI is (09) 307 2822, extension 24522.)