PLEASE NOTE: Gold Coast Spine does not perform these investigations, we are supplying information for your reference only.
What is an MRI?
Magnetic Resonance Imaging (MRI) is an imaging technique that uses magnetic fields, radiofrequencies and a computer to take highly detailed images of the human body. In particular, MRI scans help show soft tissue structures with greater contrast and are therefore better for differentiating the type of tissue that is seen on the scan. MRI does not use radiation, and is generally a simple, pain free procedure.
How do I prepare for my MRI?
Prior to arriving for your MRI scan, you will be asked to complete a series of safety questions to find out if you have any metal or implants in your body. If you should answer YES to any of these questions, it is important that you notify the radiology company as soon as possible. If you are uncertain if you have any of the following devices, please check with your GP or specialist. These questions will include:
In most cases, there is no special preparation for an MRI scan. You can eat and drink normally on the day of the scan and you can continue to take any prescribed medication. It is also important that you bring your referral form and all x-rays, CT scans or ultrasounds taken in the last 2 years that may be relevant to why you are having the scan. The radiologist may like to compare the information or see if your condition has changed since your last scan.
It is very important not to bring any metal into the scan room without letting the radiographer know. Before the scan, you will be asked to remove your wallet, keys, coins, credit cards, bus tickets and mobile phones. Clothing with metal clips will also need to be removed. These can all be damaged by the strong magnet of the MRI scanner, or might cause distortions in the MRI pictures.
How is an MRI scan done?
Flat bed MRI scanners
Most MRI scanners require you to lie on a flat bed that moves into a short tunnel where the pictures are taken. During the scan, you will need to keep very still to improve the quality of the images. The scanner may make a large amount of noise during the scan, which resembles a thumping or humming noise. You will be given earplugs or headphones to assist in blocking out this noise. It is very important that during these periods you keep very still. The time required to complete the scan including getting you ready varies and usually takes between 30 minutes to 1 hour. Trying to remain as relaxed and comfortable during the scan will ensure that the best possible pictures are obtained.
A new upright multi-positional MRI scanner is now available in one location in Australia (Sydney). With an upright MRI scanner there is no tunnel and there is nothing in front of your face so there is no worry about claustrophobia. Also, it can image larger framed individuals, it can assist in diagnosis through the use of weight bearing and multi positional images, and children can be scanned while sitting in their parent’s lap. At this time, there are no upright MRI scanners in Queensland.
What are the risks of an MRI?
There are no known common risks associated the MRI scan itself; there are no radiation exposure risks with MRIs. An allergic reaction to the contrast medium (if used) has been reported, though this is very unlikely. Claustrophobia is also experienced by some patients in flat bed scanners; however, if you have experienced this before or believe this may be a problem make sure you let the staff at Gold Coast Spine know. If you are claustrophobic, you may be referred to one of the recommended local MRI machines that are ‘wide bore’; meaning it has an increased width designed to make the experience more comfortable. If you are very claustrophobic you may also choose to travel to Sydney to have your scan performed in an upright MRI scanner.
Delivery of Results
During your scan, the images will be reviewed for clarity and accuracy by the radiographer. Following your scan, a specialist radiologist will interpret the images; however, this takes some time. A copy of the images obtained from your scan and the radiologist report will be delivered to your referring surgeon. This delivery generally takes several days.
How is a CT scan different to an MRI?
Both a CT and MRI scan provide images of high detail; however, each scan allows the doctor to have different resolutions and images of internal body structures. MRI scans provide better contrast resolution by allowing a differentiation of tissue structures within the body. In contrast, CT scans provide better spatial resolution which allows finer detail to be seen. The images of both scans can be manipulated via a computer to show the tissue in different planes. While neither scan is superior to the other, each scan has its benefits to help assess the disease process and diagnosis depending on the pathology being investigated. In terms of radiation exposure risk, MRI scans do not carry this risk while CT scans do.